- Email: [email protected]
A New Ferulic Acid–Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance
Journal Pre-proof A New Ferulic Acid-Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance José Venâncio Chaves Júnior, Jonh Anderson Borges dos Santos, Taynara Batista Lins, Rayanne Sales de Araújo Batista, Severino Antônio de Lima Neto, Artur de Santana Oliveira, Fernando Henrique Andrade Nogueira, Ana Paula Barreto Gomes, Damião Pergentino de Sousa, Fábio Santos de Souza, Cícero Flávio Soares Aragão PII:
S0022-3549(19)30807-X
DOI:
https://doi.org/10.1016/j.xphs.2019.12.002
Reference:
XPHS 1818
To appear in:
Journal of Pharmaceutical Sciences
Received Date: 10 September 2019 Revised Date:
22 November 2019
Accepted Date: 3 December 2019
Please cite this article as: Chaves Júnior JV, Borges dos Santos JA, Lins TB, Sales de Araújo Batista R, Antônio de Lima Neto S, de Santana Oliveira A, Andrade Nogueira FH, Barreto Gomes AP, Pergentino de Sousa D, Santos de Souza F, Soares Aragão CF, A New Ferulic Acid-Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance, Journal of Pharmaceutical Sciences (2020), doi: https://doi.org/10.1016/j.xphs.2019.12.002. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Published by Elsevier Inc. on behalf of the American Pharmacists Association.
A New Ferulic Acid-Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance José Venâncio Chaves Júnior¹, Jonh Anderson Borges dos Santos¹, Taynara Batista Lins², Rayanne Sales de Araújo Batista², Severino Antônio de Lima Neto², Artur de Santana Oliveira¹, Fernando Henrique Andrade Nogueira1, Ana Paula Barreto Gomes1, Damião Pergentino de Sousa², Fábio Santos de Souza², Cícero Flávio Soares Aragão¹* ¹Department of Pharmacy, Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Norte, Natal 59010-115, Brazil ²Department of Pharmaceutical Sciences, Federal University of Paraíba, João Pessoa 58051-970, Brazil Abstract Among the various strategies for increasing aqueous solubility of pharmaceutical substances, cocrystals have been emerging as a promising alternative. The ferulic acid (FEA) is a molecule with limited aqueous solubility, but with an interesting pharmacological activity, highlighting its antitumor potential. This study presents the characterization and physicochemical properties of a new cocrystal based on FEA and nicotinamide (NIC). The FEA-NIC cocrystal was obtained by solvent evaporation technique and physicochemically characterized by differential scanning calorimetry (DSC), Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), solid-state nuclear magnetic resonance (ssNMR) and scanning electron microscopy (SEM). The content determination and dissolution profile in different media were analyzed by high performance
liquid
chromatography
(HPLC).
The
results
obtained
with
the
characterization techniques indicated the obtainment of an anhydrous cocrystal of FEA and NIC at a 1:1 molar ratio. The method was reproducible and obtained a high yield, of approximately 99%. Also, a 70% increase in the FEA solubility in the cocrystal and a better dissolution performance than the physical mixture in pH 6.8 were achieved.
Keywords ferulic acid, cocrystal, solubility, dissolution profile
Introduction
Pharmaceutical cocrystals are crystalline structures formed by the interaction of two or more substances through noncovalent bonds in a single crystal lattice, which at least one of them is of pharmacological interest and the other is capable of forming these cocrystals, called coformer.1,2 The crystalline structure of the cocrystal differs from the structure of the individual components, as well as it presents different physicochemical properties.3 The packing of these cocrystals can be understood by the repetition of synthons, supramolecular structures formed by noncovalent bonds of same functional groups, the homosynthons, and of different functional groups, the heterosynthons.4 The most common methods for obtaining the cocrystals are grinding and solution assisted methods.5,6 The methods by grinding consists of milling the components with or without high temperatures and with minimal or no use of solvents, such as hot melt extrusion, liquid-assisted grinding and ball mill.7 Cocrystallization assisted by solution consists in the evaporation of volatile solvents, which can occur more slowly, at room temperature for example,8 or faster, including the rotavaporation and spray drying.9,10 The analytical techniques employed in cocrystals characterization are those capable of studying the characteristics of solids, such as Powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and solid-state nuclear magnetic resonance (ssNMR).5-11 Ferulic acid (FEA), or 4-hydroxy-3-methoxycinnamic acid (Figure 1A), is a phenolic acid derived from cinnamic acid plants being isolated from these sources by enzymatic ways for application in the pharmaceutical and food industry due to its pharmacological properties.12 It is present in plants such as Angelica sinensis, Climinicifuga recemosa and Ligusticum chuangxiong, also found in some fruits such as tomato and orange, and in a higher concentration in cereals such as wheat and maize.13,14 There are several biological activities from this molecule related in the literature regarding its antioxidant potential, anti-inflammatory and anti-diabetic activities.15 One activity to stand out from FEA is its antitumor potential, a synergistic effect with the 5-fluorouracil in cancer cells of the cervix has been reported, and also with the paclitaxel in multidrug resistant cells.16,17
Figure 1. Chemical structures of ferulic acid (A) and nicotinamide (B).
The aqueous solubility is one of the parameters that directly affect the bioavailability of orally administered drugs. There are several strategies employed to improving aqueous solubility, such as particle size reduction, solid dispersions, and inclusion complexes.18 Recently, several studies have shown the increase of the solubility of substances with low aqueous solubility through cocrystals.19,20 Besides the solubility and dissolution, other properties that can be improved with the formation of the cocrystal, such as chemical stability and mechanical properties.21-24 The FEA is a substance with limited aqueous solubility and some techniques like solid dispersion and inclusion complex have already been used to increase its solubility.25-29 One advantage of the cocrystals over the techniques that lead to the amorphization of the material is related to stability, since the crystalline materials do not tend to change phase, as the solid dispersions does.30,31 Some studies have already shown cocrystals with FEA in its composition, acting as a coformer, and without standing out its solubility.32,33 Nicotinamide (NIC), or pyridine-3carboxamide (Figure 1B), is a coformer widely employed in cocrystals aiming to increase drugs aqueous solubility of drugs, since it presents high aqueous solubility that favors the formation of cocrystals with great solvation capacity. Furthermore, NIC is also a low cost product.34-36 A previous study reported a cocrystal hydrate of FEA and NIC, showing the possibility of interaction between these molecules by different crystalline approaches.37 In this context, the objective of this study is to produce a new FEA and NIC cocrystal in order to improve FEA aqueous solubility.
Materials and methods
Materials
Ferulic acid (FEA, 99.5% purity) was purchased from Pharmanostra (Brazil) and nicotinamide (NIC, 99.2% purity) was obtained from Purifarma (Brazil). The solvents used were ethanol (99.9%, Merck) and methanol HPLC grade (99.9%, J. T. Baker).
Preparation of FEA-NIC cocrystal (CC)
The drying methodology was adapted from a previously report.38 Equimolar amounts of FEA and NIC, 1000 mg (5.15 mM) and 628.9 mg (5.15 mM) respectively, were added to a 125 mL round bottom flask and solubilized in 60 mL of ethanol. The flask was then rotoevaporated under reduced pressure at 50 rpm and 60 ºC, with final drying at 50 ºC in a circulating air oven for approximately 30 minutes. Then, the powder was gently scraped off the flask and sifted through a 42 mesh sieve (355 µm). This sample was called CC and was stored in eppendorf at room temperature protected from light.
Control assay: physical mixture (PM)
Equimolar amounts of FEA and NIC powders, previously sieved in 42 mesh (355 µm), were added to a vessel and mixed during 15 minutes in vertical movements, simulating a rotary powder mixer. This sample was prepared to act as a comparison criterion and was denominated physical mixture (PM) and stored at room temperature protected from light.
High performance liquid chromatography (HPLC)
The content and dissolution profile of FEA and NIC were performed according to a previously report,39 on an HPLC system (Prominence, Shimadzu) equipped with a diode array detector (DAD) and a C18 Shim-pack CLC column (250 mm x 4.6 mm; 5 µm). The detection wavelength was set to 268 nm and the sample injection volume was 20 µL. The mobile phase consisted of 20 mM aqueous dibasic sodium phosphate buffer and methanol (70:30, respectively) at an isocratic flow rate of 1.0 mL/min. The linearity was evaluated in triplicate in the concentration range of 5 - 45 µg/mL (FEA) and 3.1 - 28.2 µg/mL (NIC). Validation data are shown in Table S1.
Differential scanning calorimetry (DSC)
The DSC analysis was carried out in a calorimeter (DSC-50 Shimadzu), using 2 mg of the samples in a hermetically sealed aluminum pan. The analysis was performed under a nitrogen atmosphere (flow rate of 50 mL/min), at the temperature range from 25 to 300 ºC, at a heating rate of 10 ºC/min.
Thermogravimetric analysis (TGA)
The thermogravimetric curves were obtained in a thermobalance (TGA-50, Shimadzu). The analysis was performed using 5 mg of the samples in an alumina pan at the temperature range of 25-600 ºC and at a heating hate of 10ºC/min under synthetic air atmosphere (flow rate of 20 mL/min).
Powder X-ray diffraction (PXRD)
The PXRD patterns were obtained in a Bruker D2 Phaser diffractometer with Cu Kα radiation source and a voltage of 30 kV and 30 mA current. Analysis was performed in the 2θ angular region between 5-40º with step size of 0.02º and scan speed of 5º/min.
Fourier transformer infrared spectroscopy (FTIR)
Infrared spectra were obtained in a Perkin Elmer, SPECTRUM 65 model, Fourier transform spectrophotometer coupled to an ATR sampling accessory in the region from 4000 to 550 cm-1 with 20 scans and resolution of 1 cm-1.
Scanning electron microscopy (SEM)
The surface morphology of samples was examined in a Zeiss Leo 1430 VP electron microscope at an accelerating voltage of 10 or 15 kV, in 500 or 1000x magnifications. The samples were coated with gold before analysis.
Solid-state nuclear magnetic resonance (ssNMR) The 13C ssNMR data were acquired on an Bruker Avance III HD NMR Spect. 300 MHz spectrometer (magnetic field strength of 7.0463 T) equipped with a 4 mm CP/MAS probe. Chemical shifts were referred to tetramethylsilane (0 ppm). The spectra were acquired, processed, and analyzed with the software Topspin 3.1 (Bruker). The theoretical spectra were predicted by MestReNova software, version 14.0.1.
Solubility study The solubility assessment methodology was adapted from a previously study.40 In triplicate, the solubility of the samples was evaluated by supersaturation using an orbital shaker (Tecnal model: TE-424) at 37 ºC and 100 rpm. An excess amount of the samples equivalent to 20 mg of FEA were added to a 25 mL erlenmeyer with 10 mL of distilled water pH 6.7. After 24 hours, the samples were filtrated in filter paper, diluted in HPLC mobile phase to 10 µg/mL of FEA and filtered through a 0.22 µm nylon syringe filter.
