Faculty Publications
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Item 6-[3-(4-Fluorophenyl)-1H-pyrazol-4-yl]-3-[(2-naphthyloxy)methyl][1,2,4]triazolo[3,4-b][1,3,4]thiadiazole as a potent antioxidant and an anticancer agent induces growth inhibition followed by apoptosis in HepG2 cells(2010) Dhanya, D.; Isloor, A.M.; Shetty, P.; Satyamoorthy, K.; Bharath Prasad, A.S.In this paper we have investigated the in vitro antioxidant property of two triazolo-thiadiazoles, 6-[3-(4-fluorophenyl)-1H-pyrazol-4-yl]-3-[(2-naphthyloxy)methyl][1,2,4]triazolo[3,4-b][1,3,4]thiadiazole (FPNT) and 6-[3-(4-chlororophenyl)-1H-pyrazol-4-yl]-3-[(phenyloxy)methyl][1,2,4]triazolo[3,4-b][1,3,4]thiadiazole (CPPT) by spectrophotometric DPPH and ABTS radical scavenging methods as well as by lipid peroxide assay. The anticancer activity along with possible mechanism of action of triazolo-thiadiazoles in Hep G2 cells was explored using MTT assay, [3H] thymidine assay, flow cytometry and chromatin condensation studies. Both FPNT and CPPT exhibited a dose dependent cytotoxic effect on hepatocellular carcinoma cell line, HepG2. The IC50 value was very low for both the compounds when compared to standard drug, doxorubicin. Incorporation of [3H] thymidine in conjunction with cell cycle analysis suggested that FPNT inhibited the growth of HepG2 cells. Flow cytometric studies revealed more percentage of cells in sub-G1 phase, indicating apoptosis, which was further confirmed through chromatin condensation studies by Hoechst staining. FPNT was found to be a potent antioxidant when compared to the standard in DPPH, ABTS radical scavenging assays and lipid peroxidation studies. © 2010 .Item Novel organogel based lyotropic liquid crystal physical gels for controlled delivery applications(Elsevier Ltd, 2015) Singh, V.K.; Pal, K.; Banerjee, I.; Pramanik, K.; Anis, A.; Al-Zahrani, S.M.In this study, novel organogel based lyotropic liquid crystals (LLC) were prepared and investigated as controlled release matrices. The LLC gels were prepared using mixtures of Span 80-Tween 80 (1:2 w/w), aqueous solution of polyvinyl alcohol (10% w/w) and sesame oil. The prepared gels were characterized by microscopy, mechanical testing and thermal studies. The biocompatibility of the gels was tested against human keratinocytes. Metronidazole loaded gels were used for in vitro drug release and antimicrobial tests. The formation of water-in-oil emulsion gels was confirmed by fluorescent microscopy. Polarized micrographs showed the formation of lamellar structures within the aqueous phase of the matrices. Mechanical studies confirmed the viscoelastic nature of the gels with solid like consistency. The melting points of the gels were in the range of 44-51°C. The gels did not elicit any cytotoxic effect on the human keratinocytes. The release of metronidazole from the gels was diffusion mediated. The drug loaded gels showed good antimicrobial efficacy against Escherichia coli. ©2015 Published by Elsevier Ltd.Item Synthesis and antitubercular and antibacterial activity of some active fluorine containing quinoline–pyrazole hybrid derivatives(Elsevier B.V., 2016) Nayak, N.; Ramprasad, J.; Udayakumar, D.In an attempt to develop newer antitubercular and antibacterial agents against the increasing bacterial resistance, we have designed new quinoline–pyrazole analogs (8a–u) following the molecular hybridization approach. The structure of one of the final compounds, 8a was unambiguously confirmed by single crystal X-ray diffraction (SC-XRD) analysis. The target compounds were evaluated for their antitubercular activity against Mycobacterium tuberculosis and antibacterial activity against three common pathogenic bacterial strains. Four derivatives (8b, 8c, 8j and 8o) displayed significant antitubercular activity. The compounds derived from 8-trifluoromethylquinoline and 6-fluoroquinoline scaffolds with halogen substitution on the pyrazole ring exhibited superior inhibition activity than corresponding 6-methoxyquinoline analogs. The cytotoxic studies revealed that the active compounds are nontoxic to normal Vero cell lines with selectivity index values ?10, which indicate the suitability of these compounds for further drug development. The in silico molecular docking study demonstrated strong binding affinity of the compounds with the target enzymes (InhA, CYP121 and