Determination of Polymer Effectiveness

Ionizable pharmaceutical compounds, especially weakly basic drugs, have pH dependent solubility and therefore are susceptible to supersaturation and precipitation when encountering pH changes in the gastrointestinal (GI) tract. Our previous study shows that two types of supersaturation behavior can be observed: type I compounds have short durations of supersaturation while type II compounds are able to maintain supersaturation for prolonged periods of time. The goal of this study is 1) to study the supersaturation behavior of a type I compound, dipyridamole, in the presence of polymers by Bjerrum plot, 2) to evaluate the effectiveness of polymers in maintaining supersaturation.