Development of solidified self-microemulsifying drug delivery systems containing l-tetrahydropalmatine: Design of experiment approach and bioavailability comparison

Publication date: 15 February 2018 Source:International Journal of Pharmaceutics, Volume 537, Issues 1–2 Author(s): Nguyen-Thach Tung, Cao-Son Tran, Thi-Minh-Hue Pham, Hoang-Anh Nguyen, Tran-Linh Nguyen, Sang-Cheol Chi, Dinh-Duc Nguyen, Thi-Bich-Huong Bui The study first aimed to apply a design of experiment (DoE) approach to investigate the influences of excipients on the properties of liquid self-microemulsifying drug delivery system (SMEDDS) and SMEDDS loaded in the pellet (pellet-SMEDDS) containing l-tetrahydropalmatine (l-THP). Another aim of the study was to compare the bioavailability of l-THP suspension, liquid SMEDDS and pellet-SMEDDS in the rabbit model. By using Central Composite Face design (CCF), the optimum ratio of Capryol 90, and Smix `(Cremophor RH 40: Transcutol HP) in the formulation of SMEDDS was determined. This optimum SMEDDS was absorbed on the solid carrier (Avicel or Aerosil) for the preparation of pellet-SMEDDS by extrusion and spheronization method. The ANOVA table indicated that Avicel was more effective than Aerosil, the traditional solid carrier, in both terms of preservation of dissolution rate of l-THP from the original SMEDDS and pelletization yield. Results obtained from scanning electron microscopy (SEM) indicated that the existence of liquid SMEDDS droplets on the surface of pellet-SMEDDS was due to the absorption on Avicel. The powder X-ray diffractometry proved the amorphous state of l-THP in pellet-SMEDDS. Pharmacokinetic stu...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research