Bulletin of the American Physical Society
71st Annual Gaseous Electronics Conference
Volume 63, Number 10
Monday–Friday, November 5–9, 2018; Portland, Oregon
Session PR2: Plasmas for Biological and Medical Applications |
Hide Abstracts |
Chair: Michael Keidar, George Washington University Room: Oregon Convention Center A105 |
Thursday, November 8, 2018 9:30AM - 9:45AM |
PR2.00001: Experimental and theoretical study of cold atmospheric plasma jet interaction with metal and dielectric surfaces Irina Schweigert, Sergey Vagapov, Li Lin, Michael Keidar Recently cold atmospheric plasma jets are widely used in various applications in medicine, material surface treatment and agriculture. In this work, the dynamics of propagation of a cathode-directed streamer and its reflection from surface is studied in numerical simulations (2D fluid model, cylindrical symmetry) and in the experiments. The streamers induced by applying sinusoidal voltage to the powered electrode inside of dielectric tube and propagates to the direction of treated metal or dielectric surfaces. The streamer starts inside of a dielectric tube in pure helium and propagates over a helium jet and a mixture of gases (helium, nitrogen and oxygen). The distribution of molar fractions of gases are calculated with ANSYS Fluent software for helium supply of 13.5 sl/min and the tube radius of 0.23 cm. The experimental data on the speed of a streamer are in a good agreement with calculation results. The reflection of ionization wave from the surface is observed both in the experiment and in simulations. In simulations, it was found that the reflected ionization wave follows a channel produced by a primary streamer. The difference in streamer reflection scenario from dielectric and metal surfaces is analyzed. [Preview Abstract] |
Thursday, November 8, 2018 9:45AM - 10:00AM |
PR2.00002: In situ Measurements of Total Yield of Species Originating from Plasma Jets. Ek Adhikari, Vladimir Samara, Kemo Jammeh, Sylwia Ptasinska Plasma reactive species which are directly originated in an atmospheric pressure plasma jet (APPJ) and/or indirectly produced in the cell can drive a plethora of biochemical reactions. To quantify the total yield of these species under different experimental conditions, we developed in situ optical absorption technique and used ferrous sulfate (Fricke) solution in which species were detected under plasma irradiation. We observed that the total yield increased at higher plasma frequencies and voltages, but the yield per pulse decreased at higher frequencies, indicating the formation of plasma species with various lifetimes. We also performed calculations of yields for particular plasma species which can be produced during irradiation and suggested several scenarios to identify which species formed in APPJs can be the most probably to be involved in chemical reactions. Furthermore, we compared the trends in DNA damage with the yields of species produced in Fricke solution to obtain a better understanding of plasma species involved in DNA damage. [Preview Abstract] |
Thursday, November 8, 2018 10:00AM - 10:15AM |
PR2.00003: Surface dielectric barrier discharge on polymer substrate for tissue treatment Seunghoon Lee To improve the electrical stability and portability of surface dielectric barrier discharge (SDBD) devices, it is necessary to secure low voltage and low power operations of SDBD. We fabricated polymer SDBD devices using commercial polymer substrates such as polyimide, polyethylene terephthalate. Functional thin film coatings were adapted to protect the degradation of polymer substrate due to reactive oxygen radicals. And the optimization of the electrode structure was conducted to minimize displacement current flow and maximize dissipated power. Several types of electrode such as circular, rectangular, and hexagonal geometry were investigated for SDBD devices. The SDBD showed stable discharge at a low voltage of 2 kV or less, and a pulse frequency of 5-10 kHz. Design parameters of flexible SDBD devices for low voltage and low power operations will be presented. [Preview Abstract] |
Thursday, November 8, 2018 10:15AM - 10:30AM |
PR2.00004: Characterization of isolated and combined radical, photon, and ion effects of cold atmospheric plasmas on liquids Jan Benedikt, Kerstin Sgonina, Gert Willems, Mohamed Mokhtar Hefny, Beatrix Biskup, Judith Golda Atmospheric non-equilibrium plasmas are an effective source of reactivity since they generate large densities of reactive radicals, metastables, ions and high fluxes of (V)UV photons. Especially important for therapeutic applications in plasma medicine is the fact that several or all of these components and electric fields are acting at the same time, very often in a synergistic way. Especially important for the understanding plasma effects is to obtain absolute fluxes of all plasma components to the surface and to study their isolated or combined effects. In this contribution, the mass spectrometry for detection of neutral and ionized species and the windowless VUV spectroscopy for the plasma analysis of the atmospheric plasma jet, which serves as a reference in several plasma medicine studies will be discussed in detail. Additionally, the way in which in isolated or combined effects of plasma-generated radicals, photons and even ions can be studied will be presented. [Preview Abstract] |
