P. Ramasubramaniyan

Glipizide is oral hypoglycemic agent, used for treatment of type II diabetes mellitus. Glipizide is insoluble in water. To increase the solubility, dissolution rate and bioavailability of glipizide it must be made its a suitable formulation by incorporating with suitable hydrophilic carriers. Such formulation provides a means of reducing particle size to nearly a molecular level. solid dispersion technique was adapted to enhance the solubility and dissolution rate of glipizide by incorporating hydrophilic carrier such as  Polyvinylpyrrolidone  K30 (PVP-K30) in different ratios were used . The formulation of the solid dispersion were carried our by preparing the  physical mixtures of glipizide using the Polyvinylpyrrolidone  K30 (PVP-K30) in four  different ratios.(1:2, 1:4, 1:6 and 1:8).Characterization of solid dispersions and physical mixtures were confirmed by Determination of Drug content, Solubility study, Thermal study, I R Spectral Analysis, Differential Thermal Analysis (DSC) and Powder x-ray Diffraction Analysis (XRD).From the results it was concluded that the Glipizide : polyvinylpyrrolidone  K30 The dissolution study showed that a maximum increase in dissolution rate was obtained with glipizide: PVP K-30 solid dispersions with a higher ratio of (1:8).

In vitro-invivo correlation plays a key role in pharmaceutical development of dosage form, optimization of formulation. This articles describes about the regulatory criteria and the factors associated with developing an In-vitro and in-vivo correlation. This factors plays an important role in optimizing the design and protocol required fort development of any dosage form and to identify the bioavailability pattern of the dosage forms. This article provide information on the various guidelines, factors in developing the correlations, bio pharmaceutical classification system,and other applications.