Paper of the week: Hydroxypropyl-β-cyclodextrin-grafted polyethyleneimine used as a transdermal penetration enhancer
05 Aug 2014
‘The stratum corneum (SC) of skin is the main barrier against transdermal drug penetration, and poor permeability in the SC limits the usefulness of the transdermal drug administration route. Generally, drug permeation through the SC could be increased with skin permeation enhancers. Currently, enhancers most frequently used in transdermal drug delivery systems are neatly divided into three categories. One is organic solvents such as ethanol, propylene glycol and dimethyl sulfoxide. The second is surfactants such as cationic, anionic and nonionic surfactants. The last category is laurocapram and its derivative series. Nevertheless, their potential shortcomings have gradually been recognized, for their great irritation to skin or causing harm to organs. The practical use of enhancers requires the careful balancing of skin toxicity and permeation enhancement benefits’
In this work, Xing and co-workers developed a new penetration enhancer based on hydroxypropyl-β-cyclodextrin-grafted polyethyleneimine (HP-β-CD–PEI). Its penetration mechanism relied on a change of the secondary structure of keratin in the stratum corneum to enhance the transcutaneous permeation of drugs. By using a series of in vitro and in vivo methods, this cationic polymer demonstrated great biocompatibility and could be valuable for topical delivery as a penetration enhancer to improve the penetration of hydrophilic drugs.
In vitro and in vivo application of hydroxypropyl-β-cyclodextrin-grafted polyethyleneimine used as a transdermal penetration enhancer by Ke Wang, Yan Yan, Guilan Zhao, Wei Xu, Kai Dong, Cuiyu You, Lu Zhang and Jianfeng Xing, Polym. Chem. 2014, 5, 4658-4669.
Julien Nicolas is a web-writer and advisory board member for Polymer Chemistry. He currently works at Univ. Paris-Sud (FR) as a CNRS researcher.