Objectives The aim of the study was determine the effect of magnetic film array technology on the skin permeation of urea.
Methods A 5% urea gel was applied to human epidermal membrane in vitro and human skin in vivo. Application of gel with magnetic film array and plastic occlusive film was compared with application of gel with a plastic occlusive film and non-magnetic film. In-vitro epidermal penetration was determined using a Franz-type diffusion system. In-vivo permeation and changes in epidermal properties were visualised by optical coherence tomography.
Key findings The mean cumulative permeation of urea over 2 h for magnetic film array application was 89.54 ± 7.34 μg/cm2 as compared with 20.83 ± 2.02 μg/cm2 for passive occluded application (mean ± SEM, n = 9/8), representing greater than 4-fold increase over the 2-h application time period. Administration of urea with the magnetic film array resulted in the lag time being reduced from 40.58 ± 3.98 to 21.13 ± 6.27 min (P < 0.02), while steady state flux increased from 0.24 ± 0.03 to 0.75 ± 0.06 μg/cm2 per min (P < 0.0001). Under active occlusion, the relative change in epidermal thickness as determined by optical coherence tomography increased by 16 and 11% at 30 and 60 min, respectively.
Conclusions Administration with a novel magnetic film array technology provided enhanced skin penetration of urea and increased epidermal hydration when compared with administration under an occlusive film only.