Midede alıkonularak kontrollü salım yapan matriks tabletlerin hazırlanması ve karekterizasyonu

Gastroretentive dosage forms can remain in the gastric region forseveral hours and hence significantly prolong the gastric residence time ofdrugs. Prolonged gastric retention improves bioavailability and improvessolubility for drugs that are less soluble in a high pH environmentThe aim of this study were to develop a single unit, floating drugdelivery system and to study the effect of important formulation parameters onthe floating and drug release behavior of these systems. Floating tablets wereprepared by direct compression method using different types of colloidalsilicon dioxide as foam powder and HPMC as matrix forming polymer.Pioglitazone hydrochloride which has a good solubility in acidic medium wasincorporated into the formulation as a model drug.Physicochemical characteristics of pioglitazone were determinedby UV and FT-IR spectrums, differential scanning calorimetry and particle sizeanalysis. In vitro floating and dissolution studies were performed using thepaddle method in 0.1 N HCl medium. The properties of the gastroretentivetablets, such as floating time, lag time, density and dissolution profiles wereinvestigated. The effect of the density and surface area of the low density foampowders on the resulting floatability of the investigated tablets was foundimportant. The drug release patterns can effectively be adjusted by varyingsimple formulation parameters, such as the type and concentration of matrixforming polymer, tablet hardness and diameter of the tablets.In conclusion a single unit, floating drug delivery system has beendeveloped, which is based on low density foam powder and matrix -formingpolymer.Keywords: Gastroretentive dosage forms, floated tablets, pioglitazone, lowdensity foam powders, Aerosil