Molecularly imprinted polymer based sensor for measuring of zileuton: Evaluation as a modifier for carbon paste electrode in electrochemically recognition

Accepted Manuscript Title: Molecularly Imprinted Polymer based Sensor for Measuring of Zileuton: Evaluation as a Modifier for Carbon Paste Electrode in Electrochemically Recognition Authors: Mohammad Reza Baezzat, Maryam Bagheri, Elaheh Abdollahi PII: DOI: Reference:

S2352-4928(18)30410-0 https://doi.org/10.1016/j.mtcomm.2018.12.013 MTCOMM 474

To appear in: Received date: Accepted date:

30 September 2018 18 December 2018

Please cite this article as: Baezzat MR, Bagheri M, Abdollahi E, Molecularly Imprinted Polymer based Sensor for Measuring of Zileuton: Evaluation as a Modifier for Carbon Paste Electrode in Electrochemically Recognition, Materials Today Communications (2018), https://doi.org/10.1016/j.mtcomm.2018.12.013 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. 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.

Molecularly Imprinted Polymer based Sensor for Measuring of Zileuton: Evaluation as a Modifier for Carbon Paste Electrode in Electrochemically Recognition Mohammad Reza Baezzat*a, Maryam Bagheria, Elaheh Abdollahi*a,b a

Department of Chemistry, Payam Noor University, Tehran, Iran. Department of Chemistry, Amikabir University of Technology, Tehran, Iran.

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Abstract: For the first time, a modified carbon paste electrode by using molecularly imprinted polymer (MIP) was designed and prepared as a high performance selective sensor for Zileuton determination. The MIP was synthetized by noncovalent mechanism via bulk polymerization in presence of Zileuton as template molecule. The Polymer backbone was based on methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA). The Polymers was chemically characterized by Fourier Transform Infrared spectroscopy (FTIR) analysis. Morphology of MIP particles was studied by Scanning Electron Microscopy (SEM) technique. Then the MIP and non-imprinted polymer (NIP) as blank one were used to modify bare carbon paste electrode. The modified electrodes were evaluated to study electrochemical behavior of Zileuton by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Some factors such as pH of electrolyte and scan rate were optimized for current response of modified carbon paste electrode. Electrochemical response for Zileuton on the bare carbon paste electrode and modified electrodes were compared together. The designed methodology resulted the wide concentration linear range with the correlation coefficient of R2 ≥ 0.9920, limit of detection (LOD) = 0.189 µg mL-1 and RSD ≤ 2.65, suitable molecular recognition and high selectivity for Zileuton compared to the studied structurally similar compounds. The modified sensor, also presented high ability for Zileuton determination in spiked human plasma (11.8 µg mL-1) with recovery of 99.96%.

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Keywords: Molecularly Imprinted Polymers, Cyclic Voltammetry, Molecular Recognition, Zileuton. 1. Introduction Zileuton (Zyflo; N-(1-benzo[b]thien- 2-ylethyl)-N-hydroxyurea) is the only approved inhibitor of 5-lipoxygenase and is thought to intervene with allergic and inflammatory diseases by suppression of leukotriene biosynthesis [1]. Zileuton is 93% bound to plasma proteins, primarily to albumin, with minor binding to alpha-1-acid glycoprotein [2]. The drug contains a single chiral center (Fig. 1), is administered as a racemic mixture of (R)-(+)and (S)-(-)-enantiomers, and is characterized by a plasma half-life of about 4 h [3,4].

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Different techniques have used for determination of Zileuton amount, such as electrochemical methods including cyclic voltammetry and differential pulse voltammetry [5,6], polarography [7], spectroscopy methods such as UV [8-11], chromatography [12-15]. However, these techniques are mostly very expensive and long time is required for some procedures. Therefore, the development of reliable, low-cost, rapid, simple, accurate, highsensitive and selective analysis methods of determination for the analysis, identification and purification of environmental and biological media is vital.

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Simplicity, low cost and amenability to miniaturization are inherent advantages of electrochemical methods [16]. Recently, molecular imprinting technology has been used to design biomimetic materials in biorecognition elements based on electrochemical sensors [17-19]. Electrochemical sensors based on molecularly imprinted polymer (MIP) as recognition element take advantages the specific molecular recognition and a highly sensitive electrochemically response simultaneously [17, 18, 20, 21]. MIPs are artificial receptors with selectivity and high affinity in their size, shape and spatial arrangement of functional groups towards the targeted analytes [22-26]. According to imprinting process, a monomer is chosen to interact strongly with the template molecule. A network with specific conformational and structural sites is formed by polymerization and cross-linking of the monomer around this complex. With unique MIP properties including easy preparation, thermal and chemical stability, high reliability, they have been widely applied in analytical separation technologies [27-32], especially biological separation [33]. Using MIP to recognition of biological species in complex matrix reported by different researchers. In fact, MIPs can replace their biological counterparts in real applications [33-37]. Various authors have benefited from such concessions at the same time. For example, Hande et al., reported efficient MIP based carbon paste electrode sensor for the determination of diphenylamine in aged propellant [38]. Alizadeh et al., prepared a new MIP-based carbon paste electrode for monitoring 2,4,6-trinitrotoluene in natural waters and soil samples [39]. Carbon paste electrodes (CPEs) are widely applicable in electrochemical studies due to their low cost, easy preparation, low background current, feasibility to incorporate different substances during the paste preparation, simple renewal of their surface and possibilities of miniaturization [19, 40-43]. Heretofore, according to literature, Zileuton determination in plasma was performed by HPLC [44] and LC/MS-MS [13] methods. Despite the importance of determining the concentration of drug in the plasma, the study of past research has reveals that so far there are no simple selective method for the estimation of Zileuton. For the first time, we present determination and electrochemical behavior of Zileuton in plasma on carbon paste electrode activated by molecularly imprinted polymeric layer.

