FORMULATION AND IN-VITRO CHARACTERIZATION OF CHLORPHENIRAMINE MALEATE-LOADED MUCOADHESIVE MICROSPHERES INCORPORATED IN IN-SITU NASAL GEL

Abstract

Background: Nasal drug delivery offers rapid onset of action and avoids first-pass metabolism; however, conventional formulations suffer from rapid mucociliary clearance. Mucoadhesive microspheres incorporated into in-situ nasal gels can enhance nasal residence time and sustain drug release. Chlorpheniramine maleate, a widely used antihistamine, can benefit from such delivery to reduce systemic side effects and improve local efficacy. Methods: Chlorpheniramine maleate-loaded mucoadhesive microspheres were prepared using chitosan as the mucoadhesive polymer and sodium tripolyphosphate (TPP) as the cross-linking agent via the emulsification cross-linking method. Formulations F1–F9 were evaluated for % yield, drug entrapment efficiency, particle size, swelling index, mucoadhesion, and in-vitro drug release. The optimized microspheres were incorporated into an in-situ nasal gel and characterized for pH, gel strength, viscosity, and mucoadhesive force. Results: The microspheres exhibited % yield of 58.9–77.0%, drug entrapment efficiency of 48.6–72.3%, particle sizes of 16.2–35.0 µm, swelling indices of 22.5– 56.2%, and mucoadhesion of 45.2–75.6%. Invitro release studies showed sustained drug release over 8 hours, with the optimized gel displaying suitable pH (6.0–6.3), gel strength, viscosity, and mucoadhesive force, ensuring compatibility with nasal mucosa. Conclusion: The study demonstrates that Chlorpheniramine maleate-loaded mucoadhesive microspheres incorporated into in-situ nasal gels are a promising approach for sustained intranasal drug delivery, offering enhanced residence time, improved bioavailability, and reduced systemic side effects.