Incorporation and release of diclofenac sodium using chitosan chemically modified with glutaraldehyde and ethylenediamine.

Diclofenac sodium (SD) is a widely used nonsteroidal anti-inflammatory drug (NSAID) with notable therapeutic relevance. In this study, chitosan was chemically modified with glutaraldehyde and ethylenediamine via a solvent-free synthesis route, aiming to develop an efficient and sustainable platform for drug adsorption and controlled release. The modified chitosan (MCGE) was thoroughly characterized by Fourier-transform infrared spectroscopy (FTIR), solid-state 13C nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and elemental analysis, confirming successful functionalization and enhanced thermal stability. Adsorption experiments conducted at pH 5 revealed a maximum diclofenac sodium uptake of 122.69 mg·g-1 within 90 min. Release studies demonstrated improved drug release at physiological pH (7.4), indicating favorable conditions for both gastrointestinal and systemic delivery. This study highlights the potential of MCGE as a biocompatible and thermally stable carrier for controlled drug delivery applications.