- Email: [email protected]
Ultrasound-assisted Ta2O5 nanoparticles and their photocatalytic and biological applications
Microchemical Journal 147 (2019) 749–754
Contents lists available at ScienceDirect
Microchemical Journal journal homepage: www.elsevier.com/locate/microc
Ultrasound-assisted Ta2O5 nanoparticles and their photocatalytic and biological applications
T
G. Nagaraju , K. Karthik, M. Shashank ⁎
Energy Materials Research Laboratory, Department of Chemistry, Siddaganga Institute of Technology, Tumakuru 572 103, India
ARTICLE INFO
ABSTRACT
Keywords: Ta2O5 nanoparticles Ultrasound-assisted synthesis Photocatalytic activity Antibacterial Anticancer studies
Ta2O5 nanoparticles were synthesized by ultrasound-assisted method. The prepared nanoparticles were characterized structurally by XRD, Raman and morphologically by SEM and TEM. From the XRD pattern, orthorhombic phase Ta2O5 was observed. Raman studies confirm the presence of TaeO at 613 cm−1. TEM images show the average particle size of about 21 nm. Band gap of Ta2O5 nanoparticles were carried out by UV-DRS and found to be 3.12 eV. Photocatalytic activity of Ta2O5 nanoparticles have been examined for the degradation of methylene blue dye and shows 96% degradation after 2 h under visible light irradiation. Ta2O5 nanoparticles also exhibited good antibacterial activity against the foodborne pathogens and anti-breast cancer (MCF-7: IC50: 45.04 μg/mL) activity.
1. Introduction Dyes are the dominant pollutants in the aquatic environment which are toxic and hazardous to many organisms because of decoloration, slow biological degradation, and high chemical oxygen demand [1,2]. In industries, nearly 1,00,000 different types of commercially available dyes have been using used most frequently. Around 15% of the dyes produces annually more than 70,000 tons which are mainly derived from coal tar and petroleum intermediates and are discharged into water bodies without any treatment [3]. The textile, paper, plastic, leather tanning, food, and cosmetic industries are the major cause of the production of waste in water including electrochemical cells and light reaping arrays. Synthetic dyes (azo dyes) acquire large group as colorants (~50–70%) and in industries, 50% of azo dyes were used. Anthraquinone dyes are following next to azo dyes [4,5]. Semiconductor photocatalyst and their heterostructures have been extensively used for decontamination of water caused by various industries under light radiations [6–23]. From past few years, several physical, chemical, and biological methods were adopted for wastewater treatment including reverse osmosis, adsorption, ultrafiltration, coagulation-flocculation, chlorination, ozonation, and biodegradation (microbial) etc. [24,25]. Though, some of these methods cause secondary pollution by transferring organic pollutant from wastewater to another phase. Except for these methods, photocatalytic processes appear as the most promising and widely used technology for the purification of contaminants (organic pollutants) under ambient conditions
⁎
using solar radiation as a source of energy. This is an environmentally friendly method which utilizes radiation as energy. Nevertheless, using metal oxide nanoparticles application of the photocatalytic process is limited to few studies for the remediation of wastewater [26]. Several metal oxide nanoparticles suggest superior photocatalytic, antibacterial, and anticancer performance towards the organic dye degradation, human pathogenic bacteria and cancer cell lines. Metal oxide nanoparticles are widely used because of a simple and less tedious experimental procedure and also non-toxic. Ta2O5 has extensive applications such as optoelectronics, sensors, battery and biological activities. Ta2O5 is a p-type semiconductor (3.8–5.3 eV) with cubic structure. Ta2O5 nanomaterials broadly studied because of its large dielectric and electrochemical properties [27]. This article reports the novel synthesis of Ta2O5 nanoparticles via ultrasonication method at lab temperature without using any surfactant. The structurally characterized and optically studied calcined Ta2O5 nanoparticle materials were examined for various applications including photocatalytic activity, antibacterial activity and anticancer applications. 2. Experimental 2.1. Preparation of Ta2O5 0.5 g TaCl5 was dispersed in 20 mL absolute ethanol and stirred for 1 h. Then 1 mL of double distilled water was added to the above
Corresponding author. E-mail address: [email protected] (G. Nagaraju).
https://doi.org/10.1016/j.microc.2019.03.094 Received 3 December 2018; Received in revised form 12 March 2019; Accepted 29 March 2019 Available online 30 March 2019 0026-265X/ © 2019 Published by Elsevier B.V.
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
solution. Further, the mixed solution was exposed to high-intensity ultrasonic irradiation (frequency: 40 kHz and power: 50 W) (Digital Ultrasonic Cleaner LUMC-2) for 60 min. The precipitate was centrifuged and washed with distilled water and ethanol several times. The sample was dried under vacuum at 70 °C for about 6 h. The obtained powder was calcinated at 800 °C for 2 h. 2.2. Characterization Ultrasound-assisted Ta2O5 nanoparticles was identified using Smart lab X-ray diffractometer (CuKα, λ = 1.5406 Å). The molecular structure was confirmed by Peak Seeker Raman Spectrometer. The surface morphology was examined by SEM (VEGA 3 TESCAN SEM). Particle sizes and crystalline nature were studied by HRTEM (JEOL/JEM 2100). 2.3. Photocatalytic activity setup The photodegradation activity of the Ta2O5 nanoparticles was carried out by measuring the degradation of Methylene blue (MB) dye in aqueous solution under visible light. In photocatalytic degradation experiment, 100 mL of known concentration of methylene blue was taken in glass tube followed by the addition of known quantity of Ta2O5 photocatalyst. During visible light irradiation, at an interval of 30 min the aqueous sample was collected from the reaction mixture and centrifuged to remove the catalyst. UV–Vis absorption spectrophotometer was used to observe the decrease in the absorbance with degradation of MB dyes at 664 nm (λmax). The dye degradation percentage was calculated by using the following relation
=
C0
Ct C0
× 100
Fig. 1. XRD pattern of ultrasound-assisted Ta2O5 nanoparticles.
having the size of ~20 nm. HRTEM (Fig. 2c) images exhibits the interlayer spacing of 2.3 Å which demonstrates the growing direction along (1111). SAED pattern (Fig. 2d) suggests the good crystallinity of the prepared materials. The optical properties of Ta2O5 nanoparticles (Fig. SI-3a) were studied using UV–Visible diffused reflectance spectroscopy (UV-DRS). Using Kubelka-Munk relation the energy band gap was approximately calculated from optical reflectance values. A graph of [F(R)]2 vs. hυ plotted and the obtained intercept gives the bandgap energy. The Kubelka-Munk relation is given below
(1)
F (R ) =
Here, η is the degradation percentage, C0 is the initial absorbance of dye (mg/L); Ct is the change in absorbance of the dye at selected intervals of the degradation (mg/L).
(1
R)2 2R
(2)
Fig. SI-3b gives the projected optical energy band gap of Ta2O5 nanoparticles and was found to be 3.12 eV which is lower when compared with the reported value for the bulk Ta2O5 (3.8 eV) [35]. Room temperature photoluminescence spectrum of Ta2O5 nanoparticles was performed and the result is shown in Fig. SI-4. The peak at 325 nm corresponds to the UV emission. The emission peaks at 444 and 482 nm are originated from the irradiative recombination of free electrons. The peak at 535 nm is assigned to the green emission [36]. Photocatalytic activity of Ta2O5 nanoparticles was assessed by degradation of methylene blue (MB) dye as a targeted pollutant beneath visible light radiations. During the degradation process, absorption maxima gradually decreased in the presence of Ta2O5 nanoparticles at different interval of time at λmax = 664 nm (Fig. 3). In dark there is no degradation was observed for MB and also in the absence of the catalyst; MB exhibits trivial self-degradation (3%) under visible light illumination. The photocatalytic activity was enhanced gradually to 96% in 120 min. The kinetics performance of Ta2O5 nanoparticles for the degradation of MB was performed. Langmuir-Hinshelwood model (Eq. (3)) was used to understand the photodegradation kinetics of MB, this model describes rate constant of photodegradation of the MB.
