In present study valacyclovir, microsphere was prepared by ionic gelation technique. Valacyclovir HCl, having a short biological half-life of < 30 minutes (Acyclovir 1.5-2 h) and its rapid elimination from the body, is ideally suited to be delivered through floating multiunit dosage form. Six formulations with natural polymers were formulated and characterized for their micromeritic and other properties. The process induced the formation of microspheres with the incorporation efficiency of 98% to 99%. The effect of sodium alginate and xanthan gum concentration and conditions were evaluated with respect to entrapment efficiency, particle size, buoyancy studies, surface characteristics and in vitro release behaviours. The infrared spectroscopic study confirmed the absence of any drug-polymer interaction. Microsphere matrices showing spherical surface, which was confirmed by scanning electron microscopy study. The mean particle size and entrapment efficiency were found to be varied by changing various formulation parameters. The in vitro release profile could be altered significantly by changing various formulation parameters to give a prolonged release of drug from the microspheres.
