Center for Innovation Competence Plasmatis

Greifswald, Germany

Center for Innovation Competence Plasmatis

Greifswald, Germany
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Iseni S.,Center for Innovation Competence Plasmatis | Iseni S.,Leibniz Institute for Plasma Science and Technology | Zhang S.,TU Eindhoven | Van Gessel A.F.H.,TU Eindhoven | And 7 more authors.
New Journal of Physics | Year: 2014

The effluent of an RF argon atmospheric pressure plasma jet, the so-called kinpen, is investigated with focus on the nitric-oxide (NO) distribution for laminar and turbulent flow regimes. An additional dry air gas curtain is applied around the plasma effluent to prevent interaction with the ambient humid air. By means of laser-induced fluorescence (LIF) the absolute spatially resolved NO density is measured as well as the rotational temperature and the air concentration. While in the laminar case, the transport of NO is attributed to thermal diffusion; in the turbulent case, turbulent mixing is responsible for air diffusion. Additionally, measurements with a molecular beam mass-spectrometer (MBMS) absolutely calibrated for NO are performed and compared with the LIF measurements. Discrepancies are explained by the contribution of the NO2 and N2O to the MBMS NO signal. Finally, the effect of a conductive substrate in front of the plasma jet on the spatial distribution of NO and air diffusion is also investigated.


Fricke K.,Leibniz Institute for Plasma Science and Technology | Koban I.,University of Greifswald | Tresp H.,Leibniz Institute for Plasma Science and Technology | Tresp H.,Center for Innovation Competence Plasmatis | And 6 more authors.
PLoS ONE | Year: 2012

Introduction: The medical use of non-thermal physical plasmas is intensively investigated for sterilization and surface modification of biomedical materials. A further promising application is the removal or etching of organic substances, e.g., biofilms, from surfaces, because remnants of biofilms after conventional cleaning procedures are capable to entertain inflammatory processes in the adjacent tissues. In general, contamination of surfaces by micro-organisms is a major source of problems in health care. Especially biofilms are the most common type of microbial growth in the human body and therefore, the complete removal of pathogens is mandatory for the prevention of inflammatory infiltrate. Physical plasmas offer a huge potential to inactivate micro-organisms and to remove organic materials through plasma-generated highly reactive agents. Method: In this study a Candida albicans biofilm, formed on polystyrene (PS) wafers, as a prototypic biofilm was used to verify the etching capability of the atmospheric pressure plasma jet operating with two different process gases (argon and argon/oxygen mixture). The capability of plasma-assisted biofilm removal was assessed by microscopic imaging. Results: The Candida albicans biofilm, with a thickness of 10 to 20 μm, was removed within 300 s plasma treatment when oxygen was added to the argon gas discharge, whereas argon plasma alone was practically not sufficient in biofilm removal. The impact of plasma etching on biofilms is localized due to the limited presence of reactive plasma species validated by optical emission spectroscopy. © 2012 Fricke et al.


Gaens W.V.,University of Antwerp | Iseni S.,Center for Innovation Competence Plasmatis | Iseni S.,Leibniz Institute for Plasma Science and Technology | Schmidt-Bleker A.,Center for Innovation Competence Plasmatis | And 5 more authors.
New Journal of Physics | Year: 2015

In this paper we study the cold atmospheric pressure plasma jet, called kinpen, operating in Ar with different admixture fractions up to1%pureN2,O2 and N2+O2. Moreover, the device is operating with a gas curtain of dry air. The absolute net production rates of the biologically active ozone (O3) and nitrogen dioxide (NO2) species are measured in the far effluent by quantum cascade laser absorption spectroscopy in the mid-infrared. Additionally, a zero-dimensional semi-empirical reaction kinetics model is used to calculate the net production rates of these reactive molecules, which are compared to the experimental data. The latter model is applied throughout the entire plasma jet, starting already within the device itself. Very good qualitative and even quantitative agreement between the calculated and measured data is demonstrated. The numerical model thus yields very useful information about the chemical pathways of both the O3 and theNO2 generation. It is shown that the production of these species can be manipulated by up to one order of magnitude by varying the amount of admixture or the admixture type, since this affects the electron kinetics significantly at these low concentration levels. © 2015 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.