2.4. Antibacterial activity assay The antibacterial study was carried out using the same procedure (disc diffusion method) published in the previous paper [28]. 2.5. Anticancer activity assay Procedure for the anti-breast cancer activity of Ta2O5 nanoparticles is referred to the articles published by Karthik et al. and Mosmann et al. [29,30]. 3. Results and discussion 3.1. Structural and morphological studies Fig. 1 represents the X-ray diffraction pattern of the prepared Ta2O5 nanoparticles calcined at 800 °C. All the diffraction peaks match well with the characteristic reflections. Formation of the orthorhombic structure with sharp peaks and planes were observed, which indicates the p2mm space group symmetry with the formation of a single phase (JCPDS Card No. 25-0922) without any secondary phase. The average crystallite size (D) was calculated using the Debye-Scherrer equation [31] and found to be ~30 nm. k D = Cos Raman studies of Ta2O5 nanoparticles are shown in Fig. SI-1. Raman peaks at 251, 613 and 840 cm−1 are corresponding to the OeTaeO bending vibrations in TaO6 octahedra and symmetric stretching of the various TaeO bonds [32–34]. SEM images (Fig. SI-2a) shown that particles are agglomerated. EDS spectrum validates the occurrence of Ta and O (Fig. – SI 2b). TEM images (Fig. 2a,b) clearly shows the presence of almost spherical shape
(3)
ln(C 0 / C t) = Kt
where C0 is the initial absorbance of MB dye at time t = 0, Ct is the change in absorbance of MB dye at selected intervals of degradation, and k is the first order rate constant. The photocatalytic activity of Ta2O5 nanoparticles with k value is 1.16 × 10−2 min−1. 3.2. Photodegradation mechanism Degradation mechanism of dye solution was stated in the following equations.
Ta2O5 + h (Vis) 750
Ta2O5 (e
CB
+ h+ VB)
(4)
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
Fig. 2. (a & b) TEM images, (c) HRTEM images and (d) SAED pattern of Ta2O5 nanoparticles.
recombination of e−/h+ pairs and takes part in the oxidation process; hence, it maintains the electron neutrality in Ta2O5. The protonation of %O2− gives hydroperoxyl radicals and forms hydrogen peroxide (H2O2), then %OH radicals will be produced after the dissociation of H2O2 (Eq. (6)–(8)). The organic molecules attacked by the reactive species produced on the surface of the Ta2O5 nanoparticles which act as a strong oxidizing agent [37,38]. The mineralization of organic molecules occurs when these reactive species attack them and forms carbon dioxide and the water molecule (Eq. (10)). Table 1 shows the photocatalytic degradation efficiency of ultrasound-assisted Ta2O5 nanoparticles for (MB dye) is compared with reported values. Table 1 summarizes the Photocatalytic activities of the methylene blue dye using various transition metal oxide nanoparticles. The antibacterial activity of ultrasound-assisted Ta2O5 nanoparticles were performed against gram-positive (S. aureus) gram-negative (E. coli, P. aeruginosa, K. pneumoniae, S. flexneri and S. typhi) bacterial strains (Fig. 4). The most significant antibacterial effect of nanoparticles was found for the concentration of 50 μg/mL per disc against K. pneumoniae to produce inhibition zone of 25 mm. The efficiency of the antibacterial activity of prepared nanomaterials mainly depends on the following factors viz.
Fig. 3. Photocatalytic absorbance spectrum of Ta2O5 nanoparticles.
Ta2O5 (e
CB)
+ O2
H2 O2
(5)
HOO
(6)
H2 O2 + O2
(7)
O2 + H+ 2HOO
O2
HO + H+
Ta2O5 + H2 O
Dye + HO + O2 Dye + Ta2O5
CO2 + H2 O (Byproduct)
Table 1 Photocatalytic degradation efficiency (MB dye) of ultrasound-assisted Ta2O5 nanoparticles compared with reported values.
(9) (10)
VB)
Oxidation product
(11)
Sample
Degradation efficiency (%)
Reference
CB)
Reduction product
(12)
Ta2O5 Ta2O5 W-Ta2O5 CeO2 CuO NiO Mn3O4 SnO2 ZnS Cu doped ZnS Ta2O5
39 23 91 77 15 55 26 83 23 73.5 96
[39] [40] [41] [42] [42] [42] [42] [42] [43] [43] Present work
(h+
Dye + Ta2O5 (e
I. Production of reactive oxygen species (ROS)
(8)
2HO
The photodegradation originates when the visible light irradiated on the Ta2O5 photocatalyst, which leads to the excitation of electrons from VB to a new energy level CB leaving holes in VB (Eq. (4)). In the VB same amount of holes produced simultaneously which react with the water surface or hydroxyl ion to produce hydroxyl radicals (%OH). Simultaneously superoxide radicals (%O2−) through reduction produced when the dissolved oxygen molecules reacts with the electrons in the CB on the surface of the NPs (Eq. (5)). This radical avoids the 751
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
Fig. 4. Antibacterial activity of Ta2O5 nanoparticles against food borne pathogens (M1: 25 μg/mL and M2: 50 μg/mL).
Fig. 5. Cytotoxicity of ultrasound-assisted Ta2O5 nanoparticles against human breast cancer cell line MCF-7. Table 2 Antimicrobial activity of ultrasound-assisted Ta2O5 nanoparticles against bacterial pathogenic organisms, mean zone of inhibition (mm). Tested bacteria
Gram reaction
Positive control (Amplicin)
M 1 (25 μg/mL)
M 2 (50 μg/mL)
Negative control
Klebsiella pneumoniae Pseudomonas aeruginosa E.coli Shigella flexneri Salmonella typhi Staphylococcus aureus Antibacterial index
−ve −ve −ve −ve −ve +ve
25 ± 20 ± 25 ± 25 ± 20 ± 20 ± 22.50
22 ± 0.1 18 ± 0.4 13 ± 0.6 10 ± 0.2 8 ± 0.4 12 ± 0.8 13.83
25 ± 20 ± 17 ± 20 ± 10 ± 17 ± 18.17
– – – – – –
0.2 0.8 0.7 0.6 0.4 0.8
II. The release of heavy metal ions I. Generation of ROS
Table 3 Comparison of anticancer activity for MCF-7 breast cancer cell line with reported values. Sample
IC50 (μg/mL)
Ref.
TiO2 CuO ZnO V2O5 CuO CuO Ta2O5
60.00 56.16 121.00 64.14 61.25 62.50 45.04
[50] [51] [52] [53] [54] [55] Present work
0.4 0.2 0.8 0.6 0.2 0.3
The photogeneration of ROS on the surface of the Ta2O5 nanoparticles depends on crystallite size, surface area, and oxygen vacancies. The average crystallite size of Ta2O5 obtained from XRD pattern (using Debye-Scherrer equation) found to be 30 nm. The surface defects were observed from the luminescence spectrum which indicates the emission at 535 nm. The ROS generation starts when the light irradiated on the cell culture with nanoparticles, which leads to the excitation of e− from VB to a new energy level CB leaving h+ in VB. 752
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
The %O2− radicals generate when the excited electron reacts with oxygen molecule and %O2H radical produced by the reaction of %O2− and H+ ions. The h+ react with H2O to produce •OH radicals and H+ ions reacts with %O2H to give hydrogen peroxide and it will damage the organic biomolecules including lipids, nucleic acids, proteins carbohydrates, DNA and amino acids. The biological effect of ROS (%OH, %O2− and %O2H) generation essentially depends on excited e−/h+ pairs energy level, the rate of generation and migration [44]. Bacteria + %OH → Bacterial inactivation (13)