In this study, electrochemical behavior of Zileuton on a carbon paste electrode modified by MIP was investigated by cyclic voltammetry and differential pulse voltammetry. Determination of Zileuton in human plasma was also studied by cyclic voltammetry. 2. Experimental

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2.1. Materials and Instrument All chemicals include Zileuton (≥98%), Methacrylic Acid (99%, MAA), Ethylene Glycol Dimethacrylate (98%, EGDMA), graphite powder, Azobisisobutyronitrile (98%, AIBN) and Phosphoric Acid (85%) were purchased from Aldrich company. Also, Ethanol (99.8%), Methanol (99.9%), Dimethylsolphoxide (≥99%, DMSO), Disodium Hydrogen Phosphate, Sodium Hydroxide (≥98%), Acetic Acid (≥99%), Trichloroacetic acid (≥99.00%) and paraffin oil was purchased from Sigma-Aldrich company. graphite powder was purchased from fluka company. Drug-free blank human plasma sample was obtained from normal volunteers in Iranian blood transfusion service (Tehran, Iran) and stored at -20 ℃ until analysis. To prepare plasma sample, 5 mL of plasma sample was mixed with 5 mL Trichloroacetic acid 1.2 M. Then the mixture was centrifuge for 15 min with rate of 3000 rpm. Upper transparent solution was filtrated and was volume with water in 50 mL Volumetric flask. Fourier Transform Infrared (FTIR) spectra were recorded on a FT-IR spectrometer Bruker Equinox. Vibrational transition frequencies are reported in the range of 400–4000 cm-1. The cell path length was kept constant during all experiments. The samples were prepared on a KBr pellet at a pressure of 0.01 torr in vacuum desiccators under. Scanning Electron Microscopy (SEM) analysis was performed with a field emission KYKY EM-3200 SEM analyzer with an acceleration voltage of 20 kV and different magnifications of 100-4000. Samples were gold-coated using a sputtering coater. Electrochemical studies were performed using Autolab PGSTAT12N potentiostat/galvanostat controlled by GPES 4.9 software (Eco Chemie, The Netherlands). Three-electrode were used for all measurements: a bare or modified carbon paste electrode as the working electrode, a Pt wire as the auxiliary electrode and a Ag/AgCl, 3 mol L-1 KCl (Metrohm, Switzerland) as the reference electrode. A Metrohm 780 pH/ion meter was also used for pH measurements. The double-distilled water was used for the experiments. 2.2. Preparation of Stock and standard solutions The stock solutions of Zileuton (5 mM) was freshly prepared by dissolving an accurate mass of their powders in an appropriate volume of deionized water: ethanol (80: 20) mixture. Phosphate buffer solutions with different pH (2-11) were prepared with using 0.1 M

solutions of sodium dihydrogen phosphate, disodium hydrogen phosphate, phosphoric acid and sodium hydroxide. The ionic strength is a 0.1 M molar phosphate buffer.

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2.3. Polymer Synthesis Procedure Polymerization was performed by bulk polymerization method. Firstly, Zileuton (7 mg, 0.0296 mmol) and MAA (35 µL, 0.407 mmol) were dissolved in 10 mL DMSO. The prepolymerization was performed at room temperature for 10 min under stirring. Then, EGDMA (5 mL, 25 mmol) and AIBN (0.033 g, 0.2 mmol) were added to the mixture. The mixture was purged with N2 for 15 min and sealed. The reaction was performed in a thermostatic water bath at 60 ℃ for 24 h. The obtained polymer particles were collected by filtration and were ground. Then the obtained powders washed thoroughly with acetic acid (1 M): ethanol with ratio of 9: 1 and at the end, they were washed once with water successively to remove both the template molecules and unreacted monomers. The resultant polymer particles dried at 65 ℃ for 24 h. The corresponding control particles were prepared and purified under identical condition except that the template was omitted.

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2.4 Preparation of the Developed Electrochemical Sensor To prepare the chemically MIP-modified carbon paste (MIPCP) electrode was prepared by completely mixing graphite powder (49 mg) and MIP (14 mg). Then paraffin Oil added droplet in a mortar for at least 20 min so a homogeneous paste was obtained. Subsequently, the obtained paste was packed into the column cavity (diameter 0.32 mm and length 13 mm) of the working electrode. The surface of the electrode was polished with butter paper to ensure a reproducible working surface. By scraping out the old surface and replacing the paste, the electrode surface was renewed. NIP-modified CP (NIPCP) was prepared similarly.

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2.5. Electrochemical Studies All electrochemical studies were performed in phosphate buffer of 0.1 M on the preconcentrated electrodes in the desired scan rate. Pre-concentration processes were performed into Zileuton solution of 5 mM for 10 min. Then the electrode surfaces were washed with deionized water for 2s and transferred to electrochemical cell of the ohm meter to measure voltammetry. The solutions with different pH were prepared by different phosphate buffer with defined concentration. Phosphoric acid and sodium hydroxide were used to control pH of buffer solutions. The selectivity experiments also were carried out using structurally similar Zileuton analogue like Diclofenac, Histidine, Tryptophan and Ascorbic Acid solutions. Experiments were performed at phosphate buffer of 0.1 M at pH of 7 and scan rate of υ = 0.1 V / s.

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3. Result and Discussions 3.1. Polymer Synthesis Non-covalent approach is the most common procedure in use for MIP synthesis because of its simplicity and flexibility to a wide range of functional monomers and possible template molecules [45-47]. In this approach, the efficient non-covalent interaction between template and functional monomer creates shape-memory recognition sites in polymer matrix [48]. This provides interactive functional group randomly situated outside the imprints [49]. In this study the MIP was synthetized via bulk polymerization that is a very environmental friendly polymerization method since no purification is required [22,50]. The MAA was used as suitable functional monomer. Zileuton has different H-bonding positions. So, in this procedure, hydrogen bonding is most prominent interaction of drug with MAA in prepolymerization step. Schematic illustration in preparation of imprinted polymer is presented in Scheme 1. Removement of drug in washing step leads to creation of cavities with Hbonding functional groups. Rebinding of drug accrues in these cavities.

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3.2. Characterization of MIP 3.2.1. Chemical Structure The FTIR spectra of polymers showed peaks, which confirm their chemical structures. the MIP and NIP have rather similar IR spectra (Fig. 2). The FTIR spectrum of the polymers showed the characteristics absorptions at 1730–1735 cm-1 related to C=O stretching [51,52], 1000–1300 cm-1 (C–O–C stretching [53] and confirm the existence the polymerized monomers in the obtained polymers. The stretching of aliphatic C-H groups appears in 29003000 cm-1 [54-57]. Disappearance of strong peaks at 1610–1620 cm-1 also demonstrate the high yield conversion of vinyl groups of the monomers to the polymer [57].

