Formulation and physicochemical characterization of buccoadhesive microspheres containing diclofenac sodium.

Purpose: The present study involves preparation and evaluation of diclofenac buccal-mucoadhesive microparticles for prolongation of buccal residence time.

Methods: The microparticles were prepared by modified double-emulsion dehydration method (O1/W/O2) using sodium carboxymethylcellulose (CMC-Na) as mucoadhesive polymer. Calcium chloride was used as a cross-linking agent. Buccal-mucoadhesive microparticles with different drug to polymers ratios were prepared and characterized by encapsulation efficiency, particle size, DSC (Differential Scanning Calormetric), flowability, degree of swelling, surface pH, mucoadhesive property and drug release studies.

Results: The best drug to polymer ratio in microparticles was 1:5 (F3) with CMC-Na. F1 microparticles showed loading efficiency 51.43% and mean particle size 1013.92 μm. The DSC showed stable character of drug in microparticles and revealed amorphous form. Microparticles had slower release than the commercial tablet (p50 min). Histopathological studies revealed no buccal mucosal damage.

Conclusion: It may be concluded that drug loaded buccal-mucoadhesive microparticles are a suitable delivery system for DS.