NM/NS-1262/2013 (G) dated 18-03-2015). Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.microc.2019.03.094. References [1] Alok Mittal, Jyoti Mittal, Arti Malviya, V.K. Gupta, Removal and recovery of Chrysoidine Y from aqueous solutions by waste materials, J. Colloid Interface Sci. 344 (2010) 497. [2] Vinod Gupta, Rajeev Jain, Arunima Nayak, Shilpi Agarwal, Meenakshi Shrivastava, Removal of the hazardous dye—Tartrazine by photodegradation on titanium dioxide surface, Mater. Sci. Eng. C 31 (2011) 1062. [3] Anila Ajmal, Imran Majeed, Riffat Naseem Malik, Hicham Idriss, Muhammad Amtiaz Nadeem, RSC Adv. 4 (70) (2014) 37003. [4] K. Rajeshwar, M.E. Osugi, W. Chanmanee, C.R. Chenthamarakshan, M.V.B. Zanoni, P. Kajitvichyanukul, R. Krishnan-Ayer, J. Photochem. Photobiol. C: Photochem. Reviews 9 (4) (2008) 171. [5] U. Shanker, M. Rani, V. Jassal, Degradation of hazardous organic dyes in water by nanomaterials, Environ. Chem. Lett. 15 (4) (2017) 623. [6] Tawfik A. Saleh, Vinod K. Gupta, Photo-catalyzed degradation of hazardous dye methyl orange by use of a composite catalyst consisting of multi-walled carbon nanotubes and titanium dioxide, J. Colloid Interface Sci. 371 (2012) 101. [7] Saravanan Rajendran, Mohammad Mansoob Khan, F. Gracia, Jiaqian Qin, Vinod Kumar Gupta, Stephen Arumainathan, Ce3+-ion-induced visible-light photocatalytic degradatio electrochemical activity of ZnO/CeO2 nanocomposite, Sci. Rep. 6 (2016) 31641. [8] R. Saravanan, S. Karthikeyan, V.K. Gupta, G. Sekaran, V. Narayanan, A. Stephen, Enhanced photocatalytic activity of ZnO/CuO nanocomposite for the degradation of textile dye on visible light illumination, Mater. Sci. Eng. C 33 (2013) 91. [9] R. Saravanana, V.K. Gupta, T. Prakash, V. Narayana, A. Stephena, Synthesis, characterization and photocatalytic activity of novel hg doped ZnO nanorods prepared by thermal decomposition method, J. Mol. Liq. 178 (2013) 88. [10] Tawfik A. Saleh, Vinod K. Gupta, Functionalization of tungsten oxide into MWCNT and its application for sunlight-induced degradation of rhodamine B, J. Colloid Interface Sci. 362 (2011) 337. [11] R. Saravanan, S. Karthikeyan, V.K. Gupta, G. Sekaran, V. Narayanan, A. Stephen, Enhanced photocatalytic activity of ZnO/CuO nanocomposite for the degradation of textile dye on visible light illumination, Mater. Sci. Eng. C 33 (2013) 91–98. [12] R. Saravanan, M. Mansoob Khan, Vinod Kumar Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/CdO nanocomposite for visible light-induced photocatalytic degradation of industrial textile effluents, J. Colloid Interface Sci. 452 (2015) 126. [13] R. Saravanan, Mohammad Mansoob Khan, V.K. Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/Mn2O3 nanocomposite for visible light-induced industrial textile effluent degradation, uric acid and ascorbic acid sensing and antimicrobial activities, RSC Adv. 5 (2015) 34645. [14] R. Saravanan, E. Thirumal, V.K. Gupta, V. Narayanan, A. Stephen, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, J. Mol. Liq. 177 (2013) 394. [15] M. Ghaedi, S. Hajjati, Z. Mahmudi, I. Tyagi, Shilpi Agarwal, A. Maity, V.K. Gupta, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, Chem. Eng. J. 268 (2015) 28. [16] R. Saravanan, S. Joicy, V.K. Gupta, V. Narayanane, A. Stephen, Visible light induced degradation of methylene blue using CeO2/V2O5 and CeO2/CuO catalysts, Mater. Sci. Eng. C 33 (2013) 4725. [17] R. Saravanan, N. Karthikeyan, V.K. Gupt, E. Thirumal, P. Thangadurai, V. Narayanan, A. Stephen, ZnO/ag nanocomposite: an efficient catalyst for degradation studies of textile effluents under visible light, Mater. Sci. Eng. C 33 (2013) 2235. [18] R. Saravanan, M. Mansoob Khan, Vinod Kumar Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/CdO nanocomposite for visible light-induced photocatalytic degradation of industrial textile effluents, J. Colloid Interface Sci. 452 (2015) 126. [19] R. Saravanan, E. Thirumal, V.K. Gupta, V. Narayanan, A. Stephen, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, J. Mol. Liq. 177 (2013) 394. [20] Arash Asfaram, Mehrorang Ghaedi, Shilpi Agarwalb, Inderjeet Tyagib, Vinod Kumar Guptab, Removal of basic dye Auramine-O by ZnS: cu nanoparticles loaded on activated carbon optimization of parameters using response surface methodology with central composite design, RSC Adv. 5 (2015) 18438. [21] R. Saravanan, V.K. Gupta, V. Narayanan, A. Stephen, Visible light degradation of textile effluent using novel catalyst ZnO/g-Mn2O3, J. Taiwan Inst. Chem. Eng. 36 (2014) 1910. [22] R. Saravanan, Vinod Kumar Gupta, V. Narayanan, A. Stephen, Comparative study on photocatalytic activity of ZnO prepared by different methods, J. Mol. Liq. 181 (2013) 133. [23] R. Saravanan, V.K. Gupta, Edgar Mosquera, F. Gracia, Preparation and characterization of V2O5/ZnO nanocomposite system for photocatalytic application, J. Mol. Liq. 198 (2014) 409. [24] U. Shanker, M. Rani, V. Jassal, Degradation of hazardous organic dyes in water by
II. The release of heavy metal ions Ta2O5 interact with the cell membrane of bacteria and bind with the mesosome. The increase in the surface area of the bacterial cell membrane caused due to the disruption in the mesosome which acts on the cell division, DNA replication, and cellular respiration. Due to the cell expiry the ROS generation induced by the oxidative stress which changes the intracellular function (Fig. 5). When the heavy metal ions Ta5+ released by Ta2O5 nanoparticles the surface gets in connection with the microbe cell membranes. The positively charged Ta5+ mutually attracted by the negatively charged cell, and the thiol groups (eSH) with proteins forms when the metal ions penetrate into the cell membrane which confirms the presence of heavy metals on the surface of the bacterial cell (Fig. SI-5.). The nutrients transported by the protein which is entered through the cell membrane of bacteria. The death of the microbes caused by the decrease in the cell permeability and inactivation of proteins by the nanomaterials [45–47]. Table 2 shows the antimicrobial activity of Ta2O5 nanoparticles against bacterial pathogenic organisms, mean zone of inhibition (mm). The cytotoxicity of ultrasonic-assisted Ta2O5 nanoparticles has been estimated against MCF-7 cell lines with the different concentrations (5–320 μg/mL). It is examined that cell inhibition reduces at lesser concentrations of the Ta2O5 nanoparticles. Table Curve software has been used to analyze the IC50 values [48,49]. Ta2O5 nanoparticles confirm the activity of MCF-7 cancer cell line (IC50: 45.04 μg/mL). There is one probable mechanism occupied in the cancer cell death: (1) ROS take part in a vital function in the apoptosis cell death by Ta2O5 nanoparticles. Hydroxyl radical (oxidant) damage the single and double-strand DNA, identification of mutations and creation of oxidized nucleotides. Ta2O5 nanoparticles illustrate lesser IC50 evaluated with previous metal oxides nanomaterials (Table 3). Prepared ultrasoundmediated Ta2O5 nanoparticles (lower IC50) will be useful in pharmaceutical applications. 4. Conclusion Ta2O5 nanoparticles were obtained by the ultrasound-assisted method. XRD analysis confirms the orthorhombic structure. EDS spectrum gives the presence of elemental compositions of Ta and O in the obtained nanoparticles. TEM images show spherical shape of nanoparticles of size around 20 nm. The luminescence spectrum confirms the green emission of nanoparticles at maximum intensity of 535 nm. The prepared nanoparticles can be used in optical devices and high-quality monochromatic laser because of its luminescence properties. Ta2O5 nanoparticles exhibit superior photodegradation for methylene blue dye which is present in the textile industries using visible light and it has great impact in wastewater treatment. Ta2O5 nanoparticles enhanced the biological activities against the human pathogens and breast cancer cell line and useful in the pharmaceutical industries. Acknowledgement The authors immensely thank ISRO-RESPOND (Project No. ISRO/ RES/3/661/2014-15 Dated 14-07-2014) Govt. of India for sanctioning the project and financial assistance. The authors also thank DST Nanomission, Govt. of India, New Delhi for financial support. (No. SR/ 753