In vitro dissolution profile
The in vitro dissolution tests were carried out according to the Brazilian Pharmacopeia,41 using a Nova Ética dissolution tester equipped with paddle (method 2) protected from light, in triplicate. The dissolution tests were performed in triplicate in three different media, at pH 1.2 (hydrochloric acid and sodium chloride), pH 4.5 (acetic acid) and pH 6.8 (phosphate buffer). The equivalent of 100 mg of the FEA (162.9 mg for the PM and CC samples) was added to hard capsules. The capsules were attached to a sinker and inserted into each dissolution vessel with 900 mL of medium at 37 ± 0.5 ºC and paddle rotation speed at 50 rpm. Aliquots of 4 mL were collected at predetermined intervals (10, 15, 20, 30, 45 and 60 minutes), immediately filtered through a 0.22 µm syringe filter and diluted to 10 µg/mL in the HPLC mobile phase. The aliquots were not replaced with dissolution medium. The concentration calculations were adjusted according to the remaining media volumes. The dissolution efficiency (DE) was determined using the trapezoidal method, it was calculated from the values of the area under the curve (AUC) of the FEA profiles at different times (t) and total area of rectangle for the respective time (AUCT), expressed as percentage of the area of the rectangle corresponding to 100% dissolution:
=
(0 − )
100%
Reproducibility evaluation
The reproducibility of the cocrystal obtaining method was performed with 3 batches and it was evaluated by process yield and DSC analysis.
Statistical analysis
The comparison of dissolution efficiency results were performed by analysis of variance (ANOVA), followed by Tukey’s post-test. The results were expressed as means (n=3) and statistical significance was set at p < 0.05 (95% confidence interval).
Results and discussion
Differential scanning calorimetry (DSC)
It is well known that cocrystals exhibit different physicochemical properties from their individual components, including their melting points. Therefore, the DSC is a precise technique employed to evaluate the thermal behavior of cocrystals. In most cases, for cocrystals, a single melting point is formed, which is in an intermediate temperature compared to the melting points of the individual components.4,10,32,34,35 The DSC curves of FEA, NIC, PM and CC products are shown in Figure 2. The FEA presented a sharp endothermic peak corresponding to its melting at 175.3 ºC, whereas NIC displayed on sharp peak at 133.4 ºC. In the literature, two polymorphic forms of FEA are described. In the present study, we refers to form I, which has a melting point of approximately 175 ºC.42 The NIC is presented in five polymorphic forms, where form 1 has a sharp peak at a temperature close to 133 ºC.43,44 The PM showed a great anticipation in its melting (115.7 ºC), indicating one physical interaction,45 whereas the CC product had a single intermediate melting peak at temperature close to 139 ºC, compared to its individual components, indicating a product of high purity and the possible formation of a cocrystal.
Figure 2. DSC curves of FEA, NIC, PM and CC products.
Thermogravimetric analysis (TGA)
Although TGA is not employed to determine crystalline structure, this technique allows to identify the presence of solvents in the raw material.35 As in any other raw material, its best application with cocrystals is in the evaluation of its thermal stability.34,38 The thermogravimetric curves of the samples are shown in Figure 3 and detailed thermogravimetric data are summarized in Table S2. The FEA presented two steps of degradation in the range of 290 ºC to 400 ºC and the NIC degraded in one step between 165 ºC and 275 ºC, in accordance with the literature.46,47 The PM and CC products showed similar profiles, with faster degradation than the individual raw materials. However, the mass loss of PM and CC began at temperatures above 157 ºC, which does not compromise its stability. In addition, these results indicate that CC product is not a solvate, as it would be expected a mass loss from ethanol at temperatures around 80 °C. A cocrystal hydrate, synthesized from ferulic acid and nicotinamide monohydrate, showed a 4.5% water loss up to 98 ºC, with degradation starting close to 120 ºC and a melting point of 127 ºC.37 Thus, unlike this cocrystal hydrate, CC is in anhydrous form and has different thermal properties, being more thermally stable because it presented higher melting point and degradation temperature.
Figure 3. TGA curves of FEA, NIC, PM and CC products.
Powder X-ray diffraction (PXRD)
The XRPD is a non-destructive technique widely applied in cocrystal characterization, in which the appearance or disappearance of new peaks in the XRPD patterns, compared to individual components, confirm a change in the crystalline phase and indicate a potential formation of one cocrystal.2,23,24 The XRPD patterns of individual materials and CC products are shown in Figure 4. The FEA presented characteristic peaks at 2θ of 9.0,º 10.5º, 12.7º, 15.5º and 17.3º and NIC at 2θ of 11.4º, 14.9º, 22.3º and 27.4º. These characteristic peaks are according to other reports.25-27,34 The CC exhibited unique diffraction peaks compared to the individual components, at 2θ of 13.8º, 16.3º, 16,6º and 18.9º, whereas characteristic peaks of the individual components were absent at 2θ of 9.0º, 10.5º, 12.7º, 14.9º, 17.3º and 22,2º, suggesting a change in the crystalline phase and the
formation of a cocrystal. Comparing with the isolated raw materials, CC presented lower peak intensity, indicating a less crystalline material, corroborating with the DSC result (lower intensity melting peak). This behavior is observed in other cocrystals already reported, resulting in the change of the crystal structure and related to the particle size reduction.3,24,34,35 No difference between PXRD patterns of individual components and their respective recrystallized materials were observed (Figure S1), discarding polymorphs formation. As expected, the PXRD pattern of PM showed the sum of FEA and NIC peaks (Figure S2). The ferulic acid and nicotinamide cocrystal hydrate,37 also presented a different PXRD pattern than CC, it presented a peak at 2θ of 5º approximately and several other peaks not showed in CC. In the same report,37 there is a PXRD pattern of an anhydrate material from the cocrystal hydrate. However, no other characterization techniques were performed and no details of obtaining were given, presenting peaks not observed in CC, mainly at 2θ of 20-25º. So, clear differences in the structures of cocrystals are noticed when water molecules are present.
Figure 4. PXRD patterns of FEA, NIC and CC. New peaks observed in the cocrystal are signaled with asterisks (*).
Fourier transformer infrared spectroscopy (FTIR)
The FTIR is another technique that is commonly employed in cocrystals characterization that allows us to evaluate their probable formation mechanism. The formation of hydrogen bonds is a highlighted mechanism, represented by the shifting of the bands to regions of lower wavenumbers.3,8,37 The FTIR spectra of individual components and CC are shown in Figure 5 and the respective stretches are summarized in Table 1. The characteristic bands of FEA and NIC were in accordance with the literature.25-27,29,34,48,49 The CC showed bands shifted to lower wavenumbers, indicating the formation of hydrogen bonds. Furthermore, an undefined band occurred at 3513 cm-1, probably involved in the formation of new hydrogen bonds.50 Mainly due to shiftment of N‒H and C=O stretches in CC to lower wavenumbers, is suggested that hydrogen bonds are present in one heterosynthon formation. However, the supramolecular packing cannot be confirmed, since the presence of multiple functional groups on ferulic acid and nicotinamide suggests
various modes of hydrogen bonding between them. No differences were observed for FTIR spectrum of PM in comparison with AFE and NIC spectra (Figure S3).
Figure 5. FTIR spectra of FEA, NIC and CC.
Table 1 FTIR data of FEA, NIC and CC products.
Numerous studies are published with the PXRD, FTIR and DSC characterization techniques suggesting the formation of cocrystals and proposing differences between the cocrystals and other crystalline materials, such as salts and polymorphs.10,21,23,24,35,51 Since FEA and NIC are ionizable molecules and possess a crystalline structure, the formation of salts or polymorphs can’t be ruled out. The “rule of 3” is a well-accepted theory and it states about proton transfer, indicated by the ∆pKa (pKa(base) – pKa(acid)), in which a salt or crystal is expected when ∆pKa > 3 or ∆pKa <0, respectively.5,22,23,35 The pKa of FEA and NIC are 4.6 and 3.4, respectively,52,53 thus the ∆pKa = -1.2, leading us to assume that there was a cocrystal formation.
Solid state Nuclear Magnetic Resonance (ssNMR)
The ssNMR is a non destructive technique that allows to obtain structural information about crystalline solids, for example, in hydrogen bonding, molecular conformation and molecular mobility. Like DSC, FTIR and PXRD, ssNRM is also applied in cocrystals characterization.30,32 A difference in the chemical shift (peak positions) in the ssNMR spectrum of the cocrystal compared to the shifts of their individual components is considered an evidence for the formation of a new phase. As the single crystal x-ray diffraction technique, the ssNMR can also confirm the cocrystal formation, with the advantage to analyze the material in powder form.1,8 Figure 6 presents the
13
C spectrum of the CC product. The Table 2 shows the
chemical shifting attributed for the CC. The spectrum showed FEA and NIC peaks in accordance with the to literature,54,55,56 except the FEA peak at 116.83 ppm, which corroborated to the calculated spectrum. Most peaks were shifted relative to the individual components. In comparison with FEA spectrum obtained from the literature, the major differences observed were for the peak at 172.78 ppm that shifted to 172.14 ppm in the
CC, being this peak related to the carbon of the carboxylic acid of FEA, and for the peak at 56.23 ppm that shifted to 58.31 ppm in the CC, attributed to the carbon of the ether group of the FEA. In comparison with NIC spectrum obtained from the literature, the peak corresponding to the carbon of the amide group shifted from 169.3 ppm to 170.51 ppm in the CC, and also the carbon adjacent to the aromatic nitrogen in the pyridine ring at 149.2 ppm shifted to 148.93 ppm. These results clearly indicate a new phase. The 13C ssNMR is a method which allows to verify the existence of proton transfer, also to differentiate salts from cocrystals. Small changes in peak positions may be considered as a fingerprint for cocrystals, while greater changes indicates a proton transfer. The formation of cocrystals or salts is better visualized when functional groups like carboxylic or nitrogen are present. Its is reported in the literature that a charged assisted hydrogen bond formed by a proton transfer in the carboxylate group is observed when the shiftment is close to 3-7 ppm.2,57 Cocrystals of nicotinamide showed shiftments close to 2 ppm for the carbons of the amide group and for the carbons adjacent to the aromatic nitrogen in the pyridine ring, relative to their individual components.55,56 As observed for CC in Figure 6 and Table 2, the shiftments of the carboxylic carbon of FEA, amide carbon and adjacent pyridine carbon is close to 2 ppm, discarding the proton transfer between carboxylic acid of FEA and NIC, confirming a neutral hydrogen bond. Thus, these evidences indicate the formation of a cocrystal at a 1:1 molar ratio.
Table 2 13
C Chemical shift values attributed for FEA, NIC and CC.
Figure 6. CC ssNMR spectrum.
Scanning electron microscopy (SEM)
As result of change in the crystalline phase, the cocrystal in major cases exhibit differences in particle size and morphology.10,21,24 The morphology of samples surface is shown in Figure 7. The FEA appears mostly as rectangular and needle-shaped particles, whereas NIC exhibits well defined rectangular particles, as observed in the other reports.25,29,58 It is possible to observe in the CC product a homogeneous material, without many traces of FEA and NIC, made of clusters of small particles, indicating a change in its crystalline habit.
