Faculty Publications
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Item Sacrificial polystyrene template assisted synthesis of tunable pore size hollow core-shell silica nanoparticles (HCSNs) for drug delivery application(American Institute of Physics Inc. subs@aip.org, 2019) Deepika, D.; JagadeeshBabu, J.Hollow core-shell silica nanoparticles (HCSNs) with desirable interior space have attracted intensive interest in the field of controlled drug delivery. In the present research work facile two-step method was employed to synthesize HCSNs by using sacrificial polystyrene (PS) template. Monodispersed spherical polystyrene nanoparticles with size range 200-250 nm were synthesized by emulsion polymerization method. Silica was coated on PS template using TEOS as precursor and cetyltrimethyl ammonium bromide (CTAB) as the shell structure directing agent. Complete removal of the template particles was achieved by calcination at 550 °C confirmed by fourier transform infrared spectroscopy (FTIR). Variation in pore size was attained by altering ethanol/water volume ratio and visualized in scanning electron microscope (SEM). Average specific surface area of HCSNs verified by Brunauer Emmett Teller (BET) method observed to be 842.57 m2/g. Drug release behavior was investigated using doxorubicin as model drug by varying pore size of HCSNs, displayed a pore size dependent release. HCSNs with reduced pore size (2.2 nm) showed maximum delay in the doxorubicin release, demonstrated the potential application of HCSNs in targeted drug delivery. © 2019 Author(s).Item Synthesis and characterisation of TiO2 nanofibre/cellulose acetate nanocomposite ultrafiltration membrane(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2017) Neelapala, S.D.; Nair, A.K.; JagadeeshBabu, J.Nanofibres of TiO2 were synthesised by hydrothermal routine. Cellulose acetate/TiO2 nanofibre composite membranes were synthesised via blending TiO2 nanofibre in cellulose acetate solutions in 1-methyl-2-pyrrolidone. In order to study the effect of addition of nanofibre, membranes with various composition were synthesised, first by keeping cellulose acetate to 1-methyl-2-pyrrolidone ratio constant and second by decreasing cellulose acetate concentration with increasing addition of TiO2 nanofibre. The membranes were characterised using scanning electron microscope and X-ray diffraction. Hydrophilicity of the membranes was evaluated in terms of contact angle measurements and water uptake study. Permeation characteristics were determined in terms of pure water flux and bovine serum albumin rejection. Antifouling property was studied in terms of flux recovery after rejection. Remarkable improvement in membrane flux and antifouling properties is achieved by the addition of TiO2 nanofibres. © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.Item Synthesis and characterization of silver decorated polysulfone/cellulose acetate hybrid ultrafiltration membranes using functionalized TiO2 nanoparticles(Desalination Publications dwt@deswater.com, 2017) Sri, K.S.; Nair, A.K.; JagadeeshBabu, J.Amine functionalized TiO2 nanoparticles were synthesized via surface reaction with 3-Aminopropyl triethoxysilane. These nanoparticles were added to polysulfone and cellulose acetate blend casting solutions in 1-Methyl-2-pyrrolidone to form hybrid membranes by phase inversion. The amine groups on the surface of the membranes were used as absorption sites for silver nanoparticles. The obtained membranes were characterized using Fourier Transform Infra Red spectroscopy, Scanning electron microscope and X-ray diffraction. Water uptake studies and contact angle measurements were done to evaluate hydrophilicity of the membranes. Pure water flux studies of the membrane were carried out in a dead end filtration unit. Rejection and antifouling studies were carried out using bovine serum albumin as a model protein. The hybrid membranes exhibited better permeability and fouling resistance. The hybrid membranes with silver decoration on the surface showed microbial resistance. © 2017 Desalination Publications. All rights reserved.Item TiO2 nanosheet-graphene oxide based photocatalytic hierarchical membrane for water purification(Elsevier B.V., 2017) Nair, A.K.; JagadeeshBabu, J.There is a rising concern over the toxicity of nanomaterials which emphasizes the need for reforms in application of nanomaterials in water treatment. A hierarchical membrane with a thin layer of photocatalyst coated on top of the membrane surface has emerged as a better alternate for immobilization of photocatalyst. Studies have revealed that nanoparticles are not pliable for synthesis of hierarchical membranes due to their smaller size and low stability after deposition. TiO2 nanosheets serve as better alternate due their thin structure which enables stable layer formation. Integrating the nanosheets with modifiers like graphene oxide can further enhance the photocatalytic activity. The sheet structure of graphene oxide enhances stable film formation and also acts as support for interconnecting TiO2 nanosheets. In the present work, TiO2 nanosheets are modified with graphene oxide and used to develop a hierarchical membrane by depositing a catalyst coating on a support membrane. The hierarchical membrane performance was studied using Congo red dye as model pollutant and the effect of catalyst loading on the permeate flux and dye removal