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al. nanomaterials, Environ. Chem. Lett. 15 (4) (2017) 623. [25] S.G. Kumar, K.K. Rao, Comparison of modification strategies towards enhanced charge carrier separation and photocatalytic degradation activity of metal oxide semiconductors (TiO2, WO3 and ZnO), Appl. Surf. Sci. 391 (2017) 124. [26] M. Vinuth, H.S.B. Naik, J. Manjanna, Remediation of hexavalent chromium from aqueous solution using clay mineral Fe(II)–montmorillonite: encompassing anion exclusion impact, Appl. Surf. Sci. 357 ( (2015) 1244. [27] K.N. Manukumar, Brij Kishore, K. Manjunath, G. Nagaraju, Mesoporous Ta2O5 nanoparticles as an anode material for lithium ion battery and an efficient photocatalyst for hydrogen evolution, Int. J. Hydrogy. Energy. 43 (2018) 18125. [28] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Andrographis paniculata extract mediated green synthesis of CdO nanoparticles and its electrochemical and antibacterial studies, J. Mater. Sci. Mater. Electron. 28 (2017) 7991. [29] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Nanostructured CdO-NiO composite for multifunctional applications, J. Phys. Chem. Solids 112 (2018) 106. [30] T. Mosmann, Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays, J. Immunol. Methods 65 (1983) 55. [31] H.X. Dang, Y.M. Lin, K.C. Klavetter, T.H. Cell, A. Heller, C.B. Mullins, Lithium insertion/Deinsertion characteristics of nanostructured amorphous tantalum oxide thin films, Chem. Electro. Chem. 1 (2014) 158. [32] Tran Van Khai, Tran Dai Lam, Van Thu Le, Hyoun Woo Kim, A two-step method for the preparation of highly conductive graphene film and its gas-sensing property, Mater. Sci. Appl. 6 (2015) 963. [33] S Mildred. Dresselhaus, Ado Jorio, Mario Hofmann, Gene Dresselhaus, Riichiro Saito, Perspectives on carbon nanotubes and graphene Raman spectroscopy, Nano Lett. 10 (3) (2010) 751. [34] Yue Wang, Yi-Jian Jiang, Composition dependence of dielectric properties of (Ta2O5)1−x(TiO2)x polycrystalline ceramics, Mater. Sci. Eng. B 99 (2003) 221. [35] T. Grewe, Tu ysu z H, Chem. Designing Photocatalysts for Hydrogen Evolution: Are Complex Preparation Strategies Necessary to Produce Active Catalysts Sus. Chem. 8 (2015) 3084. [36] S. Anandan, N. Pugazhenthiran, T. Selvamani, S.-H. Hsieh, G.-J. Lee, J.J. Wu, Investigation on photocatalytic potential of au–Ta2O5 semiconductor nanoparticle by degrading methyl Orange in aqueous solution by illuminating with visible light, Catal. Sci. Technol. 2 (2012) 2502. [37] M. Madhukara Naik, H.S. Bhojya Naik, G. Nagaraju, M. Vinuth, K. Vinu, S.K. Rashmi, Effect of aluminium doping on structural, optical, photocatalytic and antibacterial activity on nickel ferrite nanoparticles by sol–gel auto-combustion method, J. Mater. Sci. Mater. Electron. 29 (2018) 20395–20414. [38] M. Madhukara Naik, H.S. Bhojya Naik, G. Nagaraju, M. Vinuth, H. Raja Naika, K. Vinu, Green synthesis of zinc ferrite nanoparticles in Limonia acidissima juice: characterization and their application as photocatalytic and antibacterial activities, Microchem. J. (2018), https://doi.org/10.1016/j.microc.2019.02.059. [39] Rishu Katwal, Harpreet Kaur, Gaurav Sharma, Mu. Naushad, Deepak Pathania, Electrochemical synthesized copper oxide nanoparticles for enhanced photocatalytic and antimicrobial activity, J. Ind. Eng. Chem. 31 (2015) 173. [40] Sudhir S. Arbuj, Uttamrao P. Mulik, Dinesh P. Amalnerkar, Synthesis of Ta2O5/ TiO2 coupled semiconductor oxide nanocomposites with high photocatalytic activity, Nanosci. Nanotechnol. Lett. 5 (2013) 968. [41] Siddharth P. Deshpande, Mohaseen S. Tamboli, Sudhir S. Arbuj, Uttam P. Mulik, Dinesh P. Amalnerkar, Synthesis of nanostructured Ta2O5 and its photocatalytic performance study, J. Nanoeng. Nanomanuf. 4 (2014) 215.
[42] Yanhong Zhao, Lichun Hai, Xiang Li, Xiadong Yang, Xiaojing Wang, Photocatalytic activity of W doped Ta2O5 particles for methylene blue, degradation under UVlight, Adv. Mater. Res. 197-198 (2011) 281. [43] Lalitha Gnanasekran, R. Hemamalini, R. Saravanan, K. Ravichandran, F. Gracia, Shilpi Agarwal, Vinod Kumar Gupta, Synthesis and characterization of metal oxides (CeO2, CuO, NiO, Mn3O4, SnO2 and ZnO) nanoparticles as photo catalysts for degradation of textile dyes, J. Photochem. Photobiol. B Biol. 173 (2017) 43. [44] Neena Prasad, Karthikeyan Balasubramanian, Optical, phonon and efficient visible and infrared photocatalytic activity of cu doped ZnS micro crystals, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 173 (2017) 687. [45] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Multifunctional properties of CdO nanostructures synthesised through microwave assisted hydrothermal method, Mater. Res. Innov. DOI:https://doi.org/10.1080/ 14328917.2018.1475443. [46] S. Kaviya, J. Santhanalakshmi, B. Viswanathan, J. Muthumary, K. Srinivasan, Biosynthesis of silver nanoparticles using citrus sinensis peel extract and its antibacterial activity, Spectrochim. Acta Part. A 79 (2011) 594. [47] Mohammed A. Al-Omair, Mai M. Khalafa, A.H. Touny, H. Elsawy, M.M. Saleh, Antimicrobial activities of mesoporous nickel phosphate synthesized with lowtemperature method, Microchem. J. 145 (2019) 113. [48] Manikandan Ramar, Beulaja Manikandan, Prabhu Narayanan Marimuthu, Thiyagarajan Ramar, Anjugam Mahalingam, Palanisamy Subramanian, Saravanan Karthick, Arumugam Munusamy, Synthesis of silver nanoparticles using Solanum trilobatum fruits extract and its antibacterial, cytotoxic activity against human breast cancer cell line MCF 7, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 140 (2015) 223. [49] Govindasamy Sharmila, Marimuthu Thirumarimurugan, Chandrasekaran Muthukumaran, Green synthesis of ZnO nanoparticles using Tecoma castanifolia leaf extract: characterization and evaluation of its antioxidant, bactericidal and anticancer activities, Microchem. J. 145 (2019) 578. [50] Kadarkarai Murugan, Devakumar Dinesh, Krishnamoorthy Kavithaa, Manickam Paulpandi, Thondhi Ponraj, Mohamad Saleh Alsalhi, Sandhanasamy Devanesan, Jayapal Subramaniam, Rajapandian Rajaganesh, Hui Wei, Suresh Kumar, Marcello Nicoletti, Giovanni Benelli, Hydrothermal synthesis of titanium dioxide nanoparticles: mosquitocidal potential and anticancer activity on human breast cancer cells (MCF-7), Parasitol. Res. 115 (2016) 1085. [51] R. Sivaraj, P.K. Rahman, P. Rajiv, S. Narendhran, R. Venckatesh, Biosynthesis and characterization of Acalypha indica mediated copper oxide nanoparticles and evaluation of its antimicrobial and anticancer activity, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 129 (17) (2014) 255. [52] Amin Boroumand Moghaddam, Mona Moniri, Susan Azizi, Raha Abdul Rahim, Arbakariya Bin Ariff, Mohammad Navaderi, Rosfarizan Mohamad, Eco-friendly formulated zinc oxide nanoparticles: induction of Cell cycle arrest and apoptosis in the MCF-7 Cancer Cell line, Genes 8 (2017) 281. [53] Ebru Özturk, Ayşe Kübra Karaboga Arslan, Alim Hüseyin Dokumaci, Mükerrem Betül Yerer, Turk. Real-time analysis of impedance alterations by the effects of vanadium pentoxide on several carcinoma Cell lines, J. Pharm. Sci. 15 (1) (2018) 1. [54] Sri Vishnu Priya Ramaswamy, S. Narendhran, Rajeshwari Sivaraj, Potentiating effect of ecofriendly synthesis of copper oxide nanoparticles using brown alga: antimicrobial and anticancer activities, Bull. Mater. Sci. 39 (2) (2016) 361. [55] J. Emima Jeronsia, D.J. Vidhya Raj, L. Allwin Joseph, K. Rubini, S. Jerome Das, In vitro antibacterial and anticancer activity of copper oxide nanostructures in human breast cancer Michigan Cancer Foundation-7 cells, J. Med. Sci. 36 (4) (2016) 145.
