Preparation and characterization of pH‐sensitive carboxymethyl cellulose‐based hydrogels for controlled drug delivery

Abstract A novel biopolymer‐based hydrogel with pH‐responsive behavior was synthesized by free radical polymerization of acrylic acid and methacrylic acid onto carboxymethylcellulose. The effects of initiator concentration, crosslinker concentration, acrylic acid and methacrylic acid total volume and acrylic acid percentage on water absorbency were studied using central composite design with the response surface method (RSM). The results indicate that the maximum water absorbency in distilled water is 103 g g −1 and the optimum conditions determined using RSM are: initiator concentration, 0.006105 mol L −1 ; crosslinker concentration, 0.009035 mol L −1 ; acrylic acid and methacrylic acid total volume, 2 mL; acrylic acid percentage, 50%, in a system of 35 mL total volume. The optimized hydrogel was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy and thermogravimetric analysis, and its pH‐responsive behavior was also evaluated using acidic and basic solutions for its possible use in control drug delivery. In this respect, ofloxacin was used as a drug model and experimental data showed that the hydrogel is a possible candidate for injectable drug delivery. © 2022 Society of Industrial Chemistry.