Design and Development of Saxagliptin Microparticles for Diabetes

This study investigates the design, development, and evaluation of sustained-release Saxagliptin microparticles, utilizing Eudragit L-100 and Eudragit S-100 as polymers to achieve prolonged drug release. A total of eight formulations were prepared, employing varying drug-to-polymer ratios (1:1, 1:2, 1:3, and 1:4) for both core and coat materials. This approach facilitated an assessment of the concentration of coating material influenced the drug release rate. The solvent evaporation method proved effective in producing discrete, spherical microparticles characterized by good flowability and minimal stickiness. The surfactant Span 80 was optimized at a concentration of 1.0% to ensure optimal emulsion stability and microparticle formation. Results demonstrated that Eudragit S-100 based microparticles exhibited a significantly slower drug release profile compared to those formulated with Eudragit L-100. Notably, the formulation with a 1:4 Saxagliptin-to-Eudragit S-100 ratio achieved sustained release for up to 12 hours, confirming the trend of decreasing release rates with increasing concentrations of coating material. Dissolution data analysis revealed that the release kinetics best fit a zero-order model, indicating a constant drug release rate over time. Furthermore, the Peppas model provided the most suitable framework for understanding the drug release mechanism. The exponential coefficient (n) values indicated a non-Fickian release pattern, signifying a complex interplay between diffusion and erosion processes, which are critical for maintaining the sustained-release profile. Additionally, FTIR spectroscopy was employed to assess the compatibility of Saxagliptin within the optimized formulation. The results confirmed that the drug retained its chemical identity, with no evidence of chemical interactions between Saxagliptin and the excipients. This comprehensive study underscores the potential of Eudragit S-100 as an effective polymer for developing sustained-release formulations of Saxagliptin, enhancing patient compliance and therapeutic outcomes.