Effect of abrasion induced by a rotating brush on the skin permeation of solutes with varying physicochemical properties.

A transient reduction in the barrier nature of the skin can be a pre-requisite for successful (trans)dermal delivery of some drugs. The aim of this present study was to investigate and effect of a dermal abrading "rotating brush" device on percutaneous absorption and skin integrity. In vitro experiments were conducted using excised human epidermal membrane. The effect of device parameters (bristle type, treatment duration and applied pressure) on skin permeability of model solutes (methyl paraben, butyl paraben, caffeine, acyclovir and angiotensin II) with varying physicochemical properties was examined and compared to established methods of skin penetration enhancement (positive controls). The device parameter which was found to have the most marked effect on permeability of the compounds was bristle type. Profound changes (2- to 100-fold increase) were observed in the epidermal permeability of the hydrophilic penetrants (caffeine, acyclovir and angiotensin II), when the brush device was employed compared to positive controls (ethanol enhancement, delipidisation, iontophoresis and tape-stripping). Findings from this present study support the effectiveness of a rotating brush applied to the skin in enhancing epidermal permeability. Further optimization of operational parameters is required to exploit this simple and effective delivery device.