Comparison of Nifedipine/Polyvinylpyrrolidone Amorphous Solid Dispersions Miscibility at Various Temperatures

Abstract

The miscibility of Nifedipine/Polyvinylpyrrolidone (NIF/PVP) amorphous solid dispersions (ASDs) is crucial for predicting crystallization resistance and stability. This study evaluates the effectiveness of rheological and solid-state nuclear magnetic resonance (ssNMR) methods for determining miscibility at different temperatures. Specifically, it examines whether rheological methods are reliable at high temperatures (175°C) and ssNMR at low temperatures (-20°C), their consistency in results, the impact of molecular weight on miscibility, and the implications for stability prediction. Experimental data confirm that rheological analysis provides accurate miscibility assessment at elevated temperatures, while ssNMR is precise at lower temperatures. The findings demonstrate consistency between these methods, establish molecular weight as a significant factor in miscibility determination, and highlight the importance of accurate miscibility measurement for predicting ASD stability. These insights contribute to improving methodologies for evaluating ASD stability, addressing existing research gaps, and enhancing pharmaceutical formulation strategies.