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3.2.2. Morphology SEM analysis presents morphological structure of MIP surface. As shown in Figure 3, the MIP contains bulky species with non-uniform sizes and rough porous surface. Surface morphology of MIP particles presented agglomeration of particles as nano and micro cluster. This morphological surface is most common for MIPs synthetized with bulk polymerization [58,59].

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3.3. Electrochemical Behavior of Zileuton The cyclic voltammetric behavior for Zileuton was investigated on pre-concentrated bare carbon paste electrode. The potential was swept in interval of - 0.5 to +1 V at pH = 7. The cyclic voltammetry is presented in Figure 4. As shown, CPE presented no electrochemical response. This indicates that the bare carbon paste electrode has not bonding sites for Zileuton. To enhance electrochemical responses of electrode for Zileuton CPE was modified with the synthetized MIP. Studying of electrochemical behavior of NIPCP and MIPCP electrodes was performed in the same measurement condition. The presence of two redox peaks can be observed, which also was reported by other authors such as Nabil et al [6]. So, electrochemical behavior of drug on MIPCP and NIPCP, showed relatively reversible behavior with anodic and cathodic peaks. An increase in anodic peak current was indicated for Ziluteon when using MIPCP compared to NIPCP.

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3.4. Imprinting Effect To investigate imprinting effect and formation of porous pores in MIP structure due to presence of Zileuton through polymerization, voltammogram cycle related to MIPCP was studied and compared to NIPCP. The scanning for MIPCP (Fig. 4) showed a voltammetry response. Results indicated that electrochemical behavior of Zileuton on MIPCP presented redox peaks in higher peak currents than NIPCP (anodic and cathodic peaks at 375 mV and 62 mV respectively). It refers to the presence of more pores and binding sites in the developed sensor for Zileuton, a sign of the successful synthesis of polymer matrix with higher binding sites for template compared to NIP that increase redox reaction in the surface of MIPCP [60, 61]. The difference between anodic peak current response of MIPCP electrode (ipa MIP) and anodic peak current response of NIPCP electrode (ipa NIP) as imprinting effect, (ipa MIP - ipa NIP) / ipa MIP = 0.75, represents that in addition to the complementary bindings, the activation of electrode by the polymers (MIP and NIP) was due to the interaction of the target molecule with functional groups on polymers matrix. [62,63]. Therefore, hydrophobic Zileuton molecule tends to enter from the solution to the electrode surface due to the presence of a polymeric layer and recognized by the specific binding sites. 3.5. Effect of pH One of the most effective factor on the electrochemical behavior of materials is pH factor [64-67]. Effect of pH solution on electrochemical behavior of Zileuton was studied over the pH range of 2-11 on MIPCP electrode (Fig. 5). Electrochemical response showed that pH of lower than 3 presented only reduction peak indicating that reduction is occurred at acidic pH because of the protonation and one electron capture (Fig. 5a). So, Zileuton does not

oxidize in acidic media. With increasing pH, oxidation of Zileuton begins so that the most electrochemical response was observed at pH = 7 (Fig. 5b) and anodic/cathodic peaks at pH = 7 were enough clear. Then, at pH = 8-11 the response was decreasing (Fig. 5c). Accordingly, the mechanism of reduction of drug in Scheme 2 is suggested [4, 5].

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The changes of peak current (ip) of reduction and oxidation processes for Zileuton over the pH range from 2 to 11 on MIPCP electrode are presented in Figure 6. The peak current of the cathodic feature (ipc) and also of the oxidative feature (ipa) exhibited high dependence on pH. Results showed decreasing the current at pH ≤ 6 and then a sharp increasing of the current to pH =7 was observed. Then, in higher pH, current was decreased, so pH = 7 was selected as optimum pH.

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Figure 6b indicates relation between cathodic peak potential (Ep) and pH solution. A linear correlation was obtained. It is in accordance with linear equation 1 with the acceptable correlation coefficient being R2 = 0.9539. 𝐸𝑝 (𝑉) = 0.0818 𝑝𝐻𝑏 + 0.9358 (1)

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As shown, oxidative peak potentials shift to lower amount with pH increasing. So, protonation reactions affected electrode processes and as the pH increases, oxidation becomes easier.

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Based on nernst equation, the relationship between Ep and pH is as shown in equation 2: (𝑂𝑋)𝑎 𝐸𝑝 = 𝐸 0 + (0.0591⁄𝑛) 𝑙𝑜𝑔 [ (2) ⁄ )𝑏 ] − (0.0591 𝑚⁄𝑛) pH (𝑅 Where ?? and 𝑏 are the coefficients of reactants and products in the reaction, 𝑚 and 𝑛 are number of protons and electrons transferred in the reaction. Therefore, the value of slope of equation (1) for Zileuton is approximately near to 0.1 V, this indicates, according to equations of (1) and (2), that the number of participant protons in the reaction is twice to the number of electrons.

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3.6. Effect of scan rate The scan rate expresses how fast the applied potential is scanned. The study of dependence of peak current on scan rate at optimum pH = 7 was performed on MIPCP. So, the scan rates of 10, 20, 30, 40, 50, 75, 100, 250 and 500 mV s−1 were examined. The related voltammograms are presented in Figure 7a. Direct relation between scan rate and anodic peak currents was obtained (Fig. 7b). Results indicated that faster scan rates lead to higher currents. Because faster scan rates lead to a decrease in the size of the diff usion layer; therefore, higher currents are observed [68]. To study freely diffusing redox species or

adsorbed on the electrode, the study of relation of the log of peak current ipa (µA) with log of the scan rate υ (mV s−1) showed in Figure 7c that accords with Randles−Sevcik equation (Eq 3) that confirmed an ideal reaction controlled by the diffusion process. 𝑖𝑝 = 0.4463 𝑛 𝐹𝐴𝐶(

𝑛𝐹𝑣𝐷 0.5 ) 𝑅𝑇

(3)

