DESIGN, FABRICATION AND EVALUATION OF NATURAL POLYMER-BASED MICROBEADS FOR THE PROLONGED RELEASE OF ANTIVIRAL DRUG
Objectives: The present study designed to prepare and evaluate valacyclovir hydrochloride-loaded hydrogel microbeads using a sodium alginate-xanthan gum polymeric system to get sustained drug release and potential for sustained delivery. Methods: Microbeads were formulated by the ionic gelation technique using variable ratios of sodium alginate and xanthan gum, cross-linked with aluminum chloride (1% and 2% w/v). The formulations were tested using various evaluation methods, that is, percentage yield, particle size, swelling index, drug entrapment efficiency, surface morphology study by scanning electron microscopy (SEM), drug-polymer compatibility fourier transform infrared spectroscopy (FTIR), and in vitro drug release. Release kinetics were examined by means of various mathematical models. Results: The microbeads were spherical with rough surfaces, as established by SEM, and exhibited no chemical incompatibility as per FTIR analysis. Particle size ranged from 661.67±10.65 μm to 713.67±12.33 μm, indicating uniformity. Percentage yield (79.80–88.11%) and drug entrapment efficiency (23.26–39.04%) exhibited higher values in alginate-rich formulations. Swelling index ranged between 217.00±20.60% and 304.00±16.77%, affected by polymer ratio along with cross-linking density. In vitro drug release studies confirmed a sustained release profile, with F1 presenting the highest release (40.08%) and F6 the lowest (28.91%) through 300 min. Drug release mainly followed the Korsmeyer-Peppas model, signifying a diffusion-controlled mechanism with polymer relaxation. Conclusion: The study ensures that physical characteristics along with drug release behavior of the microbead were pointedly influenced by polymer composition in addition to cross-linking concentration. The prepared sodium alginate-xanthan gum system demonstrates potential as an active sustained drug delivery system for valacyclovir hydrochloride.