Fluorescent polymer nanoparticles for skin penetration and distribution
Date of Issue2017
School of Chemical and Biomedical Engineering
Using nanoparticulate systems for transdermal delivery has emerged as an increasingly important approach in targeted drug delivery. Such nanosystems are also expected to enhance transdermal transport of active molecules into and/or across the skin without causing any significant skin damage. However, the mechanism how the nanoengineering formulation assists the skin conveyance remains ambiguous. In this study, I report a onepot method to synthesize hydrophilic fluorescent PFODBT nanoparticles with high photostability, aqueous stability and cytocompatibility for ex vivo murine skin penetration. Confocal laser scanning microscopy and fluorescence microscopy were used for visualizing the penetration and distribution of the nanoparticles with diameters 30, 60 and 100 nm and different surface charges through the murine skin. The images reveal that this nanoparticulate system designed for ex vivo measurements preferentially accumulates in the follicles in a surface charge-dependent manner and this localization appears to have no exact relation to the particle size when size is smaller than 100 nm. Importantly, increased positive surface charges can noticeably improve the depth of penetration into the epidermis, down to the dermis and cannot be inhibited by the stratum corneum. Therefore, this study demonstrates a straightforward and advanced nanosystem to facilitate the permeation through the skin barrier and provide a promising application in cosmetics and topical drug delivery.