Skin permeability and transdermal delivery route of 30-nm cyclosporin A - loaded nanoparticles using PLGA-PEG-PLGA triblock copolymer

The aim of this study was to investigate the skin permeability of a hydrophobic drug when using poly( DL -lactide- co -glycolide)-block-poly(ethylene glycol)-block-poly( DL -lactide- co -glycolide) triblock copolymers (PLGA-PEG- PLGA) as a drug carrier. Two types of PLGA-PEG-PLGA nanoparticles with an average particle size of 30 nm and poly( DL -lactide- co -glycolide) (PLGA) nanoparticles for comparison were prepared using a combination of an antisolvent di ffusion method with preferential solvation. Cyclosporin A was used as a hydrophobic model drug. From the results of the in vitro release test, it was con firmed that the release of the drug from the nanoparticles was relatively fast in the PLGA-PEG-PLGA nanoparticles. This result suggested that, compared to PLGA nano - particles, the thermodynamic activity of PLGA-PEG-PLGA nanoparticles increased and the di ffusion of the drug into the stratum corneum was promoted. The results of studies on skin permeability using rat skin and a transdermal delivery route showed that PLGA-PEG-PLGA nanoparticles were useful for e fficient drug skin per- meation and can deliver the drugs deep into the epidermal and dermal layers. Additionally, in the membrane permeability tests using Strat-M ?, which imitates human skin, the membrane permeation amount of the drug was signi ficantly increased when PLGA-PEG-PLGA nanoparticles were used compared with when PLGA nano - particles were used.