Formulation and in vivo evaluation of chlorhexidine buccal tablets prepared using drug loaded chitosan microspheres

This investigation deals with the development of buccal formulations (tablets) based on chitosan microspheres containing chlorhexidine
diacetate. The microparticles were prepared by a spray-drying technique, their morphological characteristics were studied by scanning
electron microscopy and the in vitro release behaviour was investigated in pH 7.0 USP buffer. Chlorhexidine in the chitosan microspheres
dissolves more quickly in vitro than does chlorhexidine powder. The anti-microbial activity of the microparticles was investigated as
minimum inhibitory concentration, minimum bacterial concentration and killing time. The loading of chlorhexidine into chitosan is able
to maintain or improve the anti-microbial activity of the drug. The improvement is particularly high against Candida albicans. This is
important for a formulation whose potential use is against buccal infections. Drug-empty microparticles have an anti-microbial activity due
to the polymer itself. Buccal tablets were prepared by direct compression of the microparticles with mannitol alone or with sodium alginate.
After their in vivo administration the determination of chlorhexidine in saliva showed the capacity of these formulations to give a prolonged
release of the drug in the buccal cavity.