The Development of Self-nanoemulsifying Liquisolid Tablets to Improve the Dissolution of Simvastatin


The aim of this work was to develop self-nanoemulsifying liquisolid tablets (SNELT) to enhance the dissolution profile of poorly water-soluble simvastatin. SNELT present a unique technique of incorporating self-nanoemulsifying drug delivery systems (SNEDDS) into tablets. Optimized SNEDDS containing different oils, Cremophor® RH 40 (surfactant) and Transcutol® HP (co-surfactant), at different ratios, were used as liquid vehicles and loaded on carrier material, microcrystalline cellulose (MCC), and coating material, Cab-o-sil® H-5 (nanosize colloidal silicon dioxide) powders at different loading factors (Lf) and fixed excipient ratio (R = 20). The effect of using different carrier materials, granulated mannitol, crystalline mannitol, and maltodextrin with MCC at different ratios, and different coating materials, Aeroperl® 300 (granulated silicon dioxide) at different excipient ratios (R), was also emphasized. Liquisolid powders with acceptable flowability, compressibility, and tablet weight were compressed into tablets. Results revealed that powders with Lf = 0.2 possessed the most preferable properties to be tableted. SNELT with MCC and Cab-o-sil® H-5 were able to generate nanoemulsions and to enhance the cumulative percent of drug dissolved at 60 min significantly to reach up to 90%. Furthermore, using carrier material (granulated mannitol/MCC at ratio 3:1) enabled SNELT to disperse into nanoemulsion (Z-average = 25.7 nm) and improved the dissolution profile significantly to reach 99% at 60 min. Cab-o-sil® H-5 proved to be a better coating material compared to Aeroperl® 300. In conclusion, developed SNELT were promising in enhancing in vitro dissolution of simvastatin and excipients highly affect SNELT’s performance.