Polyoxazolines are a new promising class of polymers for biomedical applications. Antibiofouling polyoxazoline coatings can suppress bacterial colonization of medical devices, which can cause infections to patients. However, the creation of oxazoline-based films using conventional methods is difficult. This study presents a new way to produce plasma polymerized oxazoline-based films with antibiofouling properties and good biocompatibility. The films were created via plasma deposition from 2-methyl-2-oxazoline vapors in nitrogen atmospheric pressure dielectric barrier discharge. Diverse film properties were achieved by increasing the substrate temperature at the deposition. The physical and chemical properties of plasma polymerized polyoxazoline films were studied by SEM, EDX, FTIR, AFM, depth-sensing indentation technique, and surface energy measurement. After tuning of the deposition parameters, films with a capacity to resist bacterial biofilm formation were achieved. Deposited films also promote cell viability.

A recently presented novel plasma source generating discharge in liquids based on the pin-hole discharge configuration is characterized in detail. The system is supplied by DC non-pulsing high voltage of both polarities in NaCl water solutions at a conductivity range of 100-15 000 μS/cm. The discharge itself shows self-pulsing operation. The discharge ignition is observed in micro bubbles by transient discharge followed by a glow discharge in positive polarity at lower conductivities propagating inside the bubbles. At high conductivities, the glow regime is particularly replaced by a more energetic sequence of transient discharges followed by a shorter glow mode operation. The transient regime probability and its intensity are higher in the negative discharge polarity. The transient discharge produces acoustic waves and shock waves, which are observed at the moment of the bubble cavitation. The average gas temperature of 700-1500 K was calculated from the lowest OH (A-X) 0-0 band transitions. The average electron concentrations of 10 20 -10 23 m −3 were calculated from H α and H β line profiles. Finally, the production of a chemically active species is determined by hydrogen peroxide energy yields related to the energy consumption of the whole interelectrode system. All these quantities are dependent on the solution conductivity, the discharge polarity, and the applied power.

Polyoxazoline thin coatings were deposited on glass substrates using atmospheric pressure plasma polymerization from 2-ethyl-2-oxazoline vapours. The plasma polymerization was performed in dielectric barrier discharge burning in nitrogen at atmospheric pressure. The thin films stable in aqueous environments were obtained at the deposition with increased substrate temperature, which was changed from 20 ∘C to 150 ∘C. The thin film deposited samples were highly active against both S. aureus and E. coli strains in general. The chemical composition of polyoxazoline films was studied by FTIR and XPS, the mechanical properties of films were studied by depth sensing indentation technique and by scratch tests. The film surface properties were studied by AFM and by surface energy measurement. After tuning the deposition parameters (i.e., monomer flow rate and substrate temperature), stable films, which resist bacterial biofilm formation and have cell-repellent properties, were achieved. Such antibiofouling polyoxazoline thin films can have many potential biomedical applications.

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This work extends our previous experimental studies of the chemistry of Titan's atmosphere by atmospheric glow discharge. The Titan's atmosphere seems to be similarly to early Earth atmospheric composition. The exploration of Titan atmosphere was initiated by the exciting results of the Cassini-Huygens mission and obtained results increased the interest about prebiotic atmospheres. Present work is devoted to the role of CO in the prebiotic atmosphere chemistry. Most of the laboratory studies of such atmosphere were focused on the chemistry of N + CH mixtures. The present work is devoted to the study of the oxygenated volatile species in prebiotic atmosphere, specifically CO reactivity. CO was introduced to the standard N + CH mixture at different mixing ratio up to 5 % CH and 3 % CO. The reaction products were characterized by FTIR spectroscopy. This work shows that CO modifies the composition of the gas phase with the detection of oxygenated compounds: CO and others oxides. There is a strong influence of CO on increasing concentration other products as cyanide (HCN) and ammonia (NH).

Atmospheric pressure dielectric barrier discharge (DBD) in Ar/H2 gas feed with C2H2 or CH4 admixture was studied at room and high temperature of 680 °C by plasma diagnostics (electrical measurements, fast camera imaging, and optical emission spectroscopy). It was shown that filamentary DBD in pure Ar or Ar/H2 can be converted into homogeneous discharge by an acetylene admixture. Fast intensified charge-coupled device (ICCD) camera proved that this homogeneous discharge is an atmospheric pressure glow discharge (APGD) at room temperature whereas at high temperature the discharge mode switches at every half-period between APGD and atmospheric pressure Townsend discharge. The high temperature discharges (610–710 °C) in Ar/H2/C2H2 and Ar/H2/CH4 were also investigated with respect to a surface bound deposition of carbon nanotubes using 5 nm thick iron layer as a catalyst. CNTs were deposited without any dedicated catalyst pretreatment phase. The quality of CNTs, namely, their density, vertical alignment, and width of the diameter distribution, was better for the C2H2 gas feed and higher temperatures.

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In this paper, we report presence of various organic products formed in a flowing atmospheric glow discharge fed by gas mixture containing 1‐5 % of methane in nitrogen, which mimics the Titan's atmosphere. Gaseous products from the discharge exhaust were analysed by Gas Chromatography with Mass Spectrometry (GC‐MS). The experimental results revealed C2H2, HCN, and CH3CN as the major products. Various hydrocarbons and nitriles were the other determined gaseous products. Whilst many of these compounds have been predicted and/or observed in the Titan atmosphere, the present plasma experiments provide evidence of both the chemical complexity of Titan atmospheric processes and the mechanisms by which larger species grow prior to form the dust that should cover much of the Titan's surface. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)