754
Contents lists available at ScienceDirect
Microchemical Journal journal homepage: www.elsevier.com/locate/microc
Ultrasound-assisted Ta2O5 nanoparticles and their photocatalytic and biological applications
T
G. Nagaraju , K. Karthik, M. Shashank ⁎
Energy Materials Research Laboratory, Department of Chemistry, Siddaganga Institute of Technology, Tumakuru 572 103, India
ARTICLE INFO
ABSTRACT
Keywords: Ta2O5 nanoparticles Ultrasound-assisted synthesis Photocatalytic activity Antibacterial Anticancer studies
Ta2O5 nanoparticles were synthesized by ultrasound-assisted method. The prepared nanoparticles were characterized structurally by XRD, Raman and morphologically by SEM and TEM. From the XRD pattern, orthorhombic phase Ta2O5 was observed. Raman studies confirm the presence of TaeO at 613 cm−1. TEM images show the average particle size of about 21 nm. Band gap of Ta2O5 nanoparticles were carried out by UV-DRS and found to be 3.12 eV. Photocatalytic activity of Ta2O5 nanoparticles have been examined for the degradation of methylene blue dye and shows 96% degradation after 2 h under visible light irradiation. Ta2O5 nanoparticles also exhibited good antibacterial activity against the foodborne pathogens and anti-breast cancer (MCF-7: IC50: 45.04 μg/mL) activity.
1. Introduction Dyes are the dominant pollutants in the aquatic environment which are toxic and hazardous to many organisms because of decoloration, slow biological degradation, and high chemical oxygen demand [1,2]. In industries, nearly 1,00,000 different types of commercially available dyes have been using used most frequently. Around 15% of the dyes produces annually more than 70,000 tons which are mainly derived from coal tar and petroleum intermediates and are discharged into water bodies without any treatment [3]. The textile, paper, plastic, leather tanning, food, and cosmetic industries are the major cause of the production of waste in water including electrochemical cells and light reaping arrays. Synthetic dyes (azo dyes) acquire large group as colorants (~50–70%) and in industries, 50% of azo dyes were used. Anthraquinone dyes are following next to azo dyes [4,5]. Semiconductor photocatalyst and their heterostructures have been extensively used for decontamination of water caused by various industries under light radiations [6–23]. From past few years, several physical, chemical, and biological methods were adopted for wastewater treatment including reverse osmosis, adsorption, ultrafiltration, coagulation-flocculation, chlorination, ozonation, and biodegradation (microbial) etc. [24,25]. Though, some of these methods cause secondary pollution by transferring organic pollutant from wastewater to another phase. Except for these methods, photocatalytic processes appear as the most promising and widely used technology for the purification of contaminants (organic pollutants) under ambient conditions
⁎
using solar radiation as a source of energy. This is an environmentally friendly method which utilizes radiation as energy. Nevertheless, using metal oxide nanoparticles application of the photocatalytic process is limited to few studies for the remediation of wastewater [26]. Several metal oxide nanoparticles suggest superior photocatalytic, antibacterial, and anticancer performance towards the organic dye degradation, human pathogenic bacteria and cancer cell lines. Metal oxide nanoparticles are widely used because of a simple and less tedious experimental procedure and also non-toxic. Ta2O5 has extensive applications such as optoelectronics, sensors, battery and biological activities. Ta2O5 is a p-type semiconductor (3.8–5.3 eV) with cubic structure. Ta2O5 nanomaterials broadly studied because of its large dielectric and electrochemical properties [27]. This article reports the novel synthesis of Ta2O5 nanoparticles via ultrasonication method at lab temperature without using any surfactant. The structurally characterized and optically studied calcined Ta2O5 nanoparticle materials were examined for various applications including photocatalytic activity, antibacterial activity and anticancer applications. 2. Experimental 2.1. Preparation of Ta2O5 0.5 g TaCl5 was dispersed in 20 mL absolute ethanol and stirred for 1 h. Then 1 mL of double distilled water was added to the above
Corresponding author. E-mail address: [email protected] (G. Nagaraju).
https://doi.org/10.1016/j.microc.2019.03.094 Received 3 December 2018; Received in revised form 12 March 2019; Accepted 29 March 2019 Available online 30 March 2019 0026-265X/ © 2019 Published by Elsevier B.V.
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
solution. Further, the mixed solution was exposed to high-intensity ultrasonic irradiation (frequency: 40 kHz and power: 50 W) (Digital Ultrasonic Cleaner LUMC-2) for 60 min. The precipitate was centrifuged and washed with distilled water and ethanol several times. The sample was dried under vacuum at 70 °C for about 6 h. The obtained powder was calcinated at 800 °C for 2 h. 2.2. Characterization Ultrasound-assisted Ta2O5 nanoparticles was identified using Smart lab X-ray diffractometer (CuKα, λ = 1.5406 Å). The molecular structure was confirmed by Peak Seeker Raman Spectrometer. The surface morphology was examined by SEM (VEGA 3 TESCAN SEM). Particle sizes and crystalline nature were studied by HRTEM (JEOL/JEM 2100). 2.3. Photocatalytic activity setup The photodegradation activity of the Ta2O5 nanoparticles was carried out by measuring the degradation of Methylene blue (MB) dye in aqueous solution under visible light. In photocatalytic degradation experiment, 100 mL of known concentration of methylene blue was taken in glass tube followed by the addition of known quantity of Ta2O5 photocatalyst. During visible light irradiation, at an interval of 30 min the aqueous sample was collected from the reaction mixture and centrifuged to remove the catalyst. UV–Vis absorption spectrophotometer was used to observe the decrease in the absorbance with degradation of MB dyes at 664 nm (λmax). The dye degradation percentage was calculated by using the following relation
=
C0
Ct C0
× 100
Fig. 1. XRD pattern of ultrasound-assisted Ta2O5 nanoparticles.
having the size of ~20 nm. HRTEM (Fig. 2c) images exhibits the interlayer spacing of 2.3 Å which demonstrates the growing direction along (1111). SAED pattern (Fig. 2d) suggests the good crystallinity of the prepared materials. The optical properties of Ta2O5 nanoparticles (Fig. SI-3a) were studied using UV–Visible diffused reflectance spectroscopy (UV-DRS). Using Kubelka-Munk relation the energy band gap was approximately calculated from optical reflectance values. A graph of [F(R)]2 vs. hυ plotted and the obtained intercept gives the bandgap energy. The Kubelka-Munk relation is given below
(1)
F (R ) =
Here, η is the degradation percentage, C0 is the initial absorbance of dye (mg/L); Ct is the change in absorbance of the dye at selected intervals of the degradation (mg/L).
(1
R)2 2R
(2)
Fig. SI-3b gives the projected optical energy band gap of Ta2O5 nanoparticles and was found to be 3.12 eV which is lower when compared with the reported value for the bulk Ta2O5 (3.8 eV) [35]. Room temperature photoluminescence spectrum of Ta2O5 nanoparticles was performed and the result is shown in Fig. SI-4. The peak at 325 nm corresponds to the UV emission. The emission peaks at 444 and 482 nm are originated from the irradiative recombination of free electrons. The peak at 535 nm is assigned to the green emission [36]. Photocatalytic activity of Ta2O5 nanoparticles was assessed by degradation of methylene blue (MB) dye as a targeted pollutant beneath visible light radiations. During the degradation process, absorption maxima gradually decreased in the presence of Ta2O5 nanoparticles at different interval of time at λmax = 664 nm (Fig. 3). In dark there is no degradation was observed for MB and also in the absence of the catalyst; MB exhibits trivial self-degradation (3%) under visible light illumination. The photocatalytic activity was enhanced gradually to 96% in 120 min. The kinetics performance of Ta2O5 nanoparticles for the degradation of MB was performed. Langmuir-Hinshelwood model (Eq. (3)) was used to understand the photodegradation kinetics of MB, this model describes rate constant of photodegradation of the MB.
