ABSTRACT:
Floating drug delivery system (microsphere) promises to be a potential approach for gastric retention. The present study was designed to formulate floating microsphere of tramadol hydrochloride by using enteric polymer such as acrycoat S 100 to improve the release profile of the drug and also target it to stomach and upper intestine via gastric retention. The microspheres were prepared by non-aqueous emulsification solvent evaporation technique. A 32 factorial design was used to elucidate the effect of variable viz. amount of drug and the amount of polymer. Non-aqueous emulsification solvent evaporation technique resulted in floating microsphere with good yield and moderate entrapment. The prepared floating microsphere sizes were in the range of 241.12 ± 8.4 to 421.42 ± 12.4 µm. These floating microspheres of tramadol hydrochloride were capable of floating on simulated gastric fluid for more than 12 hour. The amount of polymer affected the particle size and drug release. As the polymer concentration increases the particle size increases and drug release decreases.