Figure 7. SEM images of FEA in 1000x (A), NIC in 500x (B), CC in 1000x (C) and CC in 5000x (D) magnifications.
Solubility and In vitro dissolution
The evaluation of solubility and dissolution profile is important for drugs with limited aqueous solubility, since these aspects plays an important role in the drug rate absorption of orally administered drugs.18 The pure FEA presented a solubility of 0.78 ± 0.06 mg/mL, whereas FEA in PM and CC products exhibit a solubility of 0.96 ± 0.08 mg/mL and 1.33 ± 0.05 mg/mL, which represents an increase of 23% and 70% in FEA solubility, respectively. A representative chromatogram of FEA and NIC in the HPLC quantification is shown in Figure S4. The In vitro dissolution was also improved (Figure 8); an expected result, since dissolution rate also depends on the drug solubility. This improvement can be related to the other reports, since the cocrystals in most cases presents a decrease in the lattice energy of the new crystalline phase, and then a better solvation capacity.1,2,20 In the chosen dissolution media, the pure FEA dissolved partially, and the most evident changes compared to the PM and CC occurred in pH 6.8 (Table S3). The pure FEA reached dissolution of 91% in 60 minutes in pH 6.8, whereas FEA in the CC was completely dissolved in 20 minutes (Figure 8C), showing a better dissolution profile; in addition, the PM showed a lower dissolution rate, similar to the pure FEA. The dissolution efficiency (DE) was used for the dissolution profiles comparison . DE is an approach used to determine which sample has the best dissolution rate.22 Statistical analysis was applied to evaluate the DE of the FEA in different samples at different time intervals (Table 3). According with the analysis described before, at pH 6.8, there is a significant difference in between the samples. The results at 15, 30 and 60 minutes exhibited a variance between FEA in CC and the pure FEA, and the FEA in PM. Despite, at other pH and time intervals no significant differences were observed.
Table 3 Dissolution efficiency (DE) comparison between pure FEA, FEA in PM and FEA in CC at different time intervals.
An interesting observation was seen at pH 1.2, in which a FEA precipitation occurred in the dissolution vessel. This result is unrelated to the cocrystal formation, as this precipitation also occurred with the PM; this suggests a physical or chemical interaction between FEA and NIC. The precipitate refers to FEA because the NIC dissolved 100% (Figure S5). This finding indicates that, in future formulation studies, gastric protection for CC would be required.
Figure 8. Dissolution profiles of pure FEA, FEA in PM and FEA in CC products at pH 1.2 (A), 4.5 (B) and 6.8 (C).
Content determination and reproducibility evaluation
The contents of FEA and NIC in PM and CC products are summarized in Table 4. In both samples, the content of the substances was close to 100% with low RSD values, confirming the 1:1 molar ratio and homogeneity of the material.
Table 4 FEA and NIC content in the PM and CC samples.
It was possible to perceive an excellent reproducibility in the obtainment the cocrystals (Fig. 9), with differences of ± 1 ºC in the melting point and average ∆Hfusion of 104 J g-1 (Table 5). Additionally, an excellent powder yield of 98.3 ± 1.3% was obtained.
Figure 9. DSC curves of three different CC batches.
Table 5 DSC data for three batches of the CC product.
Conclusion
This study has demonstrated that it was possible to improve the solubility and dissolution performance of FEA, a molecule with a great pharmacological potential and limited aqueous solubility, through a new crystalline solid strategy. The results obtained with the characterization techniques indicated the formation of a cocrystal of FEA and
NIC, at a 1:1 molar ratio, through a fast obtaining process which showed high reproducibility, providing powders with good homogeneity. The dissolution performance of FEA in the CC was superior to isolated FEA at pH 6.8. Considering that the increase of FEA aqueous solubility plays an important role to obtain a better bioavailability, the cocrystal formed with NIC appears as a promising alternative for this purpose.
Acknowledgement
We thank Coordination of Improvement of Higher Level Personnel (CAPES), código for funding this work.
References 1. 2. 3.
4. 5.
6. 7.
8.
9. 10. 11.
12.
13.
Bolla G, Nangia A. Pharmaceutical cocrystals: walking the talk. Chem Commun. 2016;52(54):8342‒8360. Cerreia Vioglio P, Chierotti MR, Gobetto R. Pharmaceutical aspects of salt and cocrystal forms of APIs and characterization challenges. Adv Drug Deliver Rev. 2017;117:86‒110. Ranjan S, Devarapalli R, Kundu S, Vengala VR, Ghosh A, Reddy CM. Three new hydrochlorothiazide cocrystals: structural analyses and solubility studies. J Mol Struct. 2017;1133:405‒410. Allu S, Bolla G, Tothadi S, Nangia A. Supramolecular synthons in bumetanide cocrystals and ternary products. Cryst Growth Des. 2017;17(8):4225‒4236. Karimi-Jafari M, Padrela L, Walker GM, Croker DM. Creating cocrystals: a review of pharmaceutical cocrystal preparation routes and applications. Cryst Growth Des. 2018;18(10):63706387. Malamatari M, Ross SA, Douroumis D, Velaga SP. Experimental cocrystal screening and solution based scale-up cocrystallization methods. Adv Drug Deliver Rev. 2017;117:162‒177. Ross SA, Lamprou DA, Douroumis D. Engineering and manufacturing of pharmaceutical cocrystals: a review on solvent-free manufacturing technologies. Chem Commun. 2016;52(57):8772‒8786. Bruni G, Maggi L, Mustarelli P, Sakaj M, Friuli V, Ferrara C, Berbenni V, Girella A, Milanese C, Marini, A. Enhancing the pharmaceutical behavior of nateglinide by cocrystallization: physicochemical assessment of cocrystal formation and informed use of differential scanning calorimetry for its quantitative characterization. J Pharm Sci. 2019;108(4):1529‒1539. Pagire SK, Jadav N, Vangala VR, Whiteside B, Paradkar A. Thermodynamic investigation of carbamazepine-saccharin co-crystal polymorphs. J Pharm Sci. 2017;106(8):2009‒2014. Patil SP, Modi SR, Bansal AK. Generation of 1:1 carbamazepine:nicotinamide cocrystal by spray drying. Eur J Pharm Sci. 2014;62:251‒257. Lin HL, Zhang GC, Lin SY. Real-time co-crystal screening and formation between indomethacin and saccharin via DSC analytical technique or DSC–FTIR microspectroscopy. J Therm Anal Calor. 2015;120:679‒687. Wu H, Li H, Xue Y, Luo G, Gan L, Liu J, Mao L, Long M. High efficiency co-production of ferulic acid and xylooligosaccharides from wheat bran by recombinant xylanase and feruloyl esterase. Biochem Eng J. 2017;120:41‒48. Mancuso C, Santangelo R. Ferulic acid: pharmacological and toxicological aspects, Food Chem Toxicol. 2014;65:185‒195.
14. Paiva L, Goldbeck R, Santos WD, Squina FM. Ferulic acid and derivatives: molecules with potential application in the pharmaceutical field. Braz J Pharm Sci. 2013;49(3):395‒411. 15. Silva EO, Batista R. Ferulic acid and naturally occurring compounds bearing a feruloyl moiety: a review on their structures, occurrence, and potential health benefits. Comp Rev Food Sci Food Saf. 2017;16(4):580‒616. 16. Hemaiswarya S, Doble M. Combination of phenylpropanoids with 5-fluorouracil as anti-cancer agentes against human cervical cancer (HeLa) cell line. Phytomedicine. 2013;20(2):151‒158. 17. Muthusamy G, Balupillai A, Ramasamy K, Shanmugam M, Gunaseelan S, Mary B, Prasad NR. Ferulic acid reverses ABCB1-mediated paclitaxel resistance in MDR cell lines. Eur J Pharmacol. 2016;786:194‒203. 18. Khadka P, Ro J, Kim H, Kim I, Kim JT, Kim H, Cho JM, Yun G, Lee J. Pharmaceutical particle technologies: an approach to improve drug solubility, dissolution and bioavailability. Asian J Pharm Sci. 2014;9(6):304‒316. 19. Kuminek G, Cao F, Rocha ABO, Cardoso SG, Rodríguez-Hornedo N. Cocrystals to facilitate delivery of poorly soluble compounds beyond-rule-of-5. Adv Drug Deliv Rev. 2016;101:143‒166. 20. Wang N, Xie C, Lu H, Guo N, Lou Y, Su W, Hao H. Cocrystal and its application in the field of active pharmaceutical ingredients and food ingredients. Curr Pharma Des. 2018;24(21):2339‒2348. 21. Deng JH, Lu TB, Sun CC, Chen JM. Dapagliflozin-citric acid cocrystal showing better solid state properties than dapagliflozin. Eur J Pharm Sci. 2017;104:255‒261. 22. Thipparaboina R, Kumar D, Mittapalli S, Balasubramanian S, Nangia A, Shastri NR. Ionic, neutral and hybrid acid-base crystalline adducts of lamotrigine with improved pharmaceutical performance. Cryst Growth Des. 2015;15(12):5816‒5828. 23. Silva Filho SF, Pereira AC, Sarraguça JMG, Sarraguça MC, Lopes J, Façanha Filho PF, Santos AO, Silva Ribeiro PR. Synthesis of a glibenclamide cocrystal: full spectroscopic and termal characterization. J Pharm Sci. 2018;107(6):1597‒1604. 24. Hiendrawan S, Veriansyah B, Widjojokusumo E, Soewandhi SN, Wikarsa S, Tjandrawinata RR. Physicochemical and mechanical properties of paracetamol cocrystal with 5-nitroisophthalic acid. Int J Pharm. 2016;497(1-2):106‒113. 25. Wang J, Cao Y, Sun B, Wang C. Characterization of inclusion complex of trans-ferulic acid and hydroxypropyl-β-cyclodextrin. Food Chem. 2011;124(3):1069‒1075. 26. Yu DD, Yang JM, Branford-White C, Lu P, Zhang L, Zhu LM. Third generation solid dispersions of ferulic acid in electrospun composite nanofibers. Int J Pharm. 2010;400(1-2):158‒164. 27. Nadal JM, Gomes ML, Borsato DM, Almeida MA, Barboza FM, Zawadzki SF, Farago PV, Zanin SM. Spray-dried solid dispersions containing ferulic acid: comparative analysis of three carriers, in vitro dissolution, antioxidant potential and in vivo anti-platete effect. Drug Dev Ind Pharm. 2016;42(11):1813‒1824. 28. Panwar R, Raghuwanshi N, Srivastava AK, Pruthi V. In-vivo sustained release of nanoencapsulated ferulic acid and its impact in induced diabetes. Mater Sci Eng C. 2018;92:381‒392. 29. Li L, Liu Y, Xue Y, Zhu J, Wang X, Dong Y. Preparation of a ferulic acid-phospholipid complex to improve solubility, dissolution, and B16F10 cellular melanogenesis inhibition activity. Chem Cent. 2017;11(26). 30. Shaikh R, Singh R, Walker GM, Croker DM. Pharmaceutical cocrystal drug products: an outlook on product development. Trends Pharmacol Sci. 2018;39(12):1033‒1048. 31. Haser A, Zhang F. New strategies for improving the development and performance of amorphous sold dispersions. AAPS PharmSciTec. 2018;19(3):978‒990. 32. Swapna B, Maddileti D, Nangia A. Cocrystals of the tuberculosis drug isoniazid: polymorphism, isostructurality, and stability. Cryst Growth Des. 2014;14(11):5991‒6005. 33. Sarmah KK, Boro K, Arhangelskis M, Thakuria R. Crystal structure landscape of ethenzamide: a physicochemical property study. CrystEngComm. 2017;19(5):826‒833. 34. Müllers KC, Paisana M, Wahl MA. Simultaneous formation and micronization of pharmaceutical cocrystals by rapid expansion of supercritical solutions (RESS). Pharm Res. 2015;32(7):702‒713. 35. Huang Y, Zhang B, Gao Y, Zhang J, Shi L. Baicalein-nicotinamide cocrystal with enhanced solubility, dissolution, and oral bioavailability. J Pharm Sci. 2013;103(8):2330‒2337. 36. Zhang SW, Brunskill APJ, Schwartz E, Sun S. Celecoxib−nicotinamide cocrystal revisited: can entropy control cocrystal formation?. Cryst Growth Des. 2017;17(5):2836‒2843.