2.4. Antibacterial activity assay The antibacterial study was carried out using the same procedure (disc diffusion method) published in the previous paper [28]. 2.5. Anticancer activity assay Procedure for the anti-breast cancer activity of Ta2O5 nanoparticles is referred to the articles published by Karthik et al. and Mosmann et al. [29,30]. 3. Results and discussion 3.1. Structural and morphological studies Fig. 1 represents the X-ray diffraction pattern of the prepared Ta2O5 nanoparticles calcined at 800 °C. All the diffraction peaks match well with the characteristic reflections. Formation of the orthorhombic structure with sharp peaks and planes were observed, which indicates the p2mm space group symmetry with the formation of a single phase (JCPDS Card No. 25-0922) without any secondary phase. The average crystallite size (D) was calculated using the Debye-Scherrer equation [31] and found to be ~30 nm. k D = Cos Raman studies of Ta2O5 nanoparticles are shown in Fig. SI-1. Raman peaks at 251, 613 and 840 cm−1 are corresponding to the OeTaeO bending vibrations in TaO6 octahedra and symmetric stretching of the various TaeO bonds [32–34]. SEM images (Fig. SI-2a) shown that particles are agglomerated. EDS spectrum validates the occurrence of Ta and O (Fig. – SI 2b). TEM images (Fig. 2a,b) clearly shows the presence of almost spherical shape
(3)
ln(C 0 / C t) = Kt
where C0 is the initial absorbance of MB dye at time t = 0, Ct is the change in absorbance of MB dye at selected intervals of degradation, and k is the first order rate constant. The photocatalytic activity of Ta2O5 nanoparticles with k value is 1.16 × 10−2 min−1. 3.2. Photodegradation mechanism Degradation mechanism of dye solution was stated in the following equations.
Ta2O5 + h (Vis) 750
Ta2O5 (e
CB
+ h+ VB)
(4)
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
Fig. 2. (a & b) TEM images, (c) HRTEM images and (d) SAED pattern of Ta2O5 nanoparticles.
recombination of e−/h+ pairs and takes part in the oxidation process; hence, it maintains the electron neutrality in Ta2O5. The protonation of %O2− gives hydroperoxyl radicals and forms hydrogen peroxide (H2O2), then %OH radicals will be produced after the dissociation of H2O2 (Eq. (6)–(8)). The organic molecules attacked by the reactive species produced on the surface of the Ta2O5 nanoparticles which act as a strong oxidizing agent [37,38]. The mineralization of organic molecules occurs when these reactive species attack them and forms carbon dioxide and the water molecule (Eq. (10)). Table 1 shows the photocatalytic degradation efficiency of ultrasound-assisted Ta2O5 nanoparticles for (MB dye) is compared with reported values. Table 1 summarizes the Photocatalytic activities of the methylene blue dye using various transition metal oxide nanoparticles. The antibacterial activity of ultrasound-assisted Ta2O5 nanoparticles were performed against gram-positive (S. aureus) gram-negative (E. coli, P. aeruginosa, K. pneumoniae, S. flexneri and S. typhi) bacterial strains (Fig. 4). The most significant antibacterial effect of nanoparticles was found for the concentration of 50 μg/mL per disc against K. pneumoniae to produce inhibition zone of 25 mm. The efficiency of the antibacterial activity of prepared nanomaterials mainly depends on the following factors viz.
Fig. 3. Photocatalytic absorbance spectrum of Ta2O5 nanoparticles.
Ta2O5 (e
CB)
+ O2
H2 O2
(5)
HOO
(6)
H2 O2 + O2
(7)
O2 + H+ 2HOO
O2
HO + H+
Ta2O5 + H2 O
Dye + HO + O2 Dye + Ta2O5
CO2 + H2 O (Byproduct)
Table 1 Photocatalytic degradation efficiency (MB dye) of ultrasound-assisted Ta2O5 nanoparticles compared with reported values.
(9) (10)
VB)
Oxidation product
(11)
Sample
Degradation efficiency (%)
Reference
CB)
Reduction product
(12)
Ta2O5 Ta2O5 W-Ta2O5 CeO2 CuO NiO Mn3O4 SnO2 ZnS Cu doped ZnS Ta2O5
39 23 91 77 15 55 26 83 23 73.5 96
[39] [40] [41] [42] [42] [42] [42] [42] [43] [43] Present work
(h+
Dye + Ta2O5 (e
I. Production of reactive oxygen species (ROS)
(8)
2HO
The photodegradation originates when the visible light irradiated on the Ta2O5 photocatalyst, which leads to the excitation of electrons from VB to a new energy level CB leaving holes in VB (Eq. (4)). In the VB same amount of holes produced simultaneously which react with the water surface or hydroxyl ion to produce hydroxyl radicals (%OH). Simultaneously superoxide radicals (%O2−) through reduction produced when the dissolved oxygen molecules reacts with the electrons in the CB on the surface of the NPs (Eq. (5)). This radical avoids the 751
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
Fig. 4. Antibacterial activity of Ta2O5 nanoparticles against food borne pathogens (M1: 25 μg/mL and M2: 50 μg/mL).
Fig. 5. Cytotoxicity of ultrasound-assisted Ta2O5 nanoparticles against human breast cancer cell line MCF-7. Table 2 Antimicrobial activity of ultrasound-assisted Ta2O5 nanoparticles against bacterial pathogenic organisms, mean zone of inhibition (mm). Tested bacteria
Gram reaction
Positive control (Amplicin)
M 1 (25 μg/mL)
M 2 (50 μg/mL)
Negative control
Klebsiella pneumoniae Pseudomonas aeruginosa E.coli Shigella flexneri Salmonella typhi Staphylococcus aureus Antibacterial index
−ve −ve −ve −ve −ve +ve
25 ± 20 ± 25 ± 25 ± 20 ± 20 ± 22.50
22 ± 0.1 18 ± 0.4 13 ± 0.6 10 ± 0.2 8 ± 0.4 12 ± 0.8 13.83
25 ± 20 ± 17 ± 20 ± 10 ± 17 ± 18.17
– – – – – –
0.2 0.8 0.7 0.6 0.4 0.8
II. The release of heavy metal ions I. Generation of ROS
Table 3 Comparison of anticancer activity for MCF-7 breast cancer cell line with reported values. Sample
IC50 (μg/mL)
Ref.
TiO2 CuO ZnO V2O5 CuO CuO Ta2O5
60.00 56.16 121.00 64.14 61.25 62.50 45.04
[50] [51] [52] [53] [54] [55] Present work
0.4 0.2 0.8 0.6 0.2 0.3
The photogeneration of ROS on the surface of the Ta2O5 nanoparticles depends on crystallite size, surface area, and oxygen vacancies. The average crystallite size of Ta2O5 obtained from XRD pattern (using Debye-Scherrer equation) found to be 30 nm. The surface defects were observed from the luminescence spectrum which indicates the emission at 535 nm. The ROS generation starts when the light irradiated on the cell culture with nanoparticles, which leads to the excitation of e− from VB to a new energy level CB leaving h+ in VB. 752
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al.