TMPK) of M. tuberculosis. Further, the in vitro antibacterial activity of compounds 8b, 8c, 8d and 8g is comparable with that of the reference drug, Ciprofloxacin. © 2016 Elsevier B.V.Item Synthesis of new pyrazole-triazole hybrids by click reaction using a green solvent and evaluation of their antitubercular and antibacterial activity(Springer Netherlands, 2016) Nayak, N.; Ramprasad, J.; Udayakumar, D.; Yogeeswari, P.; Sriram, D.; Santosh Kumar, H.S.S.; Peethambar, S.K.; Achur, R.A new series of pyrazole-based 1,2,3-triazole derivatives (6a-x) were synthesized by employing click reaction using a 2:1 mixture of PEG-400 and water as green solvent. The synthesized intermediate and final compounds were characterized by 1H NMR, 13C NMR, and mass spectra and elemental analysis techniques. The structure of one of the final compounds, 6a was evidenced by single crystal X-ray diffraction study. Among the twenty-four compounds, five compounds (6a, 6b, 6d, 6f, and 6g) showed significant antitubercular activity against Mycobacterium tuberculosis H37Rv with a minimum inhibitory concentration (MIC) ? 6.25 ?g/mL. The 4-(((5-(4-Chlorophenyl)-1-phenyl-1H-pyrazol-3-yl)methoxy)methyl)-1-cyclohexyl-1H-1,2,3-triazole (6g) was the most potent compound of the series, which showed a MIC of 3.13 ?g/mL. The cytotoxicity study of active anti-TB compounds on normal Vero cells revealed that the compounds are non-toxic with a high selectivity index (>37). Most of the pyrazole-1,2,3-triazole derivatives with a 4-chlorophenyl substitution at position-5 of the pyrazole ring showed a better anti-TB activity than the corresponding 4-bromophenyl or 4-methoxyphenyl substituted derivatives. The target compounds were also evaluated for their in vitro antibacterial activity and six compounds (6a, 6c, 6d, 6e, 6l, and 6w) showed promising inhibition activity against four tested strains. © Springer Science+Business Media Dordrecht 2015.Item Role of graphene quantum dots synthesized through pyrolysis in the release behavior of temperature responsive poly (N,N-diethyl acrylamide) hydrogel loaded with doxorubicin(Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2018) Havanur, S.; JagadeeshBabu, P.E.We have reported the synthesis and characterization of new drug carrier using Poly (N,N-diethyl acrylamide) (PDEA) and graphene quantum dots (GQDs). PDEA is a stimuli-responsive, macroporous polymer which has the ability to respond to change in surrounding temperature and addition of GQDs will help in improving the inherent characteristics of PDEA. In this research work, PDEA hydrogels along with GQDs have been synthesized by free radical polymerization. The effect of various concentrations of GQDs on the property of PDEA hydrogel was studied. The structural analysis of synthesized hydrogels was done using Fourier transform infrared spectroscopy (FT–IR). The internal surface morphology of porous hydrogels was observed using scanning electron microscope (SEM) micrographs. From the analysis, it has been observed that the equilibrium swelling ratio (ESR) and reswelling kinetics of the hydrogel significantly increased as the GQDs content was varied. The cancer drug (an anthracycline that is used for cancer chemotherapy) Doxorubicin (DOX) release behavior was studied and found that the performance of hydrogel is dependent on hydrogel composition, time, and surrounding temperature. The cytotoxicity of GQDs incorporated PDEA hydrogels gave a significant report which supports the potential application of hydrogel as an intelligent drug carrier. © 2018, © 2018 Taylor & Francis Group, LLC.Item Synthesis and optimization of poly (N,N-diethylacrylamide) hydrogel and evaluation of its anticancer drug doxorubicin’s release behavior(Springer London, 2019) Havanur, S.; Farheenand, V.; JagadeeshBabu, P.E.A macroporous temperature-responsive poly(N,N-diethylacrylamide) (PDEA) hydrogel was synthesized and optimized through free radical polymerization. The optimized hydrogel was achieved by evaluating the swelling characteristics, physical stability and mechanical strength through altering the components namely concentration of N,N-diethylacrylamide (monomer), ammonium peroxodisulfate (initiator), N,N?-methylbisacrylamide (cross-linker) and N,N,N?,N?