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3.7. Selectivity of the MIPCP Selectivity of MIPCP was studied to determine degree of preferential interaction for Zileuton over analogous compounds. Chemical and physical properties of the studied compounds are shown in Table 1. The selectivity experiments were carried out using Diclofenac, Histidine, Tryptophan and Ascorbic Acid. As can be seen in Figure 8, MIPCP that pre-concentrated in Diclofenac, Histidine, Tryptophan and Ascorbic Acid solutions as analogue structures had no obvious electrochemical response. Results indicated that electrochemical behavior of Zileuton on MIPCP presented anionic peaks in higher current. Presence of MIP on the carbon electrode due to its tendency to drug adsorption led to an electrochemical response. As shown in Figure 9 in spite of increasing hydrophilicity of the compounds, decreasing peak currents. It refers to the separation factor and reflects the selectivity of the developed sensor for Zileuton. The selective recognition by imprinted polymer is related to size and shape memory of cavities for Zileuton structure and also functional groups of imprinted cavities which can interact with the drug by hydrogen bonding. It is a sign of the successful imprinting of the drug molecule in the polymerization process. Looking more closely to the results, Tryptophan is the most similar structurally shape to Zileuton compared to other studied analogue compounds. But despite of more hydrophilicity of Tryptophan (lower log P and higher water solubility) compared to Zileuton, the its response was less indicative. This indicates greater specificity of the MIP for Zileuton. Other compounds, Diclofenac, Histidine and Ascorbic Acid have different from the template molecule and their response were not significant. 3.8. Interference Study After the optimization of the determination method for the prepared MIPCP sensor, in order to investigate effect of the interfering compounds on the detection of Zileuton, several inorganic / organic compounds with different concentrations were added into the 5 mM of Zileuton solution in the established measurement conditions by MIPCP. The maximum concentration of an interference when it yielded a relative error of 5% was considered as the tolerance limit and the mole ratio of the tolerance limit of the interfering (𝐶Species ) and the concentration of Zileuton (𝐶Zileuton ) is the interfering level. The results are shown in Table

2. Interference Level of different organic and inorganic substances were > 1. These results confirmed that MIPCP electrode had satisfactory selectivity toward Zileuton determination. Acid compound (Ascorbic acid, uric acid) showed lowest interference level.

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3.9. Differential Pulse Voltammetry of Zileuton on MIPCP electrode Due to more sensitivity and resolution of DPV method compared to CV method, it used to define limit of detection (LOD) of Zileuton and development of a quantitative voltammetry method. Linear correlation between peak current and drug concentration was investigated. The studies were performed on MIPCP in phosphate buffer at pH = 7 and scan rate of 0.1 mV s−1. The voltammograms of Zileuton solutions with concentration range of 0.1-25 µg mL-1 are presented in Figure 10. As shown all peak potentials are almost constant in 0.551 V. Also, peak currents (ip) data indicated a linear relation with concentration (C) with equation of 𝑖𝑝 (µA) = 0.0216 𝐶 + 0.3439 and correlation coefficient of R2 = 0.9839. In this study, LOD of Zileuton was calculated 0.189 µg mL-1 that confirmed acceptable sensitivity of method. In this study also repeatability of the MIPCP electrode was studied by measuring of Zileuton in solution with concentration of 4 µM for eight times and result indicated RSD equals with 0.912.

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3.10. Analytical Application of Modified Electrode To evaluate the applicability of the proposed method the modified electrode, MIPCP was applied to analyze Zileuton in human plasma sample. The result of the assay in plasma yielded a recovery of > 96% and RSD ≤ 2.65%, (n = 6). A comparison between the analytical characteristics of the present method and some previous reports for the determination of Zileuton is shown in Table 3. The studied modified electrode was presented higher recovery and lower RSD compared to other methods.

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4. Conclusion In this study, a novel and fast-responsive sensor with long-term stability was designed based on MIP/carbon paste electrode to increase electrochemical response of electrode to Zileuton due to its increasing tendency adsorption on the electrode. In this research, MIP was obtained as a pre-concentration agent and a recognitive matrix with high sensitivity. Similarly, the modified sensor can be used to determine Zileuton in complex matrices with the ability to separate and pre-concentrate directly. The prepared sensor exhibited excellent selectivity and sensitivity in template detection because of presence of recognition sites with effective interaction for Zileuton. This demonstrated that this method can be a suitable alternative with an acceptable LOD (0.189 µg mL-1). Also high sufficiency of modified sensor in determination of Zileuton in human plasma matrix with recovery of > 96% confirmed that

the sensor exhibits excellent valid performance for detecting of Zileuton in pharmaceuticals and biological fluids without the supporting of any separation techniques. In fact, in this work, we used simultaneous outstanding features of electrochemical sensors and MIP as highly sensitive response and high selectivity respectively.

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Data availability This section will be sent as needed.