The %O2− radicals generate when the excited electron reacts with oxygen molecule and %O2H radical produced by the reaction of %O2− and H+ ions. The h+ react with H2O to produce •OH radicals and H+ ions reacts with %O2H to give hydrogen peroxide and it will damage the organic biomolecules including lipids, nucleic acids, proteins carbohydrates, DNA and amino acids. The biological effect of ROS (%OH, %O2− and %O2H) generation essentially depends on excited e−/h+ pairs energy level, the rate of generation and migration [44]. Bacteria + %OH → Bacterial inactivation (13)
NM/NS-1262/2013 (G) dated 18-03-2015). Appendix A. Supplementary data Supplementary data to this article can be found online at https:// doi.org/10.1016/j.microc.2019.03.094. References [1] Alok Mittal, Jyoti Mittal, Arti Malviya, V.K. Gupta, Removal and recovery of Chrysoidine Y from aqueous solutions by waste materials, J. Colloid Interface Sci. 344 (2010) 497. [2] Vinod Gupta, Rajeev Jain, Arunima Nayak, Shilpi Agarwal, Meenakshi Shrivastava, Removal of the hazardous dye—Tartrazine by photodegradation on titanium dioxide surface, Mater. Sci. Eng. C 31 (2011) 1062. [3] Anila Ajmal, Imran Majeed, Riffat Naseem Malik, Hicham Idriss, Muhammad Amtiaz Nadeem, RSC Adv. 4 (70) (2014) 37003. [4] K. Rajeshwar, M.E. Osugi, W. Chanmanee, C.R. Chenthamarakshan, M.V.B. Zanoni, P. Kajitvichyanukul, R. Krishnan-Ayer, J. Photochem. Photobiol. C: Photochem. Reviews 9 (4) (2008) 171. [5] U. Shanker, M. Rani, V. Jassal, Degradation of hazardous organic dyes in water by nanomaterials, Environ. Chem. Lett. 15 (4) (2017) 623. [6] Tawfik A. Saleh, Vinod K. Gupta, Photo-catalyzed degradation of hazardous dye methyl orange by use of a composite catalyst consisting of multi-walled carbon nanotubes and titanium dioxide, J. Colloid Interface Sci. 371 (2012) 101. [7] Saravanan Rajendran, Mohammad Mansoob Khan, F. Gracia, Jiaqian Qin, Vinod Kumar Gupta, Stephen Arumainathan, Ce3+-ion-induced visible-light photocatalytic degradatio electrochemical activity of ZnO/CeO2 nanocomposite, Sci. Rep. 6 (2016) 31641. [8] R. Saravanan, S. Karthikeyan, V.K. Gupta, G. Sekaran, V. Narayanan, A. Stephen, Enhanced photocatalytic activity of ZnO/CuO nanocomposite for the degradation of textile dye on visible light illumination, Mater. Sci. Eng. C 33 (2013) 91. [9] R. Saravanana, V.K. Gupta, T. Prakash, V. Narayana, A. Stephena, Synthesis, characterization and photocatalytic activity of novel hg doped ZnO nanorods prepared by thermal decomposition method, J. Mol. Liq. 178 (2013) 88. [10] Tawfik A. Saleh, Vinod K. Gupta, Functionalization of tungsten oxide into MWCNT and its application for sunlight-induced degradation of rhodamine B, J. Colloid Interface Sci. 362 (2011) 337. [11] R. Saravanan, S. Karthikeyan, V.K. Gupta, G. Sekaran, V. Narayanan, A. Stephen, Enhanced photocatalytic activity of ZnO/CuO nanocomposite for the degradation of textile dye on visible light illumination, Mater. Sci. Eng. C 33 (2013) 91–98. [12] R. Saravanan, M. Mansoob Khan, Vinod Kumar Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/CdO nanocomposite for visible light-induced photocatalytic degradation of industrial textile effluents, J. Colloid Interface Sci. 452 (2015) 126. [13] R. Saravanan, Mohammad Mansoob Khan, V.K. Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/Mn2O3 nanocomposite for visible light-induced industrial textile effluent degradation, uric acid and ascorbic acid sensing and antimicrobial activities, RSC Adv. 5 (2015) 34645. [14] R. Saravanan, E. Thirumal, V.K. Gupta, V. Narayanan, A. Stephen, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, J. Mol. Liq. 177 (2013) 394. [15] M. Ghaedi, S. Hajjati, Z. Mahmudi, I. Tyagi, Shilpi Agarwal, A. Maity, V.K. Gupta, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, Chem. Eng. J. 268 (2015) 28. [16] R. Saravanan, S. Joicy, V.K. Gupta, V. Narayanane, A. Stephen, Visible light induced degradation of methylene blue using CeO2/V2O5 and CeO2/CuO catalysts, Mater. Sci. Eng. C 33 (2013) 4725. [17] R. Saravanan, N. Karthikeyan, V.K. Gupt, E. Thirumal, P. Thangadurai, V. Narayanan, A. Stephen, ZnO/ag nanocomposite: an efficient catalyst for degradation studies of textile effluents under visible light, Mater. Sci. Eng. C 33 (2013) 2235. [18] R. Saravanan, M. Mansoob Khan, Vinod Kumar Gupta, E. Mosquera, F. Gracia, V. Narayanan, A. Stephen, ZnO/ag/CdO nanocomposite for visible light-induced photocatalytic degradation of industrial textile effluents, J. Colloid Interface Sci. 452 (2015) 126. [19] R. Saravanan, E. Thirumal, V.K. Gupta, V. Narayanan, A. Stephen, The photocatalytic activity of ZnO prepared by simple thermal decomposition method at various temperatures, J. Mol. Liq. 177 (2013) 394. [20] Arash Asfaram, Mehrorang Ghaedi, Shilpi Agarwalb, Inderjeet Tyagib, Vinod Kumar Guptab, Removal of basic dye Auramine-O by ZnS: cu nanoparticles loaded on activated carbon optimization of parameters using response surface methodology with central composite design, RSC Adv. 5 (2015) 18438. [21] R. Saravanan, V.K. Gupta, V. Narayanan, A. Stephen, Visible light degradation of textile effluent using novel catalyst ZnO/g-Mn2O3, J. Taiwan Inst. Chem. Eng. 36 (2014) 1910. [22] R. Saravanan, Vinod Kumar Gupta, V. Narayanan, A. Stephen, Comparative study on photocatalytic activity of ZnO prepared by different methods, J. Mol. Liq. 181 (2013) 133. [23] R. Saravanan, V.K. Gupta, Edgar Mosquera, F. Gracia, Preparation and characterization of V2O5/ZnO nanocomposite system for photocatalytic application, J. Mol. Liq. 198 (2014) 409. [24] U. Shanker, M. Rani, V. Jassal, Degradation of hazardous organic dyes in water by
II. The release of heavy metal ions Ta2O5 interact with the cell membrane of bacteria and bind with the mesosome. The increase in the surface area of the bacterial cell membrane caused due to the disruption in the mesosome which acts on the cell division, DNA replication, and cellular respiration. Due to the cell expiry the ROS generation induced by the oxidative stress which changes the intracellular function (Fig. 5). When the heavy metal ions Ta5+ released by Ta2O5 nanoparticles the surface gets in connection with the microbe cell membranes. The positively charged Ta5+ mutually attracted by the negatively charged cell, and the thiol groups (eSH) with proteins forms when the metal ions penetrate into the cell membrane which confirms the presence of heavy metals on the surface of the bacterial cell (Fig. SI-5.). The nutrients transported by the protein which is entered through the cell membrane of bacteria. The death of the microbes caused by the decrease in the cell permeability and inactivation of proteins by the nanomaterials [45–47]. Table 2 shows the antimicrobial activity of Ta2O5 nanoparticles against bacterial pathogenic organisms, mean zone of inhibition (mm). The cytotoxicity of ultrasonic-assisted Ta2O5 nanoparticles has been estimated against MCF-7 cell lines with the different concentrations (5–320 μg/mL). It is examined that cell inhibition reduces at lesser concentrations of the Ta2O5 nanoparticles. Table Curve software has been used to analyze the IC50 values [48,49]. Ta2O5 nanoparticles confirm the activity of MCF-7 cancer cell line (IC50: 45.04 μg/mL). There is one probable mechanism occupied in the cancer cell death: (1) ROS take part in a vital function in the apoptosis cell death by Ta2O5 nanoparticles. Hydroxyl radical (oxidant) damage the single and double-strand DNA, identification of mutations and creation of oxidized nucleotides. Ta2O5 nanoparticles illustrate lesser IC50 evaluated with previous metal oxides nanomaterials (Table 3). Prepared ultrasoundmediated Ta2O5 nanoparticles (lower IC50) will be useful in pharmaceutical applications. 4. Conclusion Ta2O5 nanoparticles were obtained by the ultrasound-assisted method. XRD analysis confirms the orthorhombic structure. EDS spectrum gives the presence of elemental compositions of Ta and O in the obtained nanoparticles. TEM images show spherical shape of nanoparticles of size around 20 nm. The luminescence spectrum confirms the green emission of nanoparticles at maximum intensity of 535 nm. The prepared nanoparticles can be used in optical devices and high-quality monochromatic laser because of its luminescence properties. Ta2O5 nanoparticles exhibit superior photodegradation for methylene blue dye which is present in the textile industries using visible light and it has great impact in wastewater treatment. Ta2O5 nanoparticles enhanced the biological activities against the human pathogens and breast cancer cell line and useful in the pharmaceutical industries. Acknowledgement The authors immensely thank ISRO-RESPOND (Project No. ISRO/ RES/3/661/2014-15 Dated 14-07-2014) Govt. of India for sanctioning the project and financial assistance. The authors also thank DST Nanomission, Govt. of India, New Delhi for financial support. (No. SR/ 753