-tetramethylethylenediamine (accelerator). The equilibrium swelling behavior was performed gravimetrically, and the PDEA hydrogel synthesized at 36 °C exhibited a maximum swelling of 18.332 g.g ?1 . Also, the LCST of the prepared PDEA hydrogel was found to be around 29 °C. However, the results of time-controlled swelling and deswelling kinetics indicated that hydrogels are temperature sensitive. Further, characterization of the hydrogel was performed using scanning electron microscopy, differential scanning calorimetry, thermal gravimetric analysis, and Fourier transform infrared spectroscopy. The hydrogel was assessed for its cytotoxicity in MDA-MB-231 cell line by MTT assay. The release behavior of anticancer drug doxorubicin (DOX), a hydroxyl derivative of anthracycline, was studied at above and below the LCST temperature. It was found that the DOX release from the DOX-loaded hydrogels was significantly improved when the surrounding temperature of the release media was increased near to physiological temperature. The cumulative release profile of hydrogel at different temperatures was fitted to different kinetic model equations and non-Fickian diffusion release mechanism was revealed. These results suggest that PDEA has a potential application as an intelligent drug carrier. © 2018, Iran Polymer and Petrochemical Institute.Item Ionic liquid promoted facile one-pot synthesis of phenothiazine-thiazolidin-4-ones as potent antitubercular agents via mycobacterial ATP synthase inhibition(Elsevier B.V., 2025) Reddyrajula, R.; Etikyala, U.; Mahapathra, H.C.; Udaybhan, R.A.; Vijjulatha, V.; Udayakumar, U.The mycobacterial ATP synthase is responsible for the optimal growth, metabolism and viability of mycobacteria, establishing it as a validated target for the development of anti-TB therapeutics. Herein, we report the facile and efficient one-pot three component synthesis of 2-(10H-phenothiazin-3-yl)-3-substituted thiazolidin-4-one derivatives by using ionic liquid, 1?butyl?3-methylimidazolium bromide [Bmim]Br and their inhibitory potency against mycobacterium tuberculosis H37Rv strain (ATCC-27,294). Compound T27 exhibited the highest inhibition activity with an MIC of 0.78 ?g/mL, which is twofold and fourfold superior (in terms of the MIC values) to the standard first-line TB drugs isoniazid (MIC: 1.56 ?g/mL) and pyrazinamide (MIC: 3.12 ?g/mL) respectively. Two other compounds (T25 and T30) are equipotent as the isoniazid. The SAR studies revealed that insertion of 1,2,3-traizole and thiozolidine-2-one rings enhance the anti-TB activity in most of the tested compounds. Also, compound T27 was screened for mycobacterial ATP synthase inhibition activity and it exhibited an IC50 of 0.735 µM in M. smegmatis IMVs. Further, toxicity evaluation against VERO cell lines confirmed null cytotoxicity (selectivity index > 70) of the potent analogues. The title compounds are highly specific towards to the M. tb strain, i.e., most of the compounds exhibited moderate inhibitory potency against the tested bacterial strains (MIC ? 6.25 ?g/mL). In addition, molecular docking was employed against the active site of the ATP synthase enzyme to validate the binding mechanism and in vitro activity profile of the phenothiazine derivatives. Furthermore, in silico ADME and pharmacokinetic parameters’ prediction indicated good oral bioavailability. © 2024 Elsevier B.V.Item Imidazo[1,2-a]pyrimidine-Linked Pyridine, Pyrazine, and Pyrimidine Derivatives: Design, Synthesis, and Antitubercular Activity Evaluation(John Wiley and Sons Inc, 2025) Puttachari, D.; Naik, S.; Veeranagaiah, N.S.; Udayakumar, U.In this study, a molecular hybridization strategy was used to design a series of imidazo[1,2-a]pyrimidine-linked pyridine, pyrazine, and pyrimidine derivatives (T1–T20) and the hybrid compounds were synthesized via a multistep procedure. The structure of one of the target compounds T11, was studied using single-crystal X-ray diffraction investigation. These final molecules were thoroughly tested against Mycobacterium tuberculosis H37Rv strain, and compound T11 showed the best activity with MIC of 0.8 µg/mL, while compounds T5 and T18 showed promising inhibition activity (MIC 3.12 µg/mL). The target compounds were further tested for antibacterial activity against Staphylococcus aureus and Escherichia coli, finding the MIC and MBC values. Many of the compounds exhibited notable antibacterial properties. The promising anti-TB drugs (T5, T11, and T18) were