37. Clarke HD, Arora KK, Bass H, Kavuru P, Ong TT, Pujari T, Wojtas L, Zaworotko MJ. Structurestability relationships in cocrystal hydrates: does the promiscuity of water make crystalline hydrates the nemesis of crystal engineering?. Cryst Growth Des. 2010;10(5):2152‒2167. 38. Zhou Z, Li W, Sun WJ, Lu R, Tong HHY, Sun CC, Zheng Y. Resveratrol cocrystals with enhanced solubility and tabletability. Int J Pharm. 2016;509(1-2):391-399. 39. Chaves Júnior JV, Dos Santos JAB, Ferreira GLR, Porto DL, Oliveira AS, Nogueira FHA, Souza FS, Aragão CFS. Validation of HPLC and UHPLC methods for the simultaneous quantification of ferulic acid and nicotinamide in the presence of their degradation products. Anal Methods. 2019;11(36):4644‒4650. 40. Putra OD, Umeda D, Nugraha YP, Furuishi T, Nagase H, Fukuzawa K, Uekusa H, Yonemochi E. Solubility improvement of epalrestat by layered strucuture formation via cocrystallization. CrystEngComm. 2017;19(19):2614‒2622. 41. FB. 2010. Farmacopeia Brasileira 2010. 5 ed., Brasil: Agência Nacional de Vigilância Sanitária. Anvisa. 42. Taek Sohn Y, Hee Oh J. Characterization of physicochemical properties of ferulic acid. Arch Pharm Res. 2003;26(12):1002‒1008. 43. Hino T, Ford JL, Powell MW. Assessment of nicotinamide polymorphs by differential scanning calorimetry. Thermo Acta. 2001;374:85‒92. 44. Li J, Bourne SA, Caira MR. New polymorphs of isonicotinamide and nicotinamide. Chem Commun. 2011;47(5):1530‒1532. 45. Lima IPB, Lima NGPB, Barros DMC, Oliveira TS, Barbosa EG, Gomes APB, Ferrari M, Nascimento TG, Aragão CFS. Compatibility study of tretinoin with several pharmaceutical excipients by thermal and non-thermal techniques. J Therm Anal Calor. 2015;120(1):733‒747. 46. Bezerra GSN, Pereira MAV, Ostrosky EA, Barbosa EG, Moura MGV, Ferrari M, Aragão CFS, Gomes APB. Compatibility study between ferulic acid and excipients used in cosmetic formulations by TG/DTG, DSC and FTIR. J Therm Anal Calor. 2017;127(2):1683‒1681. 47. Moreschi ECP, Matos JR, Almeida-Muradian L. Thermal analysis of vitamin PP and niacinamide. J Therm Anal Calor. 2009;98:161‒164. 48. Kalinowska M, Piekut J, Bruss A, Follet C, Sienkiewicz-Gromiuk J, Świsłocka R, Rzączyńska Z, Lewandowski W. Spectroscopic (FT-IR, FT-Raman, 1H, 13C NMR, UV/VIS), thermogravimetric and antimicrobial studies of Ca(II), Mn(II), Cu(II), Zn(II) and Cd(II) complexes of ferulic acid. Spectrochim Acta A Mol Biomol Spectrosc. 2014;122:631‒638. 49. Ramalingam S, Periandy S, Govindarajan M, Mohan S. FT-IR and FT-Raman vibrational spectra and molecular structure investigation of nicotinamide: a combined experimental and theoretical study. Spectrochim Acta A Mol Biomol Spectrosc. 2010;75(5):1552‒1558. 50. Shimono K, Kadota K, Tozuka Y, Shimosaka A, Shirakawa Y, Hidaka J. Kinetics of co-crystal formation with caffeine and citric acid via liquid-assisted grinding analyzed using the distinct element method. Eur J Pharm Sci. 2015;76:217‒224. 51. Shayanfar A, Jouyban A. Physicochemical characterization of a new cocrystal of ketoconazole. Powder Technol. 2014;262:242‒248. 52. Dupoiron S, Lameloise ML, Pommet M, Bennaceur O, Lewandowski R, Allais F, Teixeira ARS, Rémond C, Rakotoarivonina H. A novel and integrative process: from enzymatic fractionation of wheat bran with a hemicellulasic cocktail to the recovery of ferulic acid by weak anion exchange skin. Indust Crops Prod. 2017;105:148‒155. 53. Schiewe J, Mrestani Y, Neubert R. Application and optimization of capillary zone electrophoresis in vitamin analysis. J Chromatogr A. 1995;717(1-2):255‒259. 54. Almeida RR, Silva Damasceno ET, de Carvalho SYB, de Carvalho GSG, Gontijo LAP, de Lima Guimarães LG. Chitosan nanogels condensed to ferulic acid for the essential oil of Lippia origanoides Kunth encapsulation. Carbohydr Polym. 2018;(188):268‒275. 55. Li P, Chu Y, Wang L, Menslow-Jr RM, Yu K, Zhang H, Deng Z. Structure determination of the theophylline-nicotinamide cocrystal: a combined powder XRD, 1D solid-state NMR, and theoretical calculation study. CrystEngComm. 2014;16(15):3141‒3147. 56. Vasisht K, Chadha K, Karan M, Bhalla Y, Jena AK, Chadha R. Enhancing biopharmaceutical parameters of bioflavonoid quercetin by cocrystallization. CrystEngComm. 2016;18(8): 1403‒1415. 57. Martins ICB, Sardo M, Alig E, Fink L, Schmidt MU, Mafra L, Duarte MT. Enhancing Adamantylamine solubility through salt formation: novel products studied by x-ray diffraction and solid-state NMR. Cryst Growth Des. 2019;(19):1860‒1873.
58. Shikhar A, Bommana MM, Gupta SS, Squillante E. Formulation development of carbamazepinenicotinamide co-crystals complexed with γ-cyclodextrin using supercritical fluid process. J Supercrit Fluids. 2011;55(3):1070‒1078.
Figure S1. PXRD patterns of recrystallized FEA and NIC.
Figure S2. PXRD pattern of PM.
Figure S3. FTIR spectrum of PM.
Figure S4. FEA and NIC chromatogram obtained by HPLC.
Figure S5. NIC dissolution profiles in PM and CC at pH 1.2 (a), 4.5 (b) and 6.8 (c).
Table S1 Chromatographic data for FEA and NIC from HPLC.
Table S2 Thermogravimetric data of FEA, NIC, PM and CC products.
Table S3 Dissolution of pure FEA and FEA in PM and CC samples.
Table 1 FTIR data of FEA, NIC and CC products. Peak assignment
AFE (cm-1)
CC (cm-1)
NIC (cm-1)
ν (OH)
3430
3432
--
ν (C=O)
1687, 1661
1675
1674
ν (C-O-C)
1276
1263
--
ν (NH2)
--
3320, 3195
3353, 3144
ν (CN)
--
1390
1393
δ (NH2)
--
--
1615
ν (C=C)
1618, 1597, 1512, 1431
1629, 1591, 1591, 1515
1574, 1485
ν= Stretching, δ= Deformation
Table 2 13
C Chemical shift values in ppm attributed for FEA, NIC and CC. FEA1
FEAcalc
CCexp
NIC2
NICcalc
CCexp
C1
125.60
126.72
125.47
C11
149.2
149.87
148.93
C2
113.95
111.73
113.93
C12
122.9
124.80
125.47
C3
147.94
149.00
148.93
C13
137.9
136.90
134.09
C4
147.94
149.42
148.93
C14
129.3
129.40
125.47
C5
111.69
116.15
115.02
C15
152.0
150.10
151.99
C6
125.60
123.90
123.29
C16
169.3
170.75
170.51
C7
144.77
145.77
144.74
C8
108.55
117.27
116.83
C9
172.78
169.19
172.14
C10
56.23
56.25
58.31
The number of each carbon is presented in Fig. 6. 1= (Almeida et al., 2018); 2= (Li et al., 2014); calc=theoretical; exp= experimental.
Table 3 Dissolution efficiency (DE) comparison between pure FEA, FEA in PM and FEA in CC at different time intervals. pH 1.2 Time (min) 20
a,b
30
a,b,c
60a,b
FEA 53.73
pH 4.5
FEA PM
FEA CC
16.14
15.53
Time (min) 20
b
FEA 61.10
pH 6.8 FEA PM 59.18
FEA CC 55.92
Time (min)
FEA
FEA PM
FEA CC
20
a,b,c
54.56
28.72
63.57
a,b,c
65.67
45.70
76.14
77.60
70.70
89.21
62.80
22.93
28.93
30
69.75
68.93
68.90
30
75.07
39.53
34.88
60
80.59
81.58
83.19
60a,b,c
a
b
c
Data expressed in % as mean (n= 3); p < 0.05 for FEA vs FEA PM; p < 0.05 for FEA vs FEA CC; p < 0.05 for FEA PM vs FEA CC.
