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Pharmaceuticals and cosmetics for dermal application are usually tested on healthy skin, although the primary permeation barrier, the stratum corneum, is often impaired by skin diseases or small skin lesions, especially on the hands. These skin conditions can considerably influence the permeation of chemicals and drugs. Furthermore, risk assessment for example of nanoparticles should be performed under various skin conditions to reflect the true circumstances. Therefore, an alternative and reproducible method for a high throughput of skin samples with impaired skin barrier was developed and verified by skin permeation studies (25 h) of caffeine, sorbic acid and testosterone compared to healthy (untreated) and tape-stripped skin. Skin barrier disruption was controlled by TEWL measurement.Skin permeation of the three substances was increased in tape-stripped and abraded skin compared to untreated skin due to the reduced barrier integrity. Enhancement of drug uptake was highest for the most hydrophilic substance, caffeine, followed by sorbic acid and lipophilic testosterone. No significant difference in drug uptake studies was observed between the new abrasion method with an aluminum-coated sponge and the tape-stripping method. The obtained results demonstrate that this abrasion method is an alternative way to achieve a disturbed skin barrier for drug and chemical uptake studies.

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In the last years indoor positioning is getting more and more important for industrial and commercial usage. Progressive approaches are developed to use leaky coaxial cables (LCX) not only for radio coverage but also for indoor navigation, too. Here latest results of the WIPoS project are shown, which focus on indoor positioning based on LCX measurements applying RF fingerprinting. With RF fingerprinting the received signal power levels are measured at equidistant positions and are stored in a radio map. An increase of the localization accuracy is achievable by reducing the power level fluctuations measured at the LCX cable ends, which were used for RF fingerprinting. Several averaging algorithms like averaging by time, place, antenna orientation, RF channel bandwidth and combinations of them had been applied for smoothing the power level fluctuations. But the achievable improvement on the indoor positioning accuracy was still insufficient for practical applications. Therefore the different effects leading to receive power fluctuations had been extracted and are explained in this paper. Based on these investigations the results of the first LCX prototype are presented.