Development of carboxymethyl tamarind gum-based composite hydrogel films for wound dressing applications

Abstract Carboxymethyl tamarind gum (CMTG) is an anionic polymer gaining attention for its potential in drug delivery applications. In the present study, composite hydrogel films composed of CMTG and flaxseed mucilage (FSM) were developed for wound dressing applications. According to previous reports, hydrogel films prepared using CMTG alone exhibited poor matrix integrity and limited swelling capacity. To overcome these limitations, FSM was incorporated due to its highly hydrophilic nature, excellent water-holding capacity, and superior swelling characteristics, which are expected to enhance the overall performance of the composite hydrogel films. The composite hydrogel films were prepared by using solvent casting method. The developed hydrogel films were evaluated for weight loss, thickness, carboxyl content, contact angle, and swelling. The hydrogel films were characterized by attenuated total reflectance–Fourier transform infrared (ATR–FTIR) and thermal analysis. The drug loading was initiated by using diffusion mechanism. The drug release was studied in Tris HCl buffer pH 7.4. The physicochemical properties of the hydrogel films, including weight loss, thickness, carboxyl content, and contact angle, were influenced by the concentrations of citric acid and FSM. The optimized films showed enhanced swelling capacity (up to 37.83 g/g), superior to CMTG-alone films. The films were hemocompatible and exhibited minimal protein adsorption (<0.5 %). In addition, they demonstrated favorable water vapor permeability and effectively resisted microbial penetration. Drug release studies with metronidazole revealed a non-Fickian diffusion mechanism. ATR–FTIR and thermogravimetric analyses confirmed crosslinking between CMTG and citric acid, along with entanglement of FSM polymeric chains within the hydrogel matrix. The CMTG–FSM composite hydrogel films offer enhanced performance and biocompatibility, making them promising candidates for wound dressing applications.