Background: Application of cold atmospheric pressure plasmas (CAPs) in or on the human body was termed ‘plasma medicine'. So far, plasmas were utilized for sterilization of implants, other heat-sensitive products, or employed for chemical surface modifications. By now, CAPs are further used effectively for wound treatment. The present study analyses the effect of a plasma jet with air or nitrogen as process gas, previously evaluated for antimicrobial efficacy, on human cells using a 3D skin model. Methods: CAP treatment of 3D skin models consisting of a keratinocyte-containing epidermal layer and a fibroblast/collagen dermal matrix was performed using the Tigres plasma MEF technology. To evaluate the effects on the 3D skin models, the following plasma parameters were varied: process gas, input power, and treatment time. Results: Low CAP doses exhibited good cell compatibility. Increasing input power or elongating treatment intervals led to detrimental effects on 3D skin model morphology as well as to release of inflammatory cytokines. It was further observed that air as process gas was more damaging compared to nitrogen. Conclusions: Treatment of 3D skin models with the plasma MEF nozzle using air or nitrogen is reported. A clearly dose- and time-dependent effect of CAPs could be observed in which the CAP based on nitrogen exhibited higher cell compatibility than the CAP generated from air. These settings might be recommended for medical in vivo applications such as wound decontamination.

Long chain starch esters were prepared by a new method using molten imidazole as solvent for the biopolymer. The advantage is the simplicity of the reaction mixture. Imidazole is acting not only as solvent, but also as reagent and base. The reaction succeeds via the imidazolide, which is formed in situ with an acid chloride. It yields highly pure derivatives, as could be shown by NMR spectroscopy and elemental analysis. No hints for desoxychloro substituents or other impurities could be found. The high quality of the products prepared is responsible for the occurrence of colorless melts. Although DSC measurements show a variety of thermal transitions, the formation of melts in the range of 40 to 255 °C could be observed with a hot stage microscope. The melting behavior can be adjusted by the type of ester moiety and the amount of ester functions introduced. In case of starch palmitates completely transparent melts are obtained within two distinct DS regions namely around 1.5 and 2.2 to 3.0. Upon cooling the melts form homogeneous films on different supports including glass. They show good adhesion and should therefore be a suitable basic material for the preparation of composites like laminated glass.

Complexes [M(O2CCH2OC2H4OMe)2] (M = Co, Mn) were synthesized characterised regarding their thermal behaviour. They were used as precursors for deposition of rough Co3O4and smooth Mn2O3/Mn3O4thin filmsviathe CCVD process.

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Beech and larch substrates were successfully treated by an atmospheric pressure plasma jet (APPJ) or a diffuse coplanar surface barrier discharge (DCSBD) system. Applying both technologies on wood, more hydrophilic properties were achieved, potentially by the degradation of hydrophobic extractives, the generation of polar functional groups and a modification of surface roughness. Comparing both plasma systems, the hydrophilization effect was stronger using the APPJ. The formation of polar groups on the surface was detected by X–Ray photoelectron spectroscopy. Investigated by scanning electron microscopy, APPJ further showed a more distinct impact on surface morphology compared to DCSBD. Following natural aging, plasma treatment effects such as hydrophilicity were partially reduced and the recovery was more pronounced for larch wood compared to beech.