References

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1- A. Rossi, C. Pergola, A. Koeberle, M. Hoffmann, F. Dehm, P. Bramanti, S. Cuzzocrea, O. Werz, L. Sautebin., The 5‐ lipoxygenase inhibitor, zileuton, suppresses prostaglandin biosynthesis by inhibition of arachidonic acid release in macrophages, Br. J. Pharmacol. 161 (3) (2010) 555570, https://doi.org/10.1111/j.1476-5381.2010.00930.x. 2Zyflo Drug Information. 3- S.L. Wong, W.M. Awni, J.H. Cavanaugh, T. El-Shourbagy, C.S. Locke, L.M. Dubé., The pharmacokinetics of single oral doses of zileuton 200 to 800mg, its enantiomers, and its metabolites, in normal healthy volunteers, Clin. Pharmacokinet. 29 (2) (1995) 9-21, https://doi.org/10.2165/00003088-199500292-00004. 4Z.I. Krutetskaya, L.S. Milenina, A.A. Naumova, V.G. Antonov, A.D. Nozdrachev., 5Lipoxygenase inhibitor zileuton inhibits Ca2+-responses induced by glutoxim and molixan in macrophages, Dokl. Biochem. Biophys. 469 (1) (2016) 302-304, https://doi.org/10.1134/S1607672916040177. 5M.R. Baezzat, F. Banavand, F. Fasihi., Highly sensitive determination of zileuton using TiO2 nanoparticles and the ionic liquid 1-hexylpyridinium hexafluorophosphate nanocomposite sensor, Ionics. (2018)1-10, https://doi.org/10.1007/s11581-018-2699-8. 6M.A. Alhemiary, M.A. Rizk., Sensitive and validated voltammetric methods for determination of zilueton in serum, urine and pharmaceutical dosage forms at activated glassy carbon electrode, Asian. J. Chem. 29 (12) (2017) 2627-2633, https://doi.org/10.14233/ajchem.2017.20737. 7N.Y. Sreedhar, M. Sankara Nayak, K. Srinivasa Prasad, P.R. Prasad, C. nageswar reddy., Electrochemical Reduction Behaviour of Zileuton at a Dropping Mercury Electrode by Polarography, Electron. J. Chem. 7 (1) (2010) 166-170, http://dx.doi.org/10.1155/2010/251415. 8- K. Anandakumar, N. Nareshbabu., Development and validation of analytical method for the estimation of zileuton in bulk and in pharmaceutical dosage form by UV spectroscopy, Int. Res. J. Pharm. 3 (12) (2012)154-157, https://irjponline.com/admin/php/uploads/1552_pdf.pdf. 9- S.B. Ganorkar, A.A. Shirkhedkar., Novel HPTLC and UV-AUC analyses: For simple, economical, and rapid determination of Zileuton racemate, Arab. J. Chem. 10 (3) (2017) 360367, http://dx.doi.org/10.1016/j.arabjc.2013.05.013. 10- S.B. Ganorkar, D.M. Dhumal, A.A. Shirkhedkar., Application of UV-Spectrophotometry for Determination of Zileuton in Bulk and in Tablets, Indian Drugs. 50 (6) (2013) 40-43, https://www.indiandrugsonline.org/issuesarticle-details?id=MzEx. 11- K.V.P. Rao, M. Tanuja, Y.S. Rao, T.H. Kumar., Visible spectrophotometric methods for determination of zileuton in bulk drug and pharmaceutical formulation, Int. j. res. pharm. Chem. 5 (2) (2015) 251-257, http://www.ijrpc.com. 12S.B. Ganorkar, D.M. Dhumal, and A.A. Shirkhedkar., Development and validation of simple RP-HPLC-PDA analytical protocol for zileuton assisted with Design of Experiments for robustness determination, Arab. J. Chem. 10 (2) (2017) 273-282, https://doi.org/10.1016/j.arabjc.2014.03.009. 13- K. Prakash, S.K. Adiki, R.R. Kalakuntla., Development and Validation of a Liquid Chromatography-Mass Spectrometry Method for the Determination of Zileuton in Human Plasma, Sci. Pharm. 82 (3) (2014) 571-584, https://doi.org/10.3797/scipharm.1402-19. 14- K. Vara Prasada Rao, M. Tanuja, Y. Srinivasa, T. Rao, Hemant Kumar., Development and Validation of RP-HPLC method for the estimation of Zileuton in bulk and its dosage form, Int. j. drug dev. Res. 7 (1) (2015) 101-106, http://www.ijddr.in. 15- S.B. Thomas, S.J. Albazi., Simultaneous Determination of the 5-Lipoxygenase Inhibitor “Zileuton” and its N-Dehydroxylated Metabolite in Untreated Rat Urine by Micellar Liquid

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Chromatography, J. Liq. Chromatogr R T. 19 (6) (1996) 977-991, https://doi.org/10.1080/10826079608001928. 16J. Svítková, M. Machková, P. Šatkovská, K. Cinková, Ľ. Švorc., Utilization of electrochemical methods in determination of trace elements in beverages, Acta Chimica Slovaca. 5 (1) (2012) 42-46, https://doi.org/10.2478/v10188-012-0007-1. 17M.K.L. Coelho, J.D.F. Giarola, A.T.M. da Silva, C.R.T. Tarley, K.B. Borges, A.C. Pereira., Development and application of electrochemical sensor based on molecularly imprinted polymer and carbon nanotubes for the determination of carvedilol, Chemosensors. 4 (4) (2016) 22, https://doi.org/10.3390/chemosensors4040022. 18C.R.T. Tarley, M.D.P.T. Sotomayor, L.T. Kubota., Biomimetic polymers in analytical chemistry. Part 2: applications of MIP (Molecularly Imprinted Polymers) in the development of chemical sensors, Quim. Nova. 28 (6) (2005) 1087–1101, http://dx.doi.org/10.1590/S010040422005000600025. 19- M.R. Ganjali, T. Alizade, B. Larijani, F. Faridbod, P. Norouzi., Nano-composite clozapine potentiometric carbon paste sensor based on biomimetic molecular imprinted polymer, Int. J. Electrochem. Sci. 7 (5) (2012) 4756-4765. 20- M.F. Frasco, L.A. Truta, M.G.F. Sales, F.T. Moreira., Imprinting technology in electrochemical biomimetic sensors, Sensors. 17 (3) (2017), 523. https://doi.org/10.3390/s17030523. 21M.C. Blanco-López, M.J. Lobo-Castañón, A.J. Miranda-Ordieres, P. Tuñón-Blanco., Electrochemical sensors based on molecularly imprinted polymers, TrAC Trends Anal. Chem. 23 (1) (2004) 36–48, https://doi.org/10.1016/S0165-9936(04)00102-5. 22- W. Ji, M. Zhang, Q. Gao, L. Cui, L. Chen, X. Wang., Preparation of hydrophilic molecularly imprinted polymers via bulk polymerization combined with hydrolysis of ester groups for selective recognition of iriDOId glycosides, Anal. Bioanal. Chem. 408 (19) (2016) 5319-5328, https://doi.org/10.1007/s00216-016-9625-6. 23T. Takeuchi, D. Fukuma, J. Matsui., Combinatorial molecular imprinting: an approach to synthetic polymer receptors, Anal. Chem. 71 (2) (1999) 285-290, https://doi.org/10.1021/ac980858v. 24J. Pan, W. Chen, Y. Ma, G. Pan., Molecularly imprinted polymers as receptor mimics for selective cell recognition, Chem. Soc. Rev. (15) (2018), https://doi.org/10.1039/C7CS00854F. 25- E. Abdollahi, M. Abdouss, M. Salami-Kalajahi, A. Mohammadi., Molecular recognition ability of molecularly imprinted polymer nano-and micro-particles by reversible additionfragmentation chain transfer polymerization, Polym Rev. 56 (4) (2016) 557-583, https://doi.org/10.1080/15583724.2015.1119162. 26- M.S. da Silva, F.L. Nobrega, A. Aguiar-Ricardo, E.J. Cabrita, T. Casimiro., Development of molecularly imprinted co-polymeric devices for controlled delivery of flufenamic acid using supercritical fluid technology, J. Supercrit. Fluids. 58 (1) (2011) 150-157, https://doi.org/1016/j.supflu.2011.05.010. 27- A.R.C. Duarte, T. Casimiro, A. Aguiar-Ricardo, A.L. Simplício, C.M. Duarte., Supercritical fluid polymerisation and impregnation of molecularly imprinted polymers for drug delivery, J. Supercrit. Fluids. 39 (1) (2006) 102-106, https://doi.org/10.1016/j.supflu.2006.01.013. 28- R.C. Advincula., Engineering molecularly imprinted polymer (MIP) materials: Developments and challenges for sensing and separation technologies, Korean J. Chem. Eng. 28 (6) (2011) 1313-1321, https://doi.org/10.1007/s11814-011-0133-2. 29L. Zhu, L. Chen, X. Xu., Application of a molecularly imprinted polymer for the effective recognition of different anti-epidermal growth factor receptor inhibitors, Anal. Chem. 75 (23) (2003) 6381-6387, https://doi.org/10.1021/ac026371a.

