Synthesis of biocompatible and biodegradable 2-hydroxyethyl methacrylate-citric acid-acrylic acid-based pH-sensitive hydrogels

Abstract

It is more significant to investigate eco-friendly stimuli sensitive hydrogel because of greater application of pH-sensitive hydrogels in environmental and biomedical applications. The present work, the new pH-sensitive 2-hydroxyethyl methacrylate (HEMA) crosslinked with citric acid (CA) and acrylic acid (AA) based CA-HEMA-AA (CHA) hydrogels has been effectively synthesized via two-step polymerization process. The structural changes, surface morphology and thermal properties was carried out using FT-IR, SEM, TGA/DTA and DSC equipments. Swelling (S%) and equilibrium swelling studies has been performed in various conditions. The S% of C3H2A hydrogel found to have better value such as 900%, 1310%, 1020% in pH 3.0, 7.4, 10.0 compared to other hydrogels. The percentage of equilibrium water content of CHA hydrogel has showed in the range of 93.78—95.86%. The percentage of gel content has also been exhibited more at pH10 (basic medium) than acidic and neutral, due to lower interaction between the hydrogel and pH solution. After 56 days CHA hydrogel attained maximum 91% weight loss through biodegradation process. C3H2A hydrogel found to have good antibacterial activity against L. monocytogenes and V. cholera (100 µg/mL) strain. The percentage of cell viability of CHA hydrogel has been studied by Cytotoxicity MTT assay was used to estimate the cell viability of CHA hydrogel (10 µg/ml) possessed 78.88% to 81.11% of cell viability. These results underscore few insights into the impacts of CA and AA crosslinking on surface, thermal, biodegradation, antibacterial properties and cytotoxicity of adhesion concert of soft hydrogels. These observations showed that pH-tuning hydrogel may have superior prospective in simple and convenient approaches like biomedical, agrochemical, dye removal and toxic metal ion removal applications.