were analyzed. © 2017 Elsevier B.V.Item Photocatalytic activity of ZnO-WO3 for diclofenac degradation under visible light irradiation(Elsevier B.V., 2019) Mugunthan, E.; Saidutta, M.B.; JagadeeshBabu, J.Diclofenac is known to be a persistent pharmaceutical compound, and their effective removal from water sources has been a rising concern. This study reports the visible light irradiated photocatalytic degradation of diclofenac using ZnO-WO3 mixed oxide catalysts, prepared by the hydrothermal method with variation in molar ratios of tungsten precursor. The prepared catalysts were characterized using a different technique, and the photocatalytic activity has been tested under visible light irradiation. Adsorption isotherm studies were performed to elucidate the preferential adsorption nature of the mixed oxide catalyst. The interaction of diclofenac and the prepared mixed oxides is based on the positively charged ZnO-WO3 surface and anionic diclofenac at solution pH 6. The adsorption and photodegradation kinetics is best expressed by the Langmuir isotherm model and pseudo-first-order kinetic model, respectively. Results indicated that all the prepared catalysts exhibited better catalytic activity than the bare ZnO under the visible light irradiation. The catalyst prepared with a molar ratio of 10:1 is proven to be an efficient catalyst and achieved 76%mineralization of diclofenac during the irradiation. The effect of operating variables like pH, initial diclofenac concentration, and catalyst loading was investigated and reported. The ZnO-WO3 mixed oxide catalysts were showed better stability, and the results revealed that the photocatalytic efficiency was retained up to 80% over the repeated reaction cycles. Several intermediate compounds formed during the photocatalytic reaction have been analyzed using LC–MS, and their degradation pathways have been found to primarily follows hydroxylation, dechlorination and decarboxylation reactions. © 2019 Elsevier B.V.Item Poly(N,N-diethyl acrylamide)/functionalized graphene quantum dots hydrogels loaded with doxorubicin as a nano-drug carrier for metastatic lung cancer in mice(Elsevier Ltd, 2019) Havanur, S.; Batish, I.; Cheruku, S.P.; Gourishetti, K.; JagadeeshBabu, J.; Kumar, N.Cancer has emanated as a daunting menace to human-kind even though medicine, science, and technology has reached its zenith. Subsequent scarcity in the revelation of new drugs, the exigency of salvaging formerly discovered toxic drugs such as doxorubicin has emerged. The invention of drug carrier has made drug delivery imminent which is ascribable to its characteristic traits of specific targeting, effective response to stimuli and biocompatibility. In this paper, the nanoscale polymeric drug carrier poly(N,N-diethyl acrylamide) nanohydrogel has been synthesized by inverse emulsion polymerization. Lower critical solution temperature of the polymeric carrier has been modified using graphene quantum. The particle size of pure nanohydrogel was in the range of 47 to 59.5 nm, and graphene quantum dots incorporated nanohydrogels was in the range of 68.1 to 87.5 nm. Doxorubicin (hydroxyl derivative of anthracycline) release behavior as a function of time and temperature was analyzed, and the Lower critical solution temperature of the synthesized nanohydrogels has been found to be in the range of 28–42 °C. Doxorubicin release characteristics have improved significantly as the surrounding temperature of the release media was increased near to physiological temperature. Further, the cumulative release profile was fitted in the different kinetic model and found to follow a Fickian diffusion release mechanism. The hydrogel was assessed for its cytotoxicity in B16F10 cells by MTT assay. In-vivo studies were done to study the lung metastasis by melanoma cancer and the results showed a rational favorable prognosis which was confirmed by evaluating hematological parameters and the non-immunogenic nature of nanohydrogel by cytokine assay. Comprehensively, the results suggested that poly(N,N-diethyl acrylamide) nanohydrogels have potential application as an intelligent drug carrier for melanoma cancer. © 2019 Elsevier B.V.Item Computational analysis of therapeutic enzyme uricase from different source organisms(Bentham Science Publishers P.O. Box 294 Bussum 1400 AG, 2020) Nelapati, A.K.; JagadeeshBabu, J.Background: Hyperuricemia and gout are the conditions, which is a response of accumulation of uric acid in the blood and urine. Uric acid is the product of purine metabolic pathway in humans. Uricase is a therapeutic enzyme that can enzymatically reduces the concentration of uric acid in serum and urine into more a soluble allantoin. Uricases are widely available in several sources like bacteria, fungi, yeast, plants and animals. Objective: The present study is aimed at elucidating the structure and physiochemical properties of uricase by insilico analysis. Methods: A total number of sixty amino acid sequences of uricase belongs to different sources were obtained from NCBI and different analysis like Multiple Sequence Alignment (MSA), homology search, phylogenetic relation, motif search, domain architecture and physiochemical properties including pI, EC, Ai, Ii, and were performed. Results: Multiple sequence alignment of all the selected protein sequences has exhibited distinct difference between bacterial, fungal, plant and animal sources based