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 (L _f ) 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 L _f  = 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.