Table 4 FEA and NIC content in the PM and CC products. Content (% ± RSD) PM
CC
FEA
102.4 ± 1.20
100.80 ± 2.79
NIC
101.10 ± 1.49
100.08 ± 2.83
Table 5 DSC data for three batches of the CC product. Tonset (ºC)
Tpeak (ºC)
Tendset (ºC)
∆Hfusion (J g-1)
Batch 1
135.8
138.8
143.0
105.6
Batch 2
137.0
139.5
142.4
109.1
Batch 3
136.7
139.1
143.5
98.4
CC
• • • •
Ferulic acid-nicotinamide cocrystals were produced by solvent evaporation process The cocrystal was formed at a 1:1 molar ratio in the anhydrous form Pure ferulic acid showed lower aqueous solubility and dissolution rate than the cocrystal The pH influenced in the dissolution profiles
S0022-3549(19)30807-X
DOI:
https://doi.org/10.1016/j.xphs.2019.12.002
Reference:
XPHS 1818
To appear in:
Journal of Pharmaceutical Sciences
Received Date: 10 September 2019 Revised Date:
22 November 2019
Accepted Date: 3 December 2019
Please cite this article as: Chaves Júnior JV, Borges dos Santos JA, Lins TB, Sales de Araújo Batista R, Antônio de Lima Neto S, de Santana Oliveira A, Andrade Nogueira FH, Barreto Gomes AP, Pergentino de Sousa D, Santos de Souza F, Soares Aragão CF, A New Ferulic Acid-Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance, Journal of Pharmaceutical Sciences (2020), doi: https://doi.org/10.1016/j.xphs.2019.12.002. This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. © 2019 Published by Elsevier Inc. on behalf of the American Pharmacists Association.
A New Ferulic Acid-Nicotinamide Cocrystal With Improved Solubility and Dissolution Performance José Venâncio Chaves Júnior¹, Jonh Anderson Borges dos Santos¹, Taynara Batista Lins², Rayanne Sales de Araújo Batista², Severino Antônio de Lima Neto², Artur de Santana Oliveira¹, Fernando Henrique Andrade Nogueira1, Ana Paula Barreto Gomes1, Damião Pergentino de Sousa², Fábio Santos de Souza², Cícero Flávio Soares Aragão¹* ¹Department of Pharmacy, Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Norte, Natal 59010-115, Brazil ²Department of Pharmaceutical Sciences, Federal University of Paraíba, João Pessoa 58051-970, Brazil Abstract Among the various strategies for increasing aqueous solubility of pharmaceutical substances, cocrystals have been emerging as a promising alternative. The ferulic acid (FEA) is a molecule with limited aqueous solubility, but with an interesting pharmacological activity, highlighting its antitumor potential. This study presents the characterization and physicochemical properties of a new cocrystal based on FEA and nicotinamide (NIC). The FEA-NIC cocrystal was obtained by solvent evaporation technique and physicochemically characterized by differential scanning calorimetry (DSC), Powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), solid-state nuclear magnetic resonance (ssNMR) and scanning electron microscopy (SEM). The content determination and dissolution profile in different media were analyzed by high performance
liquid
chromatography
(HPLC).
The
results
obtained
with
the
characterization techniques indicated the obtainment of an anhydrous cocrystal of FEA and NIC at a 1:1 molar ratio. The method was reproducible and obtained a high yield, of approximately 99%. Also, a 70% increase in the FEA solubility in the cocrystal and a better dissolution performance than the physical mixture in pH 6.8 were achieved.
Keywords ferulic acid, cocrystal, solubility, dissolution profile
Introduction
Pharmaceutical cocrystals are crystalline structures formed by the interaction of two or more substances through noncovalent bonds in a single crystal lattice, which at least one of them is of pharmacological interest and the other is capable of forming these cocrystals, called coformer.1,2 The crystalline structure of the cocrystal differs from the structure of the individual components, as well as it presents different physicochemical properties.3 The packing of these cocrystals can be understood by the repetition of synthons, supramolecular structures formed by noncovalent bonds of same functional groups, the homosynthons, and of different functional groups, the heterosynthons.4 The most common methods for obtaining the cocrystals are grinding and solution assisted methods.5,6 The methods by grinding consists of milling the components with or without high temperatures and with minimal or no use of solvents, such as hot melt extrusion, liquid-assisted grinding and ball mill.7 Cocrystallization assisted by solution consists in the evaporation of volatile solvents, which can occur more slowly, at room temperature for example,8 or faster, including the rotavaporation and spray drying.9,10 The analytical techniques employed in cocrystals characterization are those capable of studying the characteristics of solids, such as Powder X-ray diffraction (PXRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and solid-state nuclear magnetic resonance (ssNMR).5-11 Ferulic acid (FEA), or 4-hydroxy-3-methoxycinnamic acid (Figure 1A), is a phenolic acid derived from cinnamic acid plants being isolated from these sources by enzymatic ways for application in the pharmaceutical and food industry due to its pharmacological properties.12 It is present in plants such as Angelica sinensis, Climinicifuga recemosa and Ligusticum chuangxiong, also found in some fruits such as tomato and orange, and in a higher concentration in cereals such as wheat and maize.13,14 There are several biological activities from this molecule related in the literature regarding its antioxidant potential, anti-inflammatory and anti-diabetic activities.15 One activity to stand out from FEA is its antitumor potential, a synergistic effect with the 5-fluorouracil in cancer cells of the cervix has been reported, and also with the paclitaxel in multidrug resistant cells.16,17
Figure 1. Chemical structures of ferulic acid (A) and nicotinamide (B).
The aqueous solubility is one of the parameters that directly affect the bioavailability of orally administered drugs. There are several strategies employed to improving aqueous solubility, such as particle size reduction, solid dispersions, and inclusion complexes.18 Recently, several studies have shown the increase of the solubility of substances with low aqueous solubility through cocrystals.19,20 Besides the solubility and dissolution, other properties that can be improved with the formation of the cocrystal, such as chemical stability and mechanical properties.21-24 The FEA is a substance with limited aqueous solubility and some techniques like solid dispersion and inclusion complex have already been used to increase its solubility.25-29 One advantage of the cocrystals over the techniques that lead to the amorphization of the material is related to stability, since the crystalline materials do not tend to change phase, as the solid dispersions does.30,31 Some studies have already shown cocrystals with FEA in its composition, acting as a coformer, and without standing out its solubility.32,33 Nicotinamide (NIC), or pyridine-3carboxamide (Figure 1B), is a coformer widely employed in cocrystals aiming to increase drugs aqueous solubility of drugs, since it presents high aqueous solubility that favors the formation of cocrystals with great solvation capacity. Furthermore, NIC is also a low cost product.34-36 A previous study reported a cocrystal hydrate of FEA and NIC, showing the possibility of interaction between these molecules by different crystalline approaches.37 In this context, the objective of this study is to produce a new FEA and NIC cocrystal in order to improve FEA aqueous solubility.
Materials and methods
Materials
Ferulic acid (FEA, 99.5% purity) was purchased from Pharmanostra (Brazil) and nicotinamide (NIC, 99.2% purity) was obtained from Purifarma (Brazil). The solvents used were ethanol (99.9%, Merck) and methanol HPLC grade (99.9%, J. T. Baker).
Preparation of FEA-NIC cocrystal (CC)
The drying methodology was adapted from a previously report.38 Equimolar amounts of FEA and NIC, 1000 mg (5.15 mM) and 628.9 mg (5.15 mM) respectively, were added to a 125 mL round bottom flask and solubilized in 60 mL of ethanol. The flask was then rotoevaporated under reduced pressure at 50 rpm and 60 ºC, with final drying at 50 ºC in a circulating air oven for approximately 30 minutes. Then, the powder was gently scraped off the flask and sifted through a 42 mesh sieve (355 µm). This sample was called CC and was stored in eppendorf at room temperature protected from light.
Control assay: physical mixture (PM)
Equimolar amounts of FEA and NIC powders, previously sieved in 42 mesh (355 µm), were added to a vessel and mixed during 15 minutes in vertical movements, simulating a rotary powder mixer. This sample was prepared to act as a comparison criterion and was denominated physical mixture (PM) and stored at room temperature protected from light.
High performance liquid chromatography (HPLC)
The content and dissolution profile of FEA and NIC were performed according to a previously report,39 on an HPLC system (Prominence, Shimadzu) equipped with a diode array detector (DAD) and a C18 Shim-pack CLC column (250 mm x 4.6 mm; 5 µm). The detection wavelength was set to 268 nm and the sample injection volume was 20 µL. The mobile phase consisted of 20 mM aqueous dibasic sodium phosphate buffer and methanol (70:30, respectively) at an isocratic flow rate of 1.0 mL/min. The linearity was evaluated in triplicate in the concentration range of 5 - 45 µg/mL (FEA) and 3.1 - 28.2 µg/mL (NIC). Validation data are shown in Table S1.
Differential scanning calorimetry (DSC)
The DSC analysis was carried out in a calorimeter (DSC-50 Shimadzu), using 2 mg of the samples in a hermetically sealed aluminum pan. The analysis was performed under a nitrogen atmosphere (flow rate of 50 mL/min), at the temperature range from 25 to 300 ºC, at a heating rate of 10 ºC/min.
Thermogravimetric analysis (TGA)
The thermogravimetric curves were obtained in a thermobalance (TGA-50, Shimadzu). The analysis was performed using 5 mg of the samples in an alumina pan at the temperature range of 25-600 ºC and at a heating hate of 10ºC/min under synthetic air atmosphere (flow rate of 20 mL/min).
Powder X-ray diffraction (PXRD)
The PXRD patterns were obtained in a Bruker D2 Phaser diffractometer with Cu Kα radiation source and a voltage of 30 kV and 30 mA current. Analysis was performed in the 2θ angular region between 5-40º with step size of 0.02º and scan speed of 5º/min.
Fourier transformer infrared spectroscopy (FTIR)
Infrared spectra were obtained in a Perkin Elmer, SPECTRUM 65 model, Fourier transform spectrophotometer coupled to an ATR sampling accessory in the region from 4000 to 550 cm-1 with 20 scans and resolution of 1 cm-1.
Scanning electron microscopy (SEM)
The surface morphology of samples was examined in a Zeiss Leo 1430 VP electron microscope at an accelerating voltage of 10 or 15 kV, in 500 or 1000x magnifications. The samples were coated with gold before analysis.
Solid-state nuclear magnetic resonance (ssNMR) The 13C ssNMR data were acquired on an Bruker Avance III HD NMR Spect. 300 MHz spectrometer (magnetic field strength of 7.0463 T) equipped with a 4 mm CP/MAS probe. Chemical shifts were referred to tetramethylsilane (0 ppm). The spectra were acquired, processed, and analyzed with the software Topspin 3.1 (Bruker). The theoretical spectra were predicted by MestReNova software, version 14.0.1.
Solubility study The solubility assessment methodology was adapted from a previously study.40 In triplicate, the solubility of the samples was evaluated by supersaturation using an orbital shaker (Tecnal model: TE-424) at 37 ºC and 100 rpm. An excess amount of the samples equivalent to 20 mg of FEA were added to a 25 mL erlenmeyer with 10 mL of distilled water pH 6.7. After 24 hours, the samples were filtrated in filter paper, diluted in HPLC mobile phase to 10 µg/mL of FEA and filtered through a 0.22 µm nylon syringe filter.
