A new perspective in understanding the dissolution behavior of nifedipine controlled release tablets by NIR spectroscopy with aquaphotomics

Abstract

The in vitro dissolution profile is a key parameter which reflects the quality of sustained-release tablets. Most studies were used to determine the dissolution of tablets utilizing dissolution curves. This study aimed to investigate the role of water during nifedipine controlled release tablets dissolution process in order to provide a new way to understand the dissolution behavior. Dissolution liquid was added to the drug-containing layer slowly, and near infrared spectra were acquired according to the set time. NIR spectroscopy with aquaphotomics were introduced to determine different water patterns. The results showed that, the structural change of water was consistent with the dissolution process. During hydration stage, it was mainly Sr combined with the semi-permeable membrane to form a channel. Then S0, S1, S2 and S3 combined with the drug layer and the push layer. Finally, it was relied on the swelling of the push layer to push the drug layer out at the release process. This study not only deepens the understanding of the dissolution process, but also opens a new perspective in molecular interaction analysis in aqueous system by understanding the roles of water.