A

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M

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30M. Rutkowska, J. Płotka-Wasylka, C. Morrison, P.P. Wieczorek, J. Namieśnik, M. Marć., Application of molecularly imprinted polymers in an analytical chiral separation and analysis, Trends Anal. Chem. 102 (2018) 91-102, https://doi.org/10.1016/j.trac.2018.01.011. 31- M. Lachová, J. Lehotay, J. Cizmárik., Applications of molecularly imprinted polymers in analytical and pharmaceutical chemistry. Ceska a Slovenska farmacie: casopis Ceske farmaceuticke spolecnosti a Slovenske farmaceuticke spolecnosti. 56 (4) (2007) 159-164. https://www.ncbi.nlm.nih.gov/pubmed/17969313. 32- L.I. Andersson., Molecular imprinting: developments and applications in the analytical chemistry field, J. Chromatogr. B. 745 (1) (2000) 3-13, https://doi.org/10.1016/S03784347(00)00135-3. 33E. Abdollahi, M. Abdouss, A. Mohammadi., Synthesis of a nano molecularly imprinted polymeric sorbent for solid phase extraction and determination of phenytoin in plasma, urine, and wastewater by HPLC, RSC Advances. 6 (45) (2016) 39095-39105, https://doi.org/10.1039/C6RA00421K. 34- J.H. Helbig, B. Ludwig, P.C. Lück, A. Groh, W. Witzleb, J. Hacker., Monoclonal antibodies to Legionella Mip proteins recognize genus-and species-specific epitopes, Clin Diagn Lab Immunol. 2 (2) (1995) 160-165. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC170120. 35- J. Pan, H. Yao, L. Xu, H. Ou, P. Huo, X. Li, Y. Yan., Selective recognition of 2, 4, 6trichlorophenol by molecularly imprinted polymers based on magnetic halloysite nanotubes composites, J. Phys. Chem. C. 115 (13) (2011) 5440-5449, https://doi.org/ 10.1021/jp111120x. 36- A. Cumbo, B. Lorber, P.F.X. Corvini, W. Meier, P. Shahgaldian., A synthetic nanomaterial for virus recognition produced by surface imprinting, Nat Commun. 4 (2013) 1503, https://doi.org/10.1038/ncomms2529. 37- H.F. El-Sharif, D. Stevenson, S.M. Reddy., MIP-based protein profiling: A method for interspecies discrimination, Sens. Actuators B-Chem. 241 (2017) 33-39, https://doi.org/10.1016/j.snb.2016.10.050. 38P.E. Hande, A.B. Samui, P.S. Kulkarni., An Efficient Method for Determination of the Diphenylamine (Stabilizer) in Propellants by Molecularly Imprinted Polymer based Carbon Paste Electrochemical Sensor, Propellants Explos. Pyrotech. 42 (4) (2017) 376-380, https://doi.org/10.1002/prep.201600118.’ 39T. Alizadeh, M. Zare, M.R. Ganjali, P. Norouzi, B.K Tavana., A new molecularly imprinted polymer (MIP)-based electrochemical sensor for monitoring 2,4,6-trinitrotoluene (TNT) in natural waters and soil samples, Biosens. Bioelectron. 25 (2010) 1166– 1172, https://doi.org/10.1016/j.bios.2009.10.003. 40- C. Apetrei, I.M. Apetrei, J.A.D. Saja, M.L. Rodriguez-Mendez., Carbon paste electrodes made from different carbonaceous materials: application in the study of antioxidants, Sensors. 11 (2) (2011) 1328-1344, https://doi.org/10.3390/s110201328. 41- M.R. Baezzat, F. Banavand, F. Fasihi., Electrooxidation study and highly sensitive voltammetric determination of alfuzosin employing multi-walled carbon nanotubes and the ionic liquid 1-hexylpyridinium hexafluorophosphate nanocomposite sensor, J. Mol. Liq. 233 (2017) 391-397, https://doi.org/10.1016/j.molliq.2017.02.119. 42- Z. Stanic, S. Girousi., Carbon paste electrodes in potentiometry: the state of the art and applications in modern electroanalysis (A review), Sens. Electroanal. 6 (2011) 89-128. 43- R. Pourghobadi, M.R. Baezzat., Silica Nanoparticles Modified Carbon Paste Electrode as a Voltammetric Sensor for Determination of Diclofenac, Anal Bioanal Chem Res. 4 (2) (2017) 261-268, https://doi.org/10.22036/abcr.2017.69226.1124. 44- G.R. Granneman, R.A. Braeckman, K.A. Erdman., Determination of a new 5-lipoxygenase inhibitor, zileuton, and its inactive N-dehydroxylated metabolite in plasma by high performance liquid chromatography, Clin Pharmacokinet. 29 (2) (1995) 1-8, https://doi.org/10.2165/00003088-199500292-00003.