shown to be nontoxic in toxicity studies on VERO cell lines. The combined results from in silico ADME, molecular docking, and DFT studies indicate that the active compounds possess strong potential as antitubercular candidates. © 2025 Wiley-VCH GmbH.Item Investigating the role of WEDM surface texturing in the degradation and biocompatibility of Mg–Zn–Ca alloy(KeAi Publishing Communications Ltd., 2025) Aswith Babu, I.; Sekar, P.; Prabhu, A.; Narendranath, S.; Balan, A.S.S.Magnesium (Mg) alloy-based biodegradable implants are gaining popularity for their low density, high strength, and biocompatibility. The corrosion and wear performance of Mg is poor in physiological environments, leading to premature failure. Surface modification, particularly through surface texturing, reduces the effective contact area of Mg–Zn–Ca alloy with corrosive media and tribological partners, potentially optimizing its degradation kinetics and cytocompatibility. Wire Electric Discharge Machining (WEDM) offers a stable oxide layer on the surface, unlike laser surface texturing, which may thermally damage the Mg alloy. In this study, three types of textures, mainly Wavy Texture (WT), microchannels (MC), and micropillars (MP), were created using WEDM on the Mg–Zn–Ca samples, and their corrosion, wear, cytotoxicity, and cell adhesion performance were evaluated. Texturing on the surface of the samples enhanced the corrosion performance, from 3.14 mm/year for the untextured sample to 0.98 mm/year for the micropillar textured sample, representing a 68.8 % reduction. This improvement after texturing is attributed to the superior surface finish (1.049 ?m) and increased hydrophobicity (130.3°), equating to a 50.8 % improvement. The coefficient of friction (COF) value decreased from 0.364 for an untextured sample to 0.208 for microchannels, a 42.9 % reduction, due to the entrapment of debris in the textures and effective heat transfer. The samples' cell adhesion and cell viability have been improved after texturing. The combination of cytocompatibility, appropriate mechanical properties, and a reduced bio-corrosion rate highlights the potential of this surface texturing method, utilizing WEDM, as a promising approach to enhance biodegradable implant materials. © 2025 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltdé This is an open access article under the CC BY license. http://creativecommons.org/licenses/by/4.0/Item Amidated pectin and gum Arabic aldehyde-based pH-sensitive hydrogel for targeted colonic treatment(Elsevier B.V., 2025) Singh, H.; JagadeeshBabu, J.; Mohan Balakrishnan, R.In this study, a novel pH-responsive hydrogel was developed by crosslinking amidated pectin(AmPec) with oxidised gum Arabic(GAA) by hydrogen and hemiacetal bonding without the need for toxic crosslinkers for oral delivery of doxorubicin to treat colon cancer. FTIR and NMR confirmed the amidation of pectin and oxidation of Gum Arabic. FTIR confirmed the formation of hydrogen and hemiacetal bonds in the hydrogel. X-ray diffraction(XRD) spectra showed the amorphous characteristic of AmPec-GAA hydrogels compared to their polymer precursors, confirming the formation of a crosslinked hydrogel. AmPec-GAA15 hydrogel swelled around 655 %±39.90 at pH 7.4 compared to 181 %±7.94 swelling at pH 1.2 after 72 h. The release of doxorubicin also followed the same trend, with only 4.48 % ±0.89 doxorubicin release at pH 1.2, while the drug release increased to 68.10 %±3.73 at pH 7.4 after 48 h. SEM micrographs revealed the macroporous and interconnected hydrogel structure with fewer pores in the hydrogel swelled in pH 1.2 compared with pH 7.4, where more visible pores were observed, indicating the pH-sensitive behaviour of the hydrogel. Hydrogel possessed excellent thermal and mechanical stability as revealed by TGA and rheology study, which can also be explored for tissue engineering applications. MTT assay on L929 cells showed cell viability above 95.1 %±,0.0074, demonstrating hydrogels' non-toxic and biocompatible behaviour. Meanwhile, Dox-loaded hydrogel induced higher cytotoxicity against HT-29 cells than free Dox in a dose-dependent manner. Therefore, the developed hydrogel can be used as an effective oral carrier to deliver doxorubicin to colon cancer while hindering its release in the stomach and thus preventing associated toxicity. © 2025 Elsevier B.V.