Schnabel U.,Leibniz Institute for Plasma Science and Technology | Schnabel U.,Center for Innovation Competence Plasmatis | Niquet R.,Leibniz Institute for Plasma Science and Technology | Krohmann U.,Leibniz Institute for Plasma Science and Technology | And 4 more authors.
Plasma Processes and Polymers | Year: 2012

Gentle sanitation of fresh fruits and vegetables is highly demanded. Currently used methods lead to losses in product amounts and quality. Furthermore, these methods go along with high costs and chemical residues. One reason for such problems is microbial contamination. Due to the fact that conventional decontamination processes are not suitable for preservation of fresh produce, alternatives such as plasma technology can be helpful. Three different artificial specimen and seeds of Brassica napus were contaminated with endospores of Bacillus atrophaeus and afterwards plasma treated directly with DBD plasma and indirectly with microwave plasma processed air. After a treatment time of 15 minutes reduction rates between 0.5 and 5.2 log were achieved. The viability of seeds was not affected. The advantages of plasma and promising results offer a wide range of possible uses in food industry. The antimicrobial efficacy of a dielectric barrier discharge (DBD) and a microwave plasma setup against Bacillus atrophaeus spores on biological and non-biological surfaces is investigated. Moreover, the establishment of a non-biological specimen for the comparability of different plasma techniques is shown. The decontamination efficiency raised up to 5.2 log cfu/specimen by plasma treatment. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


von Woedtke T.,INP Greifswald e.V | Reuter S.,INP Greifswald e.V | Reuter S.,Center for Innovation Competence Plasmatis | Masur K.,INP Greifswald e.V | And 2 more authors.
Physics Reports | Year: 2013

Plasma medicine is an innovative and emerging field combining plasma physics, life science and clinical medicine. In a more general perspective, medical application of physical plasma can be subdivided into two principal approaches. (i) "Indirect" use of plasma-based or plasma-supplemented techniques to treat surfaces, materials or devices to realize specific qualities for subsequent special medical applications, and (ii) application of physical plasma on or in the human (or animal) body to realize therapeutic effects based on direct interaction of plasma with living tissue. The field of plasma applications for the treatment of medical materials or devices is intensively researched and partially well established for several years. However, plasma medicine in the sense of its actual definition as a new field of research focuses on the use of plasma technology in the treatment of living cells, tissues, and organs. Therefore, the aim of the new research field of plasma medicine is the exploitation of a much more differentiated interaction of specific plasma components with specific structural as well as functional elements or functionalities of living cells. This interaction can possibly lead either to stimulation or inhibition of cellular function and be finally used for therapeutic purposes. During recent years a broad spectrum of different plasma sources with various names dedicated for biomedical applications has been reported. So far, research activities were mainly focused on barrier discharges and plasma jets working at atmospheric pressure. Most efforts to realize plasma application directly on or in the human (or animal) body for medical purposes is concentrated on the broad field of dermatology including wound healing, but also includes cancer treatment, endoscopy, or dentistry.Despite the fact that the field of plasma medicine is very young and until now mostly in an empirical stage of development yet, there are first indicators of its enormous economic potential. This ambivalent situation fundamentally requires a responsible use of plasma sources, which are specifically designated for biomedical applications. To enable physicians as well as life scientists to decide whether a given plasma source is really suitable for medical applications or biological experiments, a meaningful and mandatory spectrum of indicators has to be compiled to allow for a basic estimation of the potential of this plasma source. © 2013 Elsevier B.V.


Weltmann K.-D.,Leibniz Institute for Plasma Science and Technology | Polak M.,Leibniz Institute for Plasma Science and Technology | Masur K.,Leibniz Institute for Plasma Science and Technology | Masur K.,Center for Innovation Competence plasmatis | And 5 more authors.
Contributions to Plasma Physics | Year: 2012