In vitro dissolution profile
The in vitro dissolution tests were carried out according to the Brazilian Pharmacopeia,41 using a Nova Ética dissolution tester equipped with paddle (method 2) protected from light, in triplicate. The dissolution tests were performed in triplicate in three different media, at pH 1.2 (hydrochloric acid and sodium chloride), pH 4.5 (acetic acid) and pH 6.8 (phosphate buffer). The equivalent of 100 mg of the FEA (162.9 mg for the PM and CC samples) was added to hard capsules. The capsules were attached to a sinker and inserted into each dissolution vessel with 900 mL of medium at 37 ± 0.5 ºC and paddle rotation speed at 50 rpm. Aliquots of 4 mL were collected at predetermined intervals (10, 15, 20, 30, 45 and 60 minutes), immediately filtered through a 0.22 µm syringe filter and diluted to 10 µg/mL in the HPLC mobile phase. The aliquots were not replaced with dissolution medium. The concentration calculations were adjusted according to the remaining media volumes. The dissolution efficiency (DE) was determined using the trapezoidal method, it was calculated from the values of the area under the curve (AUC) of the FEA profiles at different times (t) and total area of rectangle for the respective time (AUCT), expressed as percentage of the area of the rectangle corresponding to 100% dissolution:
=
(0 − )
100%
Reproducibility evaluation
The reproducibility of the cocrystal obtaining method was performed with 3 batches and it was evaluated by process yield and DSC analysis.
Statistical analysis
The comparison of dissolution efficiency results were performed by analysis of variance (ANOVA), followed by Tukey’s post-test. The results were expressed as means (n=3) and statistical significance was set at p < 0.05 (95% confidence interval).
Results and discussion
Differential scanning calorimetry (DSC)
It is well known that cocrystals exhibit different physicochemical properties from their individual components, including their melting points. Therefore, the DSC is a precise technique employed to evaluate the thermal behavior of cocrystals. In most cases, for cocrystals, a single melting point is formed, which is in an intermediate temperature compared to the melting points of the individual components.4,10,32,34,35 The DSC curves of FEA, NIC, PM and CC products are shown in Figure 2. The FEA presented a sharp endothermic peak corresponding to its melting at 175.3 ºC, whereas NIC displayed on sharp peak at 133.4 ºC. In the literature, two polymorphic forms of FEA are described. In the present study, we refers to form I, which has a melting point of approximately 175 ºC.42 The NIC is presented in five polymorphic forms, where form 1 has a sharp peak at a temperature close to 133 ºC.43,44 The PM showed a great anticipation in its melting (115.7 ºC), indicating one physical interaction,45 whereas the CC product had a single intermediate melting peak at temperature close to 139 ºC, compared to its individual components, indicating a product of high purity and the possible formation of a cocrystal.
Figure 2. DSC curves of FEA, NIC, PM and CC products.
Thermogravimetric analysis (TGA)
Although TGA is not employed to determine crystalline structure, this technique allows to identify the presence of solvents in the raw material.35 As in any other raw material, its best application with cocrystals is in the evaluation of its thermal stability.34,38 The thermogravimetric curves of the samples are shown in Figure 3 and detailed thermogravimetric data are summarized in Table S2. The FEA presented two steps of degradation in the range of 290 ºC to 400 ºC and the NIC degraded in one step between 165 ºC and 275 ºC, in accordance with the literature.46,47 The PM and CC products showed similar profiles, with faster degradation than the individual raw materials. However, the mass loss of PM and CC began at temperatures above 157 ºC, which does not compromise its stability. In addition, these results indicate that CC product is not a solvate, as it would be expected a mass loss from ethanol at temperatures around 80 °C. A cocrystal hydrate, synthesized from ferulic acid and nicotinamide monohydrate, showed a 4.5% water loss up to 98 ºC, with degradation starting close to 120 ºC and a melting point of 127 ºC.37 Thus, unlike this cocrystal hydrate, CC is in anhydrous form and has different thermal properties, being more thermally stable because it presented higher melting point and degradation temperature.
Figure 3. TGA curves of FEA, NIC, PM and CC products.
Powder X-ray diffraction (PXRD)
The XRPD is a non-destructive technique widely applied in cocrystal characterization, in which the appearance or disappearance of new peaks in the XRPD patterns, compared to individual components, confirm a change in the crystalline phase and indicate a potential formation of one cocrystal.2,23,24 The XRPD patterns of individual materials and CC products are shown in Figure 4. The FEA presented characteristic peaks at 2θ of 9.0,º 10.5º, 12.7º, 15.5º and 17.3º and NIC at 2θ of 11.4º, 14.9º, 22.3º and 27.4º. These characteristic peaks are according to other reports.25-27,34 The CC exhibited unique diffraction peaks compared to the individual components, at 2θ of 13.8º, 16.3º, 16,6º and 18.9º, whereas characteristic peaks of the individual components were absent at 2θ of 9.0º, 10.5º, 12.7º, 14.9º, 17.3º and 22,2º, suggesting a change in the crystalline phase and the
formation of a cocrystal. Comparing with the isolated raw materials, CC presented lower peak intensity, indicating a less crystalline material, corroborating with the DSC result (lower intensity melting peak). This behavior is observed in other cocrystals already reported, resulting in the change of the crystal structure and related to the particle size reduction.3,24,34,35 No difference between PXRD patterns of individual components and their respective recrystallized materials were observed (Figure S1), discarding polymorphs formation. As expected, the PXRD pattern of PM showed the sum of FEA and NIC peaks (Figure S2). The ferulic acid and nicotinamide cocrystal hydrate,37 also presented a different PXRD pattern than CC, it presented a peak at 2θ of 5º approximately and several other peaks not showed in CC. In the same report,37 there is a PXRD pattern of an anhydrate material from the cocrystal hydrate. However, no other characterization techniques were performed and no details of obtaining were given, presenting peaks not observed in CC, mainly at 2θ of 20-25º. So, clear differences in the structures of cocrystals are noticed when water molecules are present.
Figure 4. PXRD patterns of FEA, NIC and CC. New peaks observed in the cocrystal are signaled with asterisks (*).
Fourier transformer infrared spectroscopy (FTIR)
The FTIR is another technique that is commonly employed in cocrystals characterization that allows us to evaluate their probable formation mechanism. The formation of hydrogen bonds is a highlighted mechanism, represented by the shifting of the bands to regions of lower wavenumbers.3,8,37 The FTIR spectra of individual components and CC are shown in Figure 5 and the respective stretches are summarized in Table 1. The characteristic bands of FEA and NIC were in accordance with the literature.25-27,29,34,48,49 The CC showed bands shifted to lower wavenumbers, indicating the formation of hydrogen bonds. Furthermore, an undefined band occurred at 3513 cm-1, probably involved in the formation of new hydrogen bonds.50 Mainly due to shiftment of N‒H and C=O stretches in CC to lower wavenumbers, is suggested that hydrogen bonds are present in one heterosynthon formation. However, the supramolecular packing cannot be confirmed, since the presence of multiple functional groups on ferulic acid and nicotinamide suggests
various modes of hydrogen bonding between them. No differences were observed for FTIR spectrum of PM in comparison with AFE and NIC spectra (Figure S3).
Figure 5. FTIR spectra of FEA, NIC and CC.
Table 1 FTIR data of FEA, NIC and CC products.
Numerous studies are published with the PXRD, FTIR and DSC characterization techniques suggesting the formation of cocrystals and proposing differences between the cocrystals and other crystalline materials, such as salts and polymorphs.10,21,23,24,35,51 Since FEA and NIC are ionizable molecules and possess a crystalline structure, the formation of salts or polymorphs can’t be ruled out. The “rule of 3” is a well-accepted theory and it states about proton transfer, indicated by the ∆pKa (pKa(base) – pKa(acid)), in which a salt or crystal is expected when ∆pKa > 3 or ∆pKa <0, respectively.5,22,23,35 The pKa of FEA and NIC are 4.6 and 3.4, respectively,52,53 thus the ∆pKa = -1.2, leading us to assume that there was a cocrystal formation.
Solid state Nuclear Magnetic Resonance (ssNMR)
The ssNMR is a non destructive technique that allows to obtain structural information about crystalline solids, for example, in hydrogen bonding, molecular conformation and molecular mobility. Like DSC, FTIR and PXRD, ssNRM is also applied in cocrystals characterization.30,32 A difference in the chemical shift (peak positions) in the ssNMR spectrum of the cocrystal compared to the shifts of their individual components is considered an evidence for the formation of a new phase. As the single crystal x-ray diffraction technique, the ssNMR can also confirm the cocrystal formation, with the advantage to analyze the material in powder form.1,8 Figure 6 presents the
13
C spectrum of the CC product. The Table 2 shows the
chemical shifting attributed for the CC. The spectrum showed FEA and NIC peaks in accordance with the to literature,54,55,56 except the FEA peak at 116.83 ppm, which corroborated to the calculated spectrum. Most peaks were shifted relative to the individual components. In comparison with FEA spectrum obtained from the literature, the major differences observed were for the peak at 172.78 ppm that shifted to 172.14 ppm in the
CC, being this peak related to the carbon of the carboxylic acid of FEA, and for the peak at 56.23 ppm that shifted to 58.31 ppm in the CC, attributed to the carbon of the ether group of the FEA. In comparison with NIC spectrum obtained from the literature, the peak corresponding to the carbon of the amide group shifted from 169.3 ppm to 170.51 ppm in the CC, and also the carbon adjacent to the aromatic nitrogen in the pyridine ring at 149.2 ppm shifted to 148.93 ppm. These results clearly indicate a new phase. The 13C ssNMR is a method which allows to verify the existence of proton transfer, also to differentiate salts from cocrystals. Small changes in peak positions may be considered as a fingerprint for cocrystals, while greater changes indicates a proton transfer. The formation of cocrystals or salts is better visualized when functional groups like carboxylic or nitrogen are present. Its is reported in the literature that a charged assisted hydrogen bond formed by a proton transfer in the carboxylate group is observed when the shiftment is close to 3-7 ppm.2,57 Cocrystals of nicotinamide showed shiftments close to 2 ppm for the carbons of the amide group and for the carbons adjacent to the aromatic nitrogen in the pyridine ring, relative to their individual components.55,56 As observed for CC in Figure 6 and Table 2, the shiftments of the carboxylic carbon of FEA, amide carbon and adjacent pyridine carbon is close to 2 ppm, discarding the proton transfer between carboxylic acid of FEA and NIC, confirming a neutral hydrogen bond. Thus, these evidences indicate the formation of a cocrystal at a 1:1 molar ratio.
Table 2 13
C Chemical shift values attributed for FEA, NIC and CC.
Figure 6. CC ssNMR spectrum.
Scanning electron microscopy (SEM)
As result of change in the crystalline phase, the cocrystal in major cases exhibit differences in particle size and morphology.10,21,24 The morphology of samples surface is shown in Figure 7. The FEA appears mostly as rectangular and needle-shaped particles, whereas NIC exhibits well defined rectangular particles, as observed in the other reports.25,29,58 It is possible to observe in the CC product a homogeneous material, without many traces of FEA and NIC, made of clusters of small particles, indicating a change in its crystalline habit.
