In Vitro Topographical Characterization as a Predictor of in Vivo Controlled Release Quinidine Gluconate Bioavailability

Abstract

The pH dissolution profiles and bioavailability data of six quinidine gluconate controlled release products were obtained, and attempts were made to identify a dissolution condition that is most indicative of in vivo bioavailability. This was achieved by graphically displaying the pH dissolution profiles of the six products in multi-dimensional graphs utilizing a topographical plotting technique. These graphs were found to be quite effective in illustrating: a) the effects of pH and buffer composition on the dissolution rate of the test products, and b) the in vitro condition that best correlates with in vivo data. It was found that for the quinidine gluconate controlled release dosage forms studied, dissolution carried out in pH 5.4 phosphate buffer was most meaningful in showing the differences among dosage forms and for predicting in vivo bioavailability