Microchemical Journal 147 (2019) 749–754
G. Nagaraju, et al. nanomaterials, Environ. Chem. Lett. 15 (4) (2017) 623. [25] S.G. Kumar, K.K. Rao, Comparison of modification strategies towards enhanced charge carrier separation and photocatalytic degradation activity of metal oxide semiconductors (TiO2, WO3 and ZnO), Appl. Surf. Sci. 391 (2017) 124. [26] M. Vinuth, H.S.B. Naik, J. Manjanna, Remediation of hexavalent chromium from aqueous solution using clay mineral Fe(II)–montmorillonite: encompassing anion exclusion impact, Appl. Surf. Sci. 357 ( (2015) 1244. [27] K.N. Manukumar, Brij Kishore, K. Manjunath, G. Nagaraju, Mesoporous Ta2O5 nanoparticles as an anode material for lithium ion battery and an efficient photocatalyst for hydrogen evolution, Int. J. Hydrogy. Energy. 43 (2018) 18125. [28] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Andrographis paniculata extract mediated green synthesis of CdO nanoparticles and its electrochemical and antibacterial studies, J. Mater. Sci. Mater. Electron. 28 (2017) 7991. [29] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Nanostructured CdO-NiO composite for multifunctional applications, J. Phys. Chem. Solids 112 (2018) 106. [30] T. Mosmann, Rapid colorimetric assay for cellular growth and survival: application to proliferation and cytotoxicity assays, J. Immunol. Methods 65 (1983) 55. [31] H.X. Dang, Y.M. Lin, K.C. Klavetter, T.H. Cell, A. Heller, C.B. Mullins, Lithium insertion/Deinsertion characteristics of nanostructured amorphous tantalum oxide thin films, Chem. Electro. Chem. 1 (2014) 158. [32] Tran Van Khai, Tran Dai Lam, Van Thu Le, Hyoun Woo Kim, A two-step method for the preparation of highly conductive graphene film and its gas-sensing property, Mater. Sci. Appl. 6 (2015) 963. [33] S Mildred. Dresselhaus, Ado Jorio, Mario Hofmann, Gene Dresselhaus, Riichiro Saito, Perspectives on carbon nanotubes and graphene Raman spectroscopy, Nano Lett. 10 (3) (2010) 751. [34] Yue Wang, Yi-Jian Jiang, Composition dependence of dielectric properties of (Ta2O5)1−x(TiO2)x polycrystalline ceramics, Mater. Sci. Eng. B 99 (2003) 221. [35] T. Grewe, Tu ysu z H, Chem. Designing Photocatalysts for Hydrogen Evolution: Are Complex Preparation Strategies Necessary to Produce Active Catalysts Sus. Chem. 8 (2015) 3084. [36] S. Anandan, N. Pugazhenthiran, T. Selvamani, S.-H. Hsieh, G.-J. Lee, J.J. Wu, Investigation on photocatalytic potential of au–Ta2O5 semiconductor nanoparticle by degrading methyl Orange in aqueous solution by illuminating with visible light, Catal. Sci. Technol. 2 (2012) 2502. [37] M. Madhukara Naik, H.S. Bhojya Naik, G. Nagaraju, M. Vinuth, K. Vinu, S.K. Rashmi, Effect of aluminium doping on structural, optical, photocatalytic and antibacterial activity on nickel ferrite nanoparticles by sol–gel auto-combustion method, J. Mater. Sci. Mater. Electron. 29 (2018) 20395–20414. [38] M. Madhukara Naik, H.S. Bhojya Naik, G. Nagaraju, M. Vinuth, H. Raja Naika, K. Vinu, Green synthesis of zinc ferrite nanoparticles in Limonia acidissima juice: characterization and their application as photocatalytic and antibacterial activities, Microchem. J. (2018), https://doi.org/10.1016/j.microc.2019.02.059. [39] Rishu Katwal, Harpreet Kaur, Gaurav Sharma, Mu. Naushad, Deepak Pathania, Electrochemical synthesized copper oxide nanoparticles for enhanced photocatalytic and antimicrobial activity, J. Ind. Eng. Chem. 31 (2015) 173. [40] Sudhir S. Arbuj, Uttamrao P. Mulik, Dinesh P. Amalnerkar, Synthesis of Ta2O5/ TiO2 coupled semiconductor oxide nanocomposites with high photocatalytic activity, Nanosci. Nanotechnol. Lett. 5 (2013) 968. [41] Siddharth P. Deshpande, Mohaseen S. Tamboli, Sudhir S. Arbuj, Uttam P. Mulik, Dinesh P. Amalnerkar, Synthesis of nanostructured Ta2O5 and its photocatalytic performance study, J. Nanoeng. Nanomanuf. 4 (2014) 215.
[42] Yanhong Zhao, Lichun Hai, Xiang Li, Xiadong Yang, Xiaojing Wang, Photocatalytic activity of W doped Ta2O5 particles for methylene blue, degradation under UVlight, Adv. Mater. Res. 197-198 (2011) 281. [43] Lalitha Gnanasekran, R. Hemamalini, R. Saravanan, K. Ravichandran, F. Gracia, Shilpi Agarwal, Vinod Kumar Gupta, Synthesis and characterization of metal oxides (CeO2, CuO, NiO, Mn3O4, SnO2 and ZnO) nanoparticles as photo catalysts for degradation of textile dyes, J. Photochem. Photobiol. B Biol. 173 (2017) 43. [44] Neena Prasad, Karthikeyan Balasubramanian, Optical, phonon and efficient visible and infrared photocatalytic activity of cu doped ZnS micro crystals, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 173 (2017) 687. [45] K. Karthik, S. Dhanuskodi, C. Gobinath, S. Prabukumar, S. Sivaramakrishnan, Multifunctional properties of CdO nanostructures synthesised through microwave assisted hydrothermal method, Mater. Res. Innov. DOI:https://doi.org/10.1080/ 14328917.2018.1475443. [46] S. Kaviya, J. Santhanalakshmi, B. Viswanathan, J. Muthumary, K. Srinivasan, Biosynthesis of silver nanoparticles using citrus sinensis peel extract and its antibacterial activity, Spectrochim. Acta Part. A 79 (2011) 594. [47] Mohammed A. Al-Omair, Mai M. Khalafa, A.H. Touny, H. Elsawy, M.M. Saleh, Antimicrobial activities of mesoporous nickel phosphate synthesized with lowtemperature method, Microchem. J. 145 (2019) 113. [48] Manikandan Ramar, Beulaja Manikandan, Prabhu Narayanan Marimuthu, Thiyagarajan Ramar, Anjugam Mahalingam, Palanisamy Subramanian, Saravanan Karthick, Arumugam Munusamy, Synthesis of silver nanoparticles using Solanum trilobatum fruits extract and its antibacterial, cytotoxic activity against human breast cancer cell line MCF 7, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 140 (2015) 223. [49] Govindasamy Sharmila, Marimuthu Thirumarimurugan, Chandrasekaran Muthukumaran, Green synthesis of ZnO nanoparticles using Tecoma castanifolia leaf extract: characterization and evaluation of its antioxidant, bactericidal and anticancer activities, Microchem. J. 145 (2019) 578. [50] Kadarkarai Murugan, Devakumar Dinesh, Krishnamoorthy Kavithaa, Manickam Paulpandi, Thondhi Ponraj, Mohamad Saleh Alsalhi, Sandhanasamy Devanesan, Jayapal Subramaniam, Rajapandian Rajaganesh, Hui Wei, Suresh Kumar, Marcello Nicoletti, Giovanni Benelli, Hydrothermal synthesis of titanium dioxide nanoparticles: mosquitocidal potential and anticancer activity on human breast cancer cells (MCF-7), Parasitol. Res. 115 (2016) 1085. [51] R. Sivaraj, P.K. Rahman, P. Rajiv, S. Narendhran, R. Venckatesh, Biosynthesis and characterization of Acalypha indica mediated copper oxide nanoparticles and evaluation of its antimicrobial and anticancer activity, Spectrochimic. Acta Part A: Mol. Biomol. Spectrosc. 129 (17) (2014) 255. [52] Amin Boroumand Moghaddam, Mona Moniri, Susan Azizi, Raha Abdul Rahim, Arbakariya Bin Ariff, Mohammad Navaderi, Rosfarizan Mohamad, Eco-friendly formulated zinc oxide nanoparticles: induction of Cell cycle arrest and apoptosis in the MCF-7 Cancer Cell line, Genes 8 (2017) 281. [53] Ebru Özturk, Ayşe Kübra Karaboga Arslan, Alim Hüseyin Dokumaci, Mükerrem Betül Yerer, Turk. Real-time analysis of impedance alterations by the effects of vanadium pentoxide on several carcinoma Cell lines, J. Pharm. Sci. 15 (1) (2018) 1. [54] Sri Vishnu Priya Ramaswamy, S. Narendhran, Rajeshwari Sivaraj, Potentiating effect of ecofriendly synthesis of copper oxide nanoparticles using brown alga: antimicrobial and anticancer activities, Bull. Mater. Sci. 39 (2) (2016) 361. [55] J. Emima Jeronsia, D.J. Vidhya Raj, L. Allwin Joseph, K. Rubini, S. Jerome Das, In vitro antibacterial and anticancer activity of copper oxide nanostructures in human breast cancer Michigan Cancer Foundation-7 cells, J. Med. Sci. 36 (4) (2016) 145.
754