Application of polymers in promoting transdermal absorption

Transdermal drug delivery system (TDDS) can avoid the first-pass effect of the liver, and increase the compliance of patients, and the application of transdermal administration is safe and convenient. However, many drugs are not easily absorbed through the skin because of barrier function. Thus, promoting the transdermal absorption of drug is essential. Polymers, which are formed by repeating units as a basic structure, can promote transdermal absorption as a chemical penetration promoter or as a raw material for micro needles and nanosystems. This article first briefly introduces the structure and properties of the skin and the way drugs are absorbed through the skin, and then classifies polymers that can promote transdermal absorption in accordance with their electrical charge and mechanism of drug transdermal absorption promotion. The mechanism of promoting transdermal absorption of drug through the skin is also introduced to provide ideas for the application of polymers in promoting the penetration of drugs through the skin.