International journal of pharmaceutics

Dual roles of TPGS based microemulsion for tacrolimus: Enhancing the percutaneous delivery and anti-psoriatic efficacy.

PMID 28629978


In this study, we demonstrate for the first time the dual roles of Tocopheryl Polyethylene Glycol 1000 Succinate (TPGS) based microemulsion (ME) for tacrolimus (TAC) to enhance TAC percutaneous delivery and anti-psoriatic efficacy. The ME formulation was developed and optimized based on pseudo-ternary phase diagrams combined with in vitro permeation. The result of Fourier transform infrared spectroscopy (FTIR) demonstrated that TAC was completely solubilized in the TPGS-ME. In vitro permeation studies showed that TPGS-ME enhanced TAC permeation through and into the skin, and the enhanced deposition of TAC in the normal or psoriatic skin was further confirmed in vivo. The cellular uptake performed with HaCaT cells presented more pronounced uptake of TPGS-ME. Topical TAC-TPGS-ME treated imiquimod-induced psoriasis in mice more efficaciously than the commercial formulation of TAC (Protopic