The use of plasma for healthcare can be dated back as far as the middle of the 19th century. Only the development of room temperature atmospheric pressure plasma sources in the past decade, however, has opened the new and fast growing interdisciplinary research field of plasma medicine. Three main topics can be distinguished: plasma treated implants, plasma decontamination, and plasmas in medical therapy. Understanding of the plasma sources and the plasma processes involved is still incomplete. With the aim of a more fundamental insight we investigate plasmas in a) functionalization of implants with antimicrobial as well as cell attachment enhancing surfaces b) atmospheric pressure plasmas (APPs) in inactivation of bacteria, decontamination of bottles and food products, as well as medical equipment and c) APPs in medical therapy and their effects on cell viability as a means to finding a plasma "dosage". The possibilities of an application focused designing of plasma sources will be emphasized. On the example of feed gas humidity and its significant influence the importance of determining and controlling unobvious or hidden parameter is demonstrated. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Winter J.,Center for Innovation Competence Plasmatis | Winter J.,Leibniz Institute for Plasma Science and Technology | Brandenburg R.,Leibniz Institute for Plasma Science and Technology | Weltmann K.-D.,Leibniz Institute for Plasma Science and Technology
Plasma Sources Science and Technology | Year: 2015

Atmospheric pressure plasma jets have a long history of more than 50 years. During this time their design and plasma generation mechanism has been developed and adapted to various fields of applications. This review aims at giving an overview of jet devices by starting with a brief history of their development. This is followed by an overview of commonly used terms and definitions as well as a survey of different classification schemes (e.g. geometry, excition frequency or specific energy input) described in literature. A selective update of new designs and novel research achievments on atmospheric pressure plasma jets published in 2012 or later shows the impressive variety and rapid development of the field. Finally, a brief outlook on the future trends and directions is given. © 2015 IOP Publishing Ltd.


Reuter S.,Center for Innovation Competence Plasmatis | Schmidt-Bleker A.,Center for Innovation Competence Plasmatis | Iseni S.,Center for Innovation Competence Plasmatis | Winter J.,Center for Innovation Competence Plasmatis | Weltmann K.-D.,Leibniz Institute for Plasma Science and Technology
IEEE Transactions on Plasma Science | Year: 2014

Formerly so-called bullet jets have been in the focus of atmospheric pressure plasma jet research of the past years. In this paper, two perspectives of the dynamic phenomenon are presented. Averaged, the dynamics appears as a bright spot-the so-called bullet-traveling from the plasma jet nozzle. In single shot it is revealed that the discharge mode in fact is a streamer-type discharge leaving the jet nozzle into the ambient. © 2014 IEEE.


Iseni S.,Center for Innovation Competence Plasmatis | Reuter S.,Center for Innovation Competence Plasmatis | Schmidt-Bleker A.,Center for Innovation Competence Plasmatis | Weltmann K.-D.,Leibniz Institute for Plasma Science and Technology
IEEE Transactions on Plasma Science | Year: 2014

In this paper, a megahertz atmospheric pressure plasma jet is investigated regarding its discharge pattern in correlation with the flow. Single-shot imaging shows plasma streamer development in a flow pattern determined by turbulent interaction with the atmosphere. Planar laser-induced fluorescence imaging on hydroxyl shows the flow pattern. The discharge pattern is streamerlike. Here, it can be observed that the streamer exhibits a hook-like structure at the end, which might also be attributed to the gas flow pattern. © 2014 IEEE.


Pipa A.V.,Leibniz Institute for Plasma Science and Technology | Reuter S.,Leibniz Institute for Plasma Science and Technology | Reuter S.,Center for Innovation Competence Plasmatis | Foest R.,Leibniz Institute for Plasma Science and Technology | Weltmann K.-D.,Leibniz Institute for Plasma Science and Technology
Journal of Physics D: Applied Physics | Year: 2012

The production of NO radicals by an atmospheric pressure plasma jet has been investigated by means of absorption spectroscopy in the mid-infrared region (IR) and optical emission spectroscopy (OES) in the ultraviolet (UV) part of the spectrum. The plasma jet investigated here operates in argon with air admixtures up to 1%. The study shows that OES can be used to characterize the relative NO production at small air admixtures. The Production of NO radicals can be controlled by variation of air admixture. Important to noteespecially for operation in ambient conditionsis that a small addition of water vapour strongly affects the production of NO radicals especially at higher air admixtures (greater than 0.2%). © 2012 IOP Publishing Ltd.

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