Figure 7. SEM images of FEA in 1000x (A), NIC in 500x (B), CC in 1000x (C) and CC in 5000x (D) magnifications.
Solubility and In vitro dissolution
The evaluation of solubility and dissolution profile is important for drugs with limited aqueous solubility, since these aspects plays an important role in the drug rate absorption of orally administered drugs.18 The pure FEA presented a solubility of 0.78 ± 0.06 mg/mL, whereas FEA in PM and CC products exhibit a solubility of 0.96 ± 0.08 mg/mL and 1.33 ± 0.05 mg/mL, which represents an increase of 23% and 70% in FEA solubility, respectively. A representative chromatogram of FEA and NIC in the HPLC quantification is shown in Figure S4. The In vitro dissolution was also improved (Figure 8); an expected result, since dissolution rate also depends on the drug solubility. This improvement can be related to the other reports, since the cocrystals in most cases presents a decrease in the lattice energy of the new crystalline phase, and then a better solvation capacity.1,2,20 In the chosen dissolution media, the pure FEA dissolved partially, and the most evident changes compared to the PM and CC occurred in pH 6.8 (Table S3). The pure FEA reached dissolution of 91% in 60 minutes in pH 6.8, whereas FEA in the CC was completely dissolved in 20 minutes (Figure 8C), showing a better dissolution profile; in addition, the PM showed a lower dissolution rate, similar to the pure FEA. The dissolution efficiency (DE) was used for the dissolution profiles comparison . DE is an approach used to determine which sample has the best dissolution rate.22 Statistical analysis was applied to evaluate the DE of the FEA in different samples at different time intervals (Table 3). According with the analysis described before, at pH 6.8, there is a significant difference in between the samples. The results at 15, 30 and 60 minutes exhibited a variance between FEA in CC and the pure FEA, and the FEA in PM. Despite, at other pH and time intervals no significant differences were observed.
Table 3 Dissolution efficiency (DE) comparison between pure FEA, FEA in PM and FEA in CC at different time intervals.
An interesting observation was seen at pH 1.2, in which a FEA precipitation occurred in the dissolution vessel. This result is unrelated to the cocrystal formation, as this precipitation also occurred with the PM; this suggests a physical or chemical interaction between FEA and NIC. The precipitate refers to FEA because the NIC dissolved 100% (Figure S5). This finding indicates that, in future formulation studies, gastric protection for CC would be required.
Figure 8. Dissolution profiles of pure FEA, FEA in PM and FEA in CC products at pH 1.2 (A), 4.5 (B) and 6.8 (C).
Content determination and reproducibility evaluation
The contents of FEA and NIC in PM and CC products are summarized in Table 4. In both samples, the content of the substances was close to 100% with low RSD values, confirming the 1:1 molar ratio and homogeneity of the material.
Table 4 FEA and NIC content in the PM and CC samples.
It was possible to perceive an excellent reproducibility in the obtainment the cocrystals (Fig. 9), with differences of ± 1 ºC in the melting point and average ∆Hfusion of 104 J g-1 (Table 5). Additionally, an excellent powder yield of 98.3 ± 1.3% was obtained.
Figure 9. DSC curves of three different CC batches.
Table 5 DSC data for three batches of the CC product.
Conclusion
This study has demonstrated that it was possible to improve the solubility and dissolution performance of FEA, a molecule with a great pharmacological potential and limited aqueous solubility, through a new crystalline solid strategy. The results obtained with the characterization techniques indicated the formation of a cocrystal of FEA and
NIC, at a 1:1 molar ratio, through a fast obtaining process which showed high reproducibility, providing powders with good homogeneity. The dissolution performance of FEA in the CC was superior to isolated FEA at pH 6.8. Considering that the increase of FEA aqueous solubility plays an important role to obtain a better bioavailability, the cocrystal formed with NIC appears as a promising alternative for this purpose.
Acknowledgement
We thank Coordination of Improvement of Higher Level Personnel (CAPES), código for funding this work.
References 1. 2. 3.
4. 5.
6. 7.
8.
9. 10. 11.
12.
13.
Bolla G, Nangia A. Pharmaceutical cocrystals: walking the talk. Chem Commun. 2016;52(54):8342‒8360. Cerreia Vioglio P, Chierotti MR, Gobetto R. Pharmaceutical aspects of salt and cocrystal forms of APIs and characterization challenges. Adv Drug Deliver Rev. 2017;117:86‒110. Ranjan S, Devarapalli R, Kundu S, Vengala VR, Ghosh A, Reddy CM. Three new hydrochlorothiazide cocrystals: structural analyses and solubility studies. J Mol Struct. 2017;1133:405‒410. Allu S, Bolla G, Tothadi S, Nangia A. Supramolecular synthons in bumetanide cocrystals and ternary products. Cryst Growth Des. 2017;17(8):4225‒4236. Karimi-Jafari M, Padrela L, Walker GM, Croker DM. Creating cocrystals: a review of pharmaceutical cocrystal preparation routes and applications. Cryst Growth Des. 2018;18(10):63706387. Malamatari M, Ross SA, Douroumis D, Velaga SP. Experimental cocrystal screening and solution based scale-up cocrystallization methods. Adv Drug Deliver Rev. 2017;117:162‒177. Ross SA, Lamprou DA, Douroumis D. Engineering and manufacturing of pharmaceutical cocrystals: a review on solvent-free manufacturing technologies. Chem Commun. 2016;52(57):8772‒8786. Bruni G, Maggi L, Mustarelli P, Sakaj M, Friuli V, Ferrara C, Berbenni V, Girella A, Milanese C, Marini, A. Enhancing the pharmaceutical behavior of nateglinide by cocrystallization: physicochemical assessment of cocrystal formation and informed use of differential scanning calorimetry for its quantitative characterization. J Pharm Sci. 2019;108(4):1529‒1539. Pagire SK, Jadav N, Vangala VR, Whiteside B, Paradkar A. Thermodynamic investigation of carbamazepine-saccharin co-crystal polymorphs. J Pharm Sci. 2017;106(8):2009‒2014. Patil SP, Modi SR, Bansal AK. Generation of 1:1 carbamazepine:nicotinamide cocrystal by spray drying. Eur J Pharm Sci. 2014;62:251‒257. Lin HL, Zhang GC, Lin SY. Real-time co-crystal screening and formation between indomethacin and saccharin via DSC analytical technique or DSC–FTIR microspectroscopy. J Therm Anal Calor. 2015;120:679‒687. Wu H, Li H, Xue Y, Luo G, Gan L, Liu J, Mao L, Long M. High efficiency co-production of ferulic acid and xylooligosaccharides from wheat bran by recombinant xylanase and feruloyl esterase. Biochem Eng J. 2017;120:41‒48. Mancuso C, Santangelo R. Ferulic acid: pharmacological and toxicological aspects, Food Chem Toxicol. 2014;65:185‒195.
14. Paiva L, Goldbeck R, Santos WD, Squina FM. Ferulic acid and derivatives: molecules with potential application in the pharmaceutical field. Braz J Pharm Sci. 2013;49(3):395‒411. 15. Silva EO, Batista R. Ferulic acid and naturally occurring compounds bearing a feruloyl moiety: a review on their structures, occurrence, and potential health benefits. Comp Rev Food Sci Food Saf. 2017;16(4):580‒616. 16. Hemaiswarya S, Doble M. Combination of phenylpropanoids with 5-fluorouracil as anti-cancer agentes against human cervical cancer (HeLa) cell line. Phytomedicine. 2013;20(2):151‒158. 17. Muthusamy G, Balupillai A, Ramasamy K, Shanmugam M, Gunaseelan S, Mary B, Prasad NR. Ferulic acid reverses ABCB1-mediated paclitaxel resistance in MDR cell lines. Eur J Pharmacol. 2016;786:194‒203. 18. Khadka P, Ro J, Kim H, Kim I, Kim JT, Kim H, Cho JM, Yun G, Lee J. Pharmaceutical particle technologies: an approach to improve drug solubility, dissolution and bioavailability. Asian J Pharm Sci. 2014;9(6):304‒316. 19. Kuminek G, Cao F, Rocha ABO, Cardoso SG, Rodríguez-Hornedo N. Cocrystals to facilitate delivery of poorly soluble compounds beyond-rule-of-5. Adv Drug Deliv Rev. 2016;101:143‒166. 20. Wang N, Xie C, Lu H, Guo N, Lou Y, Su W, Hao H. Cocrystal and its application in the field of active pharmaceutical ingredients and food ingredients. Curr Pharma Des. 2018;24(21):2339‒2348. 21. Deng JH, Lu TB, Sun CC, Chen JM. Dapagliflozin-citric acid cocrystal showing better solid state properties than dapagliflozin. Eur J Pharm Sci. 2017;104:255‒261. 22. Thipparaboina R, Kumar D, Mittapalli S, Balasubramanian S, Nangia A, Shastri NR. Ionic, neutral and hybrid acid-base crystalline adducts of lamotrigine with improved pharmaceutical performance. Cryst Growth Des. 2015;15(12):5816‒5828. 23. Silva Filho SF, Pereira AC, Sarraguça JMG, Sarraguça MC, Lopes J, Façanha Filho PF, Santos AO, Silva Ribeiro PR. Synthesis of a glibenclamide cocrystal: full spectroscopic and termal characterization. J Pharm Sci. 2018;107(6):1597‒1604. 24. Hiendrawan S, Veriansyah B, Widjojokusumo E, Soewandhi SN, Wikarsa S, Tjandrawinata RR. Physicochemical and mechanical properties of paracetamol cocrystal with 5-nitroisophthalic acid. Int J Pharm. 2016;497(1-2):106‒113. 25. Wang J, Cao Y, Sun B, Wang C. Characterization of inclusion complex of trans-ferulic acid and hydroxypropyl-β-cyclodextrin. Food Chem. 2011;124(3):1069‒1075. 26. Yu DD, Yang JM, Branford-White C, Lu P, Zhang L, Zhu LM. Third generation solid dispersions of ferulic acid in electrospun composite nanofibers. Int J Pharm. 2010;400(1-2):158‒164. 27. Nadal JM, Gomes ML, Borsato DM, Almeida MA, Barboza FM, Zawadzki SF, Farago PV, Zanin SM. Spray-dried solid dispersions containing ferulic acid: comparative analysis of three carriers, in vitro dissolution, antioxidant potential and in vivo anti-platete effect. Drug Dev Ind Pharm. 2016;42(11):1813‒1824. 28. Panwar R, Raghuwanshi N, Srivastava AK, Pruthi V. In-vivo sustained release of nanoencapsulated ferulic acid and its impact in induced diabetes. Mater Sci Eng C. 2018;92:381‒392. 29. Li L, Liu Y, Xue Y, Zhu J, Wang X, Dong Y. Preparation of a ferulic acid-phospholipid complex to improve solubility, dissolution, and B16F10 cellular melanogenesis inhibition activity. Chem Cent. 2017;11(26). 30. Shaikh R, Singh R, Walker GM, Croker DM. Pharmaceutical cocrystal drug products: an outlook on product development. Trends Pharmacol Sci. 2018;39(12):1033‒1048. 31. Haser A, Zhang F. New strategies for improving the development and performance of amorphous sold dispersions. AAPS PharmSciTec. 2018;19(3):978‒990. 32. Swapna B, Maddileti D, Nangia A. Cocrystals of the tuberculosis drug isoniazid: polymorphism, isostructurality, and stability. Cryst Growth Des. 2014;14(11):5991‒6005. 33. Sarmah KK, Boro K, Arhangelskis M, Thakuria R. Crystal structure landscape of ethenzamide: a physicochemical property study. CrystEngComm. 2017;19(5):826‒833. 34. Müllers KC, Paisana M, Wahl MA. Simultaneous formation and micronization of pharmaceutical cocrystals by rapid expansion of supercritical solutions (RESS). Pharm Res. 2015;32(7):702‒713. 35. Huang Y, Zhang B, Gao Y, Zhang J, Shi L. Baicalein-nicotinamide cocrystal with enhanced solubility, dissolution, and oral bioavailability. J Pharm Sci. 2013;103(8):2330‒2337. 36. Zhang SW, Brunskill APJ, Schwartz E, Sun S. Celecoxib−nicotinamide cocrystal revisited: can entropy control cocrystal formation?. Cryst Growth Des. 2017;17(5):2836‒2843.
