Ambient air particle transport into the effluent of a cold atmospheric-pressure argon plasma jet investigated by molecular beam mass spectrometry

Ambient air species, which are transported into the active effluent of an atmospheric-pressure plasma jet result in highly reactive oxygen and nitrogen species (RONS). Especially for the envisaged application field of plasma medicine, these RONS are responsible for strong biological responses. In this work, the effect of ambient air transport into the effluent of an atmospheric-pressure plasma argon jet on the on-axis densities of nitrogen, oxygen and argon was investigated by means of absolutely calibrated molecular beam mass spectrometry (MBMS). According to biomedical experiments a (bottomless) Petri dish was installed in front of the MBMS. In the following, the near flow field is referring to the region close to the nozzle exit and the far flow field is referring to the region beyond that. The absolute on-axis densities were obtained by three different methods, for the near flow field with VUV-absorption technique, for the far flow field with the MBMS and the total flow field was calculated with a computational fluid dynamics (CFD) simulation. The results of the ambient air particle densities of all independent methods were compared and showed an excellent agreement. Therefore the transport processes of ambient air species can be measured for the whole effluent of an atmospheric-pressure plasma jet. Additionally, with the validation of the simulation it is possible in future to calculate the ambient species transport for various gas fluxes in the same turbulent flow regime. Comparing the on-axis densities obtained with an ignited and with a non-ignited plasma jet shows that for the investigated parameters, the main influence on the ambient air species transport is due to the increased temperature in the case when the jet is switched on. Moreover, the presence of positive ions (e.g. ) formed due to the interaction of plasma-produced particles and ambient air species, which are transported into the effluent, is shown.

[1]  L. Pitchford,et al.  Influence of a plasma jet on the hydrodynamics of a helium jet , 2013 .

[2]  Z. Petrović,et al.  Detection of atomic oxygen and nitrogen created in a radio-frequency-driven micro-scale atmospheric pressure plasma jet using mass spectrometry , 2012 .

[3]  Walter R. Lempert,et al.  Laser Rayleigh scattering , 2001 .

[4]  P. Sharma,et al.  Species enrichment due to Mach‐number focusing in a molecular‐beam mass‐spectrometer sampling system , 1976 .

[5]  Z. Petrović,et al.  Mass analysis of an atmospheric pressure plasma needle discharge , 2010 .

[6]  P. J. Hendra,et al.  Laser Raman spectroscopy. A review , 1970 .

[7]  I. Yimer,et al.  Estimation of the turbulent Schmidt number from experimental profiles of axial velocity and concentration for high-reynolds-number jet flows , 2002 .

[8]  K. Weltmann,et al.  From RONS to ROS: Tailoring Plasma Jet Treatment of Skin Cells , 2012, IEEE Transactions on Plasma Science.

[9]  J. Byun,et al.  Atmospheric-pressure plasma sources for biomedical applications , 2012 .

[10]  Gregor E. Morfill,et al.  Plasma medicine: an introductory review , 2009 .

[11]  P. Bruggeman,et al.  Laser scattering on an atmospheric pressure plasma jet: disentangling Rayleigh, Raman and Thomson scattering , 2012 .

[12]  E. L. Knuth,et al.  Composition distortion in MBMS sampling , 1995 .

[13]  A. Castleman,et al.  Thermal energy reactions involving Ar+ monomer and dimer with N2, H2, Xe, and Kr , 1987 .

[14]  K. Weltmann,et al.  Atomic oxygen in a cold argon plasma jet: TALIF spectroscopy in ambient air with modelling and measurements of ambient species diffusion , 2012 .

[15]  David H. Smith,et al.  Analysis of solution residues by glow discharge mass spectrometry , 1993, Journal of the American Society for Mass Spectrometry.

[16]  G. Millot,et al.  Accurate spectroscopic constants of nitrogen determined from stimulated Raman spectra of the fundamental and first hot bands , 1990 .

[17]  P. Bruggeman,et al.  Mass spectrometry study of positive and negative ions in a capacitively coupled atmospheric pressure RF excited glow discharge in He–water mixtures , 2010 .

[18]  T. von Woedtke,et al.  Atmospheric-pressure plasma sources: Prospective tools for plasma medicine , 2010 .

[19]  Y. A. Gonzalvo,et al.  Atmospheric pressure plasma analysis by modulated molecular beam mass spectrometry , 2006 .

[20]  Mounir Laroussi,et al.  Low Temperature Plasma-Based Sterilization: Overview and State-of-the-Art , 2005 .

[21]  A. Boccara,et al.  A common path interferometer for testing the optical thickness of possibly birefringent transparent substrates , 2001 .

[22]  N. Bibinov,et al.  Characterization of transient discharges under atmospheric-pressure conditions applying nitrogen photoemission and current measurements , 2011, 1109.5620.

[23]  Jörg Ehlbeck,et al.  Antimicrobial treatment of heat sensitive products by miniaturized atmospheric pressure plasma jets (APPJs) , 2008 .

[24]  Ronny Brandenburg,et al.  Atmospheric Pressure Plasma Jet for Medical Therapy: Plasma Parameters and Risk Estimation , 2009 .

[25]  K. Weltmann,et al.  Feed gas humidity: a vital parameter affecting a cold atmospheric-pressure plasma jet and plasma-treated human skin cells , 2013 .

[26]  J. Benedikt,et al.  Unexpected O and O3 production in the effluent of He/O2 microplasma jets emanating into ambient air , 2012 .

[27]  George S. Springer,et al.  Engine emissions : pollutant formation and measurement , 1973 .

[28]  J. Benedikt,et al.  Quadrupole mass spectrometry of reactive plasmas , 2012 .

[29]  E. Knuth.  Direct-Sampling Studies of Combustion Processes , 1973 .

[30]  D. Uhrlandt,et al.  Transport mechanisms of metastable and resonance atoms in a gas discharge plasma , 2013 .

[31]  P. Bruggeman,et al.  Electron properties and air mixing in radio frequency driven argon plasma jets at atmospheric pressure , 2013 .

[32]  Klaus-Dieter Weltmann,et al.  Basic requirements for plasma sources in medicine , 2011 .

[33]  P. Bruggeman,et al.  Mechanisms of bacterial inactivation in the liquid phase induced by a remote RF cold atmospheric pressure plasma jet , 2013 .

[34]  J. Benedikt,et al.  Characterization of the effluent of a He/O2 microscale atmospheric pressure plasma jet by quantitative molecular beam mass spectrometry , 2010 .

[35]  Eva Stoffels,et al.  A plasma needle generates nitric oxide , 2006 .

[36]  Klaus-Dieter Weltmann,et al.  Controlling the Ambient Air Affected Reactive Species Composition in the Effluent of an Argon Plasma Jet , 2012, IEEE Transactions on Plasma Science.