Plasma Induced Changes in Human Lipid Composition as Revealed through XPS-Analysis

Abstract

In this study two plasma sources were used for an in vivo treatment of human stratum corneum. The sample preparation was realised with the Cyanoacrylat stripping method, whereby a few layers of corneocytes embedded in the lipid matrix were removed from the skin of healthy volunteers. For the plasma treatment, dielectric barrier discharges with pulse durations in the microsecond as well as in the nanosecond range were applied. A comparison of these sources with respect to their biologically active components including dissipated power, gas and electron temperature, irradiance in the ultraviolet range, ozone and nitric oxide concentration is presented. Furthermore, species generated during plasma treatment on the sample surface like hydrogen peroxide, nitride or nitrate were measured using reflectometry. In addition, safety aspects for both sources were evaluated. Resulting plasma induced changes in the sample composition were investigated through X-ray photoelectron spectroscopy. The main ingredients carbon, oxygen, and nitrogen in addition to minor concentrations of sulphur were considered. A significant influence of the pulse duration on plasma characteristics was shown. A more effective formation of reactive species as well as more intense UV emission for ns-plasma was observed. Based on the determined parameters, both plasma sources are suitable for therapeutic purpose. Furthermore, significant plasma induced changes in the stratum corneum composition were reported, including an increase in nitrogen and oxygen content.

Transdermal administration of adenosine using microplasma and the examination of the effect of microplasma on stratum corneum using infrared spectroscopy

“…Lipids exposed to plasma are degraded. Studies by Marschewski et al 10) and Hirschberg et al 11) showed that plasma exposure raised the oxygen and nitrogen atom concentration in skin lipids.…”

Effect of microplasma treatment on stratum corneum lipid molecule

“…Plasma discharge is capable of creating many reactive particles. Investigation of the interaction of the air plasma with the skin lipids was presented by Marchewski et al 12) and Hirschberg et al 13) These works showed that the plasma-treated lipids increased the concentration of oxygen and nitrogen atoms in the samples, suggesting oxidation and nitration of the lipids or lipid removal. Molecular dynamics simulation of OH and O radical reaction with α-linolenic acids (non-saturated fatty acid) demonstrated the creation of double bonds, alcohol or aldehyde formation.…”

Evaluation Strategies for Risk Assessment and Usability of Medical Plasma Sources in Dermatology

“…Furthermore, with another but very similar DBD and a related setup, sample heating was analyzed. This revealed that one minute of plasma treatment only marginally increased sample temperatures [160]. Hence, no thermal injury is to be expected from applications with the µs-pulsed DBD.…”

“…The calculation of the effective irradiance produced by the kINPen ® MED was based on measurements with a calibrated optic spectrometer system [138]. The spectral irradiance of the µs-pulsed DBD plasma was calculated after detection of the irradiance with a calibrated radiometer [160]. The results showed that no radiation in the UVC region (200-280 nm) was generated by either of the two APP devices [47,138].…”