37. Clarke HD, Arora KK, Bass H, Kavuru P, Ong TT, Pujari T, Wojtas L, Zaworotko MJ. Structurestability relationships in cocrystal hydrates: does the promiscuity of water make crystalline hydrates the nemesis of crystal engineering?. Cryst Growth Des. 2010;10(5):2152‒2167. 38. Zhou Z, Li W, Sun WJ, Lu R, Tong HHY, Sun CC, Zheng Y. Resveratrol cocrystals with enhanced solubility and tabletability. Int J Pharm. 2016;509(1-2):391-399. 39. Chaves Júnior JV, Dos Santos JAB, Ferreira GLR, Porto DL, Oliveira AS, Nogueira FHA, Souza FS, Aragão CFS. Validation of HPLC and UHPLC methods for the simultaneous quantification of ferulic acid and nicotinamide in the presence of their degradation products. Anal Methods. 2019;11(36):4644‒4650. 40. Putra OD, Umeda D, Nugraha YP, Furuishi T, Nagase H, Fukuzawa K, Uekusa H, Yonemochi E. Solubility improvement of epalrestat by layered strucuture formation via cocrystallization. CrystEngComm. 2017;19(19):2614‒2622. 41. FB. 2010. Farmacopeia Brasileira 2010. 5 ed., Brasil: Agência Nacional de Vigilância Sanitária. Anvisa. 42. Taek Sohn Y, Hee Oh J. Characterization of physicochemical properties of ferulic acid. Arch Pharm Res. 2003;26(12):1002‒1008. 43. Hino T, Ford JL, Powell MW. Assessment of nicotinamide polymorphs by differential scanning calorimetry. Thermo Acta. 2001;374:85‒92. 44. Li J, Bourne SA, Caira MR. New polymorphs of isonicotinamide and nicotinamide. Chem Commun. 2011;47(5):1530‒1532. 45. Lima IPB, Lima NGPB, Barros DMC, Oliveira TS, Barbosa EG, Gomes APB, Ferrari M, Nascimento TG, Aragão CFS. Compatibility study of tretinoin with several pharmaceutical excipients by thermal and non-thermal techniques. J Therm Anal Calor. 2015;120(1):733‒747. 46. Bezerra GSN, Pereira MAV, Ostrosky EA, Barbosa EG, Moura MGV, Ferrari M, Aragão CFS, Gomes APB. Compatibility study between ferulic acid and excipients used in cosmetic formulations by TG/DTG, DSC and FTIR. J Therm Anal Calor. 2017;127(2):1683‒1681. 47. Moreschi ECP, Matos JR, Almeida-Muradian L. Thermal analysis of vitamin PP and niacinamide. J Therm Anal Calor. 2009;98:161‒164. 48. Kalinowska M, Piekut J, Bruss A, Follet C, Sienkiewicz-Gromiuk J, Świsłocka R, Rzączyńska Z, Lewandowski W. Spectroscopic (FT-IR, FT-Raman, 1H, 13C NMR, UV/VIS), thermogravimetric and antimicrobial studies of Ca(II), Mn(II), Cu(II), Zn(II) and Cd(II) complexes of ferulic acid. Spectrochim Acta A Mol Biomol Spectrosc. 2014;122:631‒638. 49. Ramalingam S, Periandy S, Govindarajan M, Mohan S. FT-IR and FT-Raman vibrational spectra and molecular structure investigation of nicotinamide: a combined experimental and theoretical study. Spectrochim Acta A Mol Biomol Spectrosc. 2010;75(5):1552‒1558. 50. Shimono K, Kadota K, Tozuka Y, Shimosaka A, Shirakawa Y, Hidaka J. Kinetics of co-crystal formation with caffeine and citric acid via liquid-assisted grinding analyzed using the distinct element method. Eur J Pharm Sci. 2015;76:217‒224. 51. Shayanfar A, Jouyban A. Physicochemical characterization of a new cocrystal of ketoconazole. Powder Technol. 2014;262:242‒248. 52. Dupoiron S, Lameloise ML, Pommet M, Bennaceur O, Lewandowski R, Allais F, Teixeira ARS, Rémond C, Rakotoarivonina H. A novel and integrative process: from enzymatic fractionation of wheat bran with a hemicellulasic cocktail to the recovery of ferulic acid by weak anion exchange skin. Indust Crops Prod. 2017;105:148‒155. 53. Schiewe J, Mrestani Y, Neubert R. Application and optimization of capillary zone electrophoresis in vitamin analysis. J Chromatogr A. 1995;717(1-2):255‒259. 54. Almeida RR, Silva Damasceno ET, de Carvalho SYB, de Carvalho GSG, Gontijo LAP, de Lima Guimarães LG. Chitosan nanogels condensed to ferulic acid for the essential oil of Lippia origanoides Kunth encapsulation. Carbohydr Polym. 2018;(188):268‒275. 55. Li P, Chu Y, Wang L, Menslow-Jr RM, Yu K, Zhang H, Deng Z. Structure determination of the theophylline-nicotinamide cocrystal: a combined powder XRD, 1D solid-state NMR, and theoretical calculation study. CrystEngComm. 2014;16(15):3141‒3147. 56. Vasisht K, Chadha K, Karan M, Bhalla Y, Jena AK, Chadha R. Enhancing biopharmaceutical parameters of bioflavonoid quercetin by cocrystallization. CrystEngComm. 2016;18(8): 1403‒1415. 57. Martins ICB, Sardo M, Alig E, Fink L, Schmidt MU, Mafra L, Duarte MT. Enhancing Adamantylamine solubility through salt formation: novel products studied by x-ray diffraction and solid-state NMR. Cryst Growth Des. 2019;(19):1860‒1873.
58. Shikhar A, Bommana MM, Gupta SS, Squillante E. Formulation development of carbamazepinenicotinamide co-crystals complexed with γ-cyclodextrin using supercritical fluid process. J Supercrit Fluids. 2011;55(3):1070‒1078.
Figure S1. PXRD patterns of recrystallized FEA and NIC.
Figure S2. PXRD pattern of PM.
Figure S3. FTIR spectrum of PM.
Figure S4. FEA and NIC chromatogram obtained by HPLC.
Figure S5. NIC dissolution profiles in PM and CC at pH 1.2 (a), 4.5 (b) and 6.8 (c).
Table S1 Chromatographic data for FEA and NIC from HPLC.
Table S2 Thermogravimetric data of FEA, NIC, PM and CC products.
Table S3 Dissolution of pure FEA and FEA in PM and CC samples.
Table 1 FTIR data of FEA, NIC and CC products. Peak assignment
AFE (cm-1)
CC (cm-1)
NIC (cm-1)
ν (OH)
3430
3432
--
ν (C=O)
1687, 1661
1675
1674
ν (C-O-C)
1276
1263
--
ν (NH2)
--
3320, 3195
3353, 3144
ν (CN)
--
1390
1393
δ (NH2)
--
--
1615
ν (C=C)
1618, 1597, 1512, 1431
1629, 1591, 1591, 1515
1574, 1485
ν= Stretching, δ= Deformation
Table 2 13
C Chemical shift values in ppm attributed for FEA, NIC and CC. FEA1
FEAcalc
CCexp
NIC2
NICcalc
CCexp
C1
125.60
126.72
125.47
C11
149.2
149.87
148.93
C2
113.95
111.73
113.93
C12
122.9
124.80
125.47
C3
147.94
149.00
148.93
C13
137.9
136.90
134.09
C4
147.94
149.42
148.93
C14
129.3
129.40
125.47
C5
111.69
116.15
115.02
C15
152.0
150.10
151.99
C6
125.60
123.90
123.29
C16
169.3
170.75
170.51
C7
144.77
145.77
144.74
C8
108.55
117.27
116.83
C9
172.78
169.19
172.14
C10
56.23
56.25
58.31
The number of each carbon is presented in Fig. 6. 1= (Almeida et al., 2018); 2= (Li et al., 2014); calc=theoretical; exp= experimental.
Table 3 Dissolution efficiency (DE) comparison between pure FEA, FEA in PM and FEA in CC at different time intervals. pH 1.2 Time (min) 20
a,b
30
a,b,c
60a,b
FEA 53.73
pH 4.5
FEA PM
FEA CC
16.14
15.53
Time (min) 20
b
FEA 61.10
pH 6.8 FEA PM 59.18
FEA CC 55.92
Time (min)
FEA
FEA PM
FEA CC
20
a,b,c
54.56
28.72
63.57
a,b,c
65.67
45.70
76.14
77.60
70.70
89.21
62.80
22.93
28.93
30
69.75
68.93
68.90
30
75.07
39.53
34.88
60
80.59
81.58
83.19
60a,b,c
a
b
c
Data expressed in % as mean (n= 3); p < 0.05 for FEA vs FEA PM; p < 0.05 for FEA vs FEA CC; p < 0.05 for FEA PM vs FEA CC.
Table 4 FEA and NIC content in the PM and CC products. Content (% ± RSD) PM
CC
FEA
102.4 ± 1.20
100.80 ± 2.79
NIC
101.10 ± 1.49
100.08 ± 2.83
Table 5 DSC data for three batches of the CC product. Tonset (ºC)
Tpeak (ºC)
Tendset (ºC)
∆Hfusion (J g-1)
Batch 1
135.8
138.8
143.0
105.6
Batch 2
137.0
139.5
142.4
109.1
Batch 3
136.7
139.1
143.5
98.4
CC
• • • •
Ferulic acid-nicotinamide cocrystals were produced by solvent evaporation process The cocrystal was formed at a 1:1 molar ratio in the anhydrous form Pure ferulic acid showed lower aqueous solubility and dissolution rate than the cocrystal The pH influenced in the dissolution profiles