Faculty Publications
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Item Synthesis and characterization of temperature sensitive P-NIPAM macro/micro hydrogels(Elsevier B.V., 2011) JagadeeshBabu, P.E.; Suresh Kumar, R.; Maheswari, B.A thermo responsive macro porous poly(N-isopropylacrylamide) hydrogel was synthesized using free radical polymerization. The reaction was optimized by varying the reaction temperature, monomer, cross-linker and initiator based on the strength and swelling characteristics of the hydrogel. The morphology of the macro hydrogel was observed using scanning electron microscope (SEM). The swelling behavior of the macro hydrogel was performed gravimetrically and found that the gel synthesized at 36 °C had maximum deswelling ratio of 34.5 (-). These optimized values were further used to synthesis micro hydrogels using water-oil (w/o) emulsion technique. The morphology of the micro hydrogels were observed through SEM. Effect of water-oil ratio and stirrer speed on the mean particle size of the micro hydrogels were studied. Micro hydrogels synthesized at 1:1.5. w/o ratio and at 800. rpm had perfect spherical shape and had least particle mean diameter of 0.74 ?m, with SD of 0.5. Dye release kinetics with respect to temperature and time were studied using methylene blue solution. The release kinetic studies of micro hydrogel showed higher sustained release for 56. h compared to the macro hydrogel. © 2011 Elsevier B.V.Item Controlled release of nutrients to mammalian cells cultured in shake flasks(2012) Hegde, S.; Pant, T.; Pradhan, K.; Badiger, M.; Gadgil, M.Though cell culture-based protein production processes are rarely carried out under batch mode of operation, cell line and initial process development operations are usually carried out in batch mode due to simplicity of operation in widely used scale down platforms like shake flasks. Nutrient feeding, if performed, is achieved by bolus addition of concentrated feed solution at different intervals, which leads to large transient increases in nutrient concentrations. One negative consequence is increased waste metabolite production. We have developed a hydrogel-based nutrient delivery system for continuous feeding of nutrients in scale down models like shake flasks without the need for manual feed additions or any additional infrastructure. Continuous delivery also enables maintaining nutrient concentrations at low levels, if desired. The authors demonstrate the use of these systems for continuous feeding of glucose and protein hydrolysate to a suspension Chinese Hamster Ovary (CHO) culture in a shake flask. Glucose feeding achieved using the glucose-loaded hydrogel resulted in a 23% higher integral viable cell density and an 89% lower lactate concentration at the end of the culture when compared with a bolus-feed of glucose. © 2011 American Institute of Chemical Engineers (AIChE).Item Role of N-vinyl-2-pyrrolidinone on the thermoresponsive behavior of PNIPAm hydrogel and its release kinetics using dye and vitamin-B12 as model drug(2014) Maheswari, B.; JagadeeshBabu, P.E.; Agarwal, M.Temperature-sensitive hydrogels hold great promise in biological applications as they can respond to changes in physiological temperature to produce a desired effect like controlled drug delivery. In this study, a series of poly(N-isopropylacrylamide-co-N-vinyl-2-pyrrolidinone) thermosensitive hydrogels were synthesized by radical copolymerization of NIPAm with 1-vinyl-2-pyrrolidinone (NVP). By altering the initial NIPAm/NVP mole ratios, copolymers were synthesized to have their own distinctive lower critical solution temperature which was established using differential scanning calorimetry. The swelling behavior of the hydrogel was analyzed gravimetrically and it was observed that reswelling rate increases with increasing NVP mole ratio. Further characterizations of the hydrogels were performed using Fourier transform infrared spectroscopy and scanning electron microscopy. Release kinetics with respect to temperature was studied using methylene blue dye solution and vitamin B12. Kinetic modeling of the release profile revealed that the release mechanism is a non-Fickian diffusion mechanism. These results suggested that this material has potential application as intelligent drug carriers. The quantities of residual monomers in the PIV4 hydrogel were determined by HPLC method, and the results show almost complete conversion. © 2013 Taylor & Francis.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 Nanohydroxyapatite Reinforced Chitosan Composite Hydrogel with Tunable Mechanical and Biological Properties for Cartilage Regeneration(Nature Publishing Group Houndmills Basingstoke, Hampshire RG21 6XS, 2019) Kumar, B.Y.S.; Isloor, A.M.; Mohan Kumar, G.C.M.; Siddique, I.; Asiri, A.M.With the continuous quest of developing hydrogel for cartilage regeneration with superior mechanobiological properties are still becoming a challenge. Chitosan (CS) hydrogels are the promising implant materials due to an analogous character of the soft tissue; however, their low mechanical strength and durability together with its lack of integrity with surrounding tissues hinder the load-bearing application. This can be solved by developing a composite chitosan hydrogel reinforced with Hydroxyapatite Nanorods (HANr). The objective of this work is to develop and characterize (physically, chemically, mechanically and biologically) the composite hydrogels loaded with different concentration of hydroxyapatite nanorod. The concentration of hydroxyapatite in the composite hydrogel was optimized and it was found that, reinforcement modifies the hydrogel network by promoting the secondary crosslinking. The compression strength could reach 1.62 ± 0.02 MPa with a significant deformation of 32% and exhibits time-dependent, rapid self-recoverable and fatigue resistant behavior based on the cyclic loading-unloading compression test. The storage modulus value can reach nearly 10 kPa which is needed for the proposed application. Besides, composite hydrogels show an excellent antimicrobial activity against Escherichia coli, Staphylococcus aureus bacteria’s and Candida albicans fungi and their cytocompatibility towards L929 mouse fibroblasts provide a potential pathway to developing a composite hydrogel for cartilage regeneration. © 2019, The Author(s).Item Experimental Demonstration of Compact Polymer Mass Transfer Device Manufactured by Additive Manufacturing with Hydrogel Integration to Bio-Mimic the Liver Functions(MDPI, 2023) Narendran, G.; Walunj, A.; Kumar, A.M.; Jeyachandran, P.; Awwad, N.S.; Ibrahium, H.A.; Gorji, M.R.; Arumuga Perumal, D.A.In this paper, we designed and demonstrated a stimuli-responsive hydrogel that mimics the mass diffusion function of the liver. We have controlled the release mechanism using temperature and pH variations. Additive manufacturing technology was used to fabricate the device with nylon (PA-12), using selective laser sintering (SLS). The device has two compartment sections: the lower section handles the thermal management, and feeds temperature-regulated water into the mass transfer section of the upper compartment. The upper chamber has a two-layered serpentine concentric tube; the inner tube carries the temperature-regulated water to the hydrogel using the given pores. Here, the hydrogel is present in order to facilitate the release of the loaded methylene blue (MB) into the fluid. By adjusting the fluid’s pH, flow rate, and temperature, the deswelling properties of the hydrogel were examined. The weight of the hydrogel was maximum at 10 mL/min and decreased by 25.29% to 10.12 g for the flow rate of 50 mL/min. The cumulative MB release at 30 °C increased to 47% for the lower flow rate of 10 mL/min, and the cumulative release at 40 °C climbed to 55%, which is 44.7% more than at 30 °C. The MB release rates considerably increased when the pH dropped from 12 to 8, showing that the lower pH had a major impact on the release of MB from the hydrogel. Only 19% of the MB was released at pH 12 after 50 min, and after that, the release rate remained nearly constant. At higher fluid temperatures, the hydrogels lost approximately 80% of their water in just 20 min, compared to a loss of 50% of their water at room temperature. The outcomes of this study may contribute to further developments in artificial organ design. © 2023 by the authors.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.