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45- E. Abdollahi, A. Khalafi-Nezhad, A. Mohammadi, M. Abdouss, M. Salami-Kalajahi., Synthesis of new molecularly imprinted polymer via reversible addition fragmentation transfer polymerization as a drug delivery system, Polymer. 143 (2018) 245-257, https://doi.org/10.1016/j.polymer.2018.03.058. 46- E. Yilmaz, R.H. Schmidt; K. Mosbach., Approaches to Molecularly Imprinted Polymers-The Noncovalent Approach. In Molecularly Imprinted Materials: Science and Technology; Yan, M.; Ramström, O., Eds.; CRC Press, (2004) 25–58. 47- R. Arshady, K. Mosbach., Synthesis of Substrate-Selective Polymers by Host-Guest Polymerization. Makromol. Chem., 182 (1981) 687–692. 48- H. Zhang, T. Piacham, M. Drew, M. Patek, K. Mosbach, L. Ye., Molecularly imprinted nanoreactors for regioselective huisgen 1, 3-dipolar cycloaddition reaction, J. Am. Chem. Soc. 128 (13) (2006) 4178-4179, https://doi.org/10.1021/ja057781u. 49- N. Suda, H. Sunayama, Y. Kitayama, Y. Kamon, T. Takeuchi., Oriented molecularly imprinted cavities with dual binding sites for highly sensitive and selective recognition of cortisol, R Soc Open Sci. 4 (8) (2017) 170300, https://doi.org/10.1098/rsos.170300. 50S.A. Mohajeri, G. Karimi, J. Aghamohammadian., M. R. Khansari., Clozapine recognition via molecularly imprinted polymers; bulk polymerization versus precipitation method, J. Appl. Polym. Sci. 121(6) (2011) 3590-3595, https://doi.org/10.1002/app.34147. 51- F. Rafiemanzelat, E. Abdollahi., Synthesis and characterization of hydrolysable poly (ether– urethane–urea) s derived from l-leucine anhydride cyclopeptide; a green synthetic method for monomer, Polym. Degrad. Stab. 95 (6) (2010) 901-911, https://doi.org/10.1016/j.polymdegradstab.2010.03.030. 52- F. Rafiemanzelat, E. Abdollahi., Rapid synthesis of new block copolyurethanes derived from L‐ leucine‐ PEG in ionic liquids under microwave irradiation, J. Appl. Polym. Sci. 123 (2) (2012) 1015-1023, https://doi.org/10.1002/app.34691. 53- F. Rafiemanzelat, E. Abdollahi., Rapid synthesis of new block copolyurethanes derived from l-leucine cyclodipeptide in reusable molten ammonium salts: novel and efficient green media for the synthesis of new hydrolysable and biodegradable copolyurethanes, Amino acids. 42 (6) (2012) 2177-2186, https://doi.org/10.1007/s00726-011-0957-4. 54- E. Abdollahi, M. Abdouss, M. Salami-Kalajahi, A. Mohammadi, A. Khalafi-Nezhad., Synthesis and characterization of diethyl-dithiocarbamic acid 2-[4-(2diethylthiocarbamoylsulfanyl-2-phenyl-acetyl)-2, 5-dioxo-piperazin-1-yl]-2-oxo-1-phenylethyl ester as new reversible addition-fragmentation chain transfer agent for polymerization of ethyl methacrylate, Des Monomers Polym. 19 (1) (2016) 56-66, https://doi.org/10.1080/15685551.2015.1092013. 55- F. Rafiemanzelat, A.F. Zonuz, E. Abdollahi., Fast and eco-friendly synthesis of new hydrolysable and biodegradable copolyurethanes derived from L-leucine cyclodipeptide and different molecular weights of PEG in TBAB under microwave irradiation, Macromol Res. 20 (9) (2012) 902-911, https://doi.org/10.1007/s13233-012-0137-8. 56- F. Rafiemanzelat, E. Abdollahi, M. Moghadam, V. Mirkhani, S. Tangestaninejad, I. Mohammadpoor‐ Baltork., Application of tin (IV) porphyrin complexes as novel catalysts for the synthesis of new copolyurethanes with cyclopeptide moiety, J. Appl. Polym. Sci. 124 (1) (2012) 638-646, https://doi.org/10.1002/app.35022. 57- S. Hassanajili, E. Abdollahi., Influence of various reaction media on the thermal and rheological properties of poly (acrylamide‐ co‐ N‐ hexadecylacrylamide), J. Appl. Polym. Sci. 131 (6) (2014), https://doi.org/10.1002/app.39939. 58- P. Sikiti, T.A. Msagati, B.B. Mamba, A.K. Mishra., Synthesis and characterization of molecularly imprinted polymers for the remediation of PCBs and dioxins in aqueous