on the position-specific existence of conserved amino acid residues. The maximum homology of all the selected protein sequences is between 51-388. In singular category, homology is between 16-337 for bacterial uricase, 14-339 for fungal uricase, 12-317 for plants uricase, and 37-361 for animals uricase. The phylogenetic tree constructed based on the amino acid sequences disclosed clusters indicating that uricase is from different source. The physiochemical features revealed that the uricase amino acid residues are in between 300-338 with a molecular weight as 33-39kDa and theoretical pI ranging from 4.95-8.88. The amino acid composition results showed that valine amino acid has a high average frequency of 8.79 percentage compared to different amino acids in all analyzed species. Conclusion: In the area of bioinformatics field, this work might be informative and a stepping-stone to other researchers to get an idea about the physicochemical features, evolutionary history and structural motifs of uricase that can be widely used in biotechnological and pharmaceutical industries. Therefore, the proposed in silico analysis can be considered for protein engineering work, as well as for gout therapy. © 2020 Bentham Science Publishers.Item Sacrificial sulphonated polystyrene template-assisted synthesis of mesoporous hollow core-shell silica nanoparticles for drug-delivery application(Springer, 2020) Doddamani, D.; JagadeeshBabu, J.Spherical mesoporous hollow core-shell silica nanoparticles (HCSNs) of size 200 ± 50 nm with tunable thickness from 20 to 60 nm are synthesized using a sacrificial sulphonated polystyrene (PS, particle size 160 nm) template. A facile method is adopted for the sulphonation of PS using sulphuric acid, which enhanced the negative charge on the surface of PS as confirmed by zeta potential analysis and Fourier transform infrared radiation analysis. The thickness of the silica shell is tuned by altering the concentration of the silica precursor and is found to increase due to the use of the sulphonated PS template. N2 adsorption/desorption studies reported the variation of specific surface area of HCSNs from 644.1 to 197.8 m2 g?1 and average pore size from 1.55 to 3.4 nm. The drug release behaviour of HCSNs with different shell thicknesses is investigated using doxorubicin as the model drug. A delay in the drug release for ~300 min is successfully achieved by employing HCSNs with enhanced thickness of 60 nm. Application of HCSNs in targeted drug delivery was further supported by the in-vitro cytotoxicity studies carried out on lung adenocarcinoma cells. © 2020, Indian Academy of Sciences.Item Photocatalytic degradation of p-nitrophenol using biologically synthesized ZnO nanoparticles(Springer Science and Business Media Deutschland GmbH, 2021) Kadam, V.V.; Shanmugam, S.D.; JagadeeshBabu, J.; Mohan Balakrishnan, R.M.The present work deals with the photocatalytic degradation of p-nitrophenol as it is a United States Environmental Protection Agency-listed priority pollutant and has adverse environmental and health effects. To eradicate the detrimental environmental impact of p-nitrophenol, the biologically synthesized ZnO nanoparticles were used as a photocatalyst. The degradation of p-nitrophenol was confirmed by decreasing the absorbance value at a characteristic wavelength of 317 nm using the UV-vis spectrophotometer. Reaction parameters such as ZnO photocatalyst concentration of 0.1 g/L at pH 11 in the presence of H2O2 (5 mM) were found to be optimum conditions for p-nitrophenol degradation. The photocatalytic degradation was slowly enhanced in the presence of H2O2 as an electron acceptor. The kinetics of nitrophenol degradation was studied, which follows the pseudo-first-order reaction. The photocatalytic degradation of p-nitrophenol was characterized by using total organic carbon, chemical oxygen demand, and high-performance liquid chromatography analyses. This method is found to be effective as it is environmentally friendly, free of toxic chemicals. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.Item Fluorometric detection of bisphenol A using ?-cyclodextrin-functionalized ZnO QDs(Springer Science and Business Media Deutschland GmbH, 2021) Kadam, V.V.; Mohan Balakrishnan, R.M.; JagadeeshBabu, J.The estrogenic property of bisphenol A (BPA) leads to potential adverse health and ecological effects. A simple, selective, and cost-effective sensor capable of detecting BPA would have a noteworthy relevance for the environmental system. The present work illustrates the synthesis and characterization of ?-cyclodextrin (?-CD) functionalized zinc oxide (ZnO) quantum dots (QDs) for the selective detection of BPA. BPA has a fluorescence quenching effect on functionalized ZnO QDs, and the decrease in fluorescence intensity is associated with the BPA concentration between 2 and 10 ?M. Under the optimum reaction condition, a good linear correlation was obtained between relative fluorescence-quenching intensity of ?-cyclodextrin-functionalized ZnO QDs and BPA concentration (R2 = 0.9891). The lower detection limit of functionalized QDs for BPA was estimated to be 0.19 ?M, which is lower than the toxic limits in aquatic biota. The fluorescence-based detection of BPA may be ascribed to the electron transfer mechanism, which is elucidated with scientific details from the literature. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.