A

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EP

TE

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A

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environments, J. Environ. Health Sci. Eng. 12 (2014) 82, https://doi.org/10.1186/2052-336X12-82. 59S. Daniel, P.P. Rao, T.P. Rao., Investigation of different polymerization methods on the analytical performance of palladium (II) ion imprinted polymer materials, Anal Chim Acta, 536 (1-2) (2005) 197-206, https://doi.org/10.1016/j.aca.2004.12.052. 60- M. Khadem, F. Faridbod, P. Norouzi, A. Rahimi Foroushani, M.R. Ganjali, S.J. Shahtaheri, R. Yarahmadi., Modification of carbon paste electrode based on molecularly imprinted polymer for electrochemical determination of diazinon in biological and environmental samples, Electroanal. 29 (3) (2017) 708-715, https://doi.org/10.1002/elan.201600293. 61- M. Khasanah, H. Darmokoesoemo, D.A. Rizki., Carbon paste electrode modified molecularly imprinted polymer as a sensor for creatinine analysis by stripping voltammetry. In AIP Conference Proceedings. 1888 (2017) 020033. AIP Publishing, https://doi.org/10.1063/1.5004310. 62- T. Zhou, Y. Tao, H. Jin, B. Song, T. Jing, D. Luo, Y. Zhou, Y. Zhou, Y.I. Lee, S. Mei., Fabrication of a selective and sensitive sensor based on molecularly imprinted polymer/acetylene black for the determination of azithromycin in pharmaceuticals and biological samples, PloS one. 11 (1) (2016) e0147002, https://doi.org/10.1371/journal.pone.0147002. 63X.J. Wang, Z.L. Xu, J.L. Feng, N.C. Bing, Z.G. Yang., Molecularly imprinted membranes for the recognition of lovastatin acid in aqueous medium by a template analogue imprinting strategy, J Membrane Sci. 313 (1-2) (2008) 97-105, https://doi.org/10.1016/j.memsci.2007.12.067. 64J. Huang, X. Wu, E. H. Han., Influence of pH on electrochemical properties of passive films formed on Alloy 690 in high temperature aqueous environments, Corros Sci. 51 (12) (2009) 2976-2982, https://doi.org/10.1016/j.corsci.2009.08.002. 65D.J. Kim, H.C. Kwon, H.P. Kim., Effects of the solution temperature and the pH on the electrochemical properties of the surface oxide films formed on Alloy 600, Corros Sci. 50 (5) (2008) 1221-1227, https://doi.org/10.1016/j.corsci.2008.01.008. 66H. Sun, X. Wu, E.H. Han, Y. Wei., Effects of pH and dissolved oxygen on electrochemical behavior and oxide films of 304SS in borated and lithiated high temperature water, Corros Sci. 59 (2012) 334-342, https://doi.org/10.1016/j.corsci.2012.03.022. 67- P.L. Runnels, J.D. Joseph, M.J. Logman, R.M. Wightman., Effect of pH and surface functionalities on the cyclic voltammetric responses of carbon-fiber microelectrodes, Anal. Chem. 71 (14) (1999) 2782-2789, https://doi.org/10.1021/ac981279t. 68N. Elgrishi, K.J. Rountree, B.D. McCarthy, E.S. Rountree, T.T. Eisenhart, J.L. Dempsey., A Practical Beginner’s Guide to Cyclic Voltammetry, J Chem Educ. 95 (2) (2017) 197-206, https://doi.org/10.1021/acs.jchemed.7b00361. 69K. Prakash, S.K. Adiki, R.R. Kalakuntla., Development and Validation of a Liquid Chromatography-Mass Spectrometry Method for the Determination of Zileuton in Human Plasma, Sci. Pharm. 82 (3) (2014) 571-583, https://doi.org/10.3797/scipharm.1402-19.

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Figure 1. Chemical structure of Zileuton.

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Figure 2. FTIR Spectra of the washed NIP (a) and MIP (b).

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Figure 3. SEM micrographs of the synthetized MIP.

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Figure 4. Cyclic voltammograms of Zileuton on the CPE, MIPCP and NIPCP electrodes whit scanning rate of 0.1 V / s under air at pH = 7.

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Figure 5. Cyclic voltammograms of Zileuton on MIPCP electrode at different pH of 2-11 whit scanning rate of 0.1 V / s.

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Figure 6. a) pH dependence of peak current for oxidation and reduction Zileuton on MIPCP electrode at pH = 2-11 whit scanning rate of 0.1 V / s. b) relation between cathodic Ep and pH solution.

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Figure 7. a) Cyclic voltammograms of Zileuton solution on MIPCP at pH = 7 at scan rates of 10500 mV s−1., b) Direct correlation between scan rate υ (mV s−1) and anodic peak currents ipa (µA) on MIPCP., c) Linear correlation between the log of peak current ipa (µA) with log of the scan rate υ (mV s−1) on MIPCP.

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Figure 8. Cyclic voltammograms of different compounds of Diclofenac, Histidine, Tryptophan and Ascorbic Acid on MIPCP electrode at pH =7 and scan rate of 0.1 V/s.

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Figure 9. Water solubility and oxidation peak current response of the studied compounds.

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Figure 10. (a) Differential Pulse Voltammograms of Zileuton of 0.8-100 µM solutions on MIPCP electrode in phosphate buffer at pH = 7, and (b) Calibration curve of peak current for Zileuton oxidation.

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Scheme 1. Schematic illustration of Zileuton imprinting process.

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Scheme 2. Proposed mechanism for Zileuton reduction.

Table 1. Chemical and physical properties of the studied compounds. Chemical Structure

Zileuton (C11H12N2O2S)

MW (g mol-1)

pKa

Log Pow

Water Solubility (mg mL-1)

Response Ip (µA)

236.29

8.84

0.9

0.0539 (Practically insoluble)

42

2.38

-1.1

1.36

2*

0.00447

1.5*

62

4*

245.0

3*

Tryptophan (C11H12N2O2)

296.148

4

4.98

Histidine (C6H9N3O2)

155.1546

2.76

- 3.1

Ascorbic acid (C6H8O6)

176.12

4.36

A M

Response is reported in voltage of 0.75V.

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Diclofenac (C14H11Cl2NO2)

D

*

204.23

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Compound

-1.6

Table 2. Results of interference effect of various species on determination of Zileuton by MIPCP at pH = 7. 𝑪 Interference Level* ( 𝐒𝐩𝐞𝐜𝐢𝐞𝐬⁄𝑪

Species

100

2− − 1− SO2− 4 , CO3 , I , Cl

500

Ca2+, Na+, Ba2+, Mg2+, K+

800

)

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Fe3+, Pb2+, Fe2+, Cu 2+

𝐙𝐢𝐥𝐞𝐮𝐭𝐨𝐧

5

Ascorbic acid, Uric acid

500

Glucose, Maltose, Sucrose *

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Interference Level: the mole ratio of the of the interfering concentration (𝐶Species ) to the Zileuton concentration (𝐶Zileuton ) is as interfering level.

Table 3. Comparison of MIPCP electrode with some of the previously reported measurement methods for determination of Zileuton in human plasma. References

Method

Spike sample Relative concentration Standard (µg/mL) Deviation

HPLC

0.01 to 10.0

*

77.9 ± 1.7

[69]

HPLC-Mass

0.007 to16

*

83.4 ±11.6

4

0.052 20

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MIP-modified electrode

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The Studied Modified Electrode Studied Modified Electrode *Not reported.

Liquid Chromatography-Mass Spectrometry MIP-modified electrode

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[44]

[13]

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Recovery %

99.78

2.27

96.5

2.65

99.96