Thursday, November 8, 2018 10:30AM - 10:45AM |
PR2.00005: Osmotic pressure on cell membranes in a saline interacting with weakly ionized plasma Mikhail Shneider, Mikhail Pekker In this talk attention is drawn to the importance of accounting for osmotic pressure when analyzing physiological effects on cellular structures in plasma medicine. The selective effect of a plasma jet on living cells in a physiological solution can be related to a change in the osmotic pressure difference across the cell membrane, as a result of the injection of additional long-lived solvated (hydrated) ions by the plasma. This, in turn, leads to a stretching or compression of the membrane, depending on the difference of total external and internal pressures. The selective effect of plasma on cells, observed in experiments, may be associated with the change in the mechanical properties of membranes (and thereby, a weakening of their protective properties). Corresponding estimates are given. Our work does not claim to have found the only reason, why weakly ionized non-equilibrium plasma leads to cell death, but has identified a potential further physical mechanism that has relevance in plasma induced biological effects.. 1. M. N. Shneider, M. Pekker, J. Appl. Phys. 123, 204701 (2018) [Preview Abstract] |
Thursday, November 8, 2018 10:45AM - 11:00AM |
PR2.00006: Plasma-functionalized solution: A potent antimicrobial agent for biomedical applications from antibacterial therapeutics to biomaterial surface engineering Joo Young Park, Sanghoo Park, Wonho Choe, Hae In Yong, Cheorun Jo, Kijung Kim Deadly diseases caused by pathogenic bacteria have increasingly victimized humans; thus, the importance of disinfection has increased in medicine as well as in food and agricultural industries. Plasma contains multiple bactericidal agents, including reactive species, charged particles, and photons, and their synergistic effects. In particular, the chemicals formed in aqueous solution during plasma exposure have the potential for high antibacterial activity against various bacterial infections. Here, we report the antibiotic potency of plasma-treated water (PTW). To illustrate the applicability of PTW for disinfecting biological substances, Escherichia coli, Samonella typhimurium, and Listeria monocytogenes biofilms were used. We sought to identify the chemical species in the PTW and investigate their separate effects on biofilm removal. Dielectric barrier discharge, which is operated in ambient air, was used to prepare the PTW and to treat the biofilm directly. The major species of PTW that led to the biofilm reduction were OH, H$_{\mathrm{2}}$O$_{\mathrm{2}}$, HNO$_{\mathrm{2}}$, and O$_{\mathrm{3}}$. H$_{\mathrm{2}}$O$_{\mathrm{2}}$ was the most influential species, while O$_{\mathrm{3}}$ and HNO$_{\mathrm{2}}$ also contributed. [Preview Abstract] |
Thursday, November 8, 2018 11:00AM - 11:15AM |
PR2.00007: Atmospheric pressure plasma modification and damage quantification of amino acids Harold McQuaid, Mark Tweedie, Davide Mariotti, Paul Maguire Modification of biological material via non-thermal plasmas is continuing to gain much attention, however the mechanisms behind the damage enhancement and cell selectivity of plasmas are far from complete. Cysteine, a key amino acid in proteins, has been previously used in plasma interaction studies due to its relatively simple analysis and suitability as a biological model$^{\mathrm{1}}$. Investigations into plasma interaction with cysteine are currently limited to DBD$^{\mathrm{1}}$, COST-jet and kINPen$^{\mathrm{2}}$, and less directly via a DC plasma jet$^{\mathrm{3}}$. In this study the plasma induced interactions with cysteine are investigated using a remote RF plasma source containing He-H$_{\mathrm{2}}$O and isolated from atmospheric impurities in order to observe effects with relatively simplified plasma chemistry. Using a droplet in plasma system$^{\mathrm{4}}$ cysteine is passed through the plasma for 100 \textmu s and exposed to a high flux of electrons, ions and radicals. To aid understanding of the chemistry involved, buffer and radical scavenger solutions were also added. The modification of cysteine via each treatment method is analysed using FTIR and Raman spectroscopy and differences between those previously published are detected and attributed to a change in the plasma induced chemistry. 1. Kogelheide, F. et al. (2016). 2. Lackmann, J. W. et al. (2018). 3. Yan, D. et al.~ (2015). 4. M Maguire, P. D. et al. (2015). [Preview Abstract] |
Thursday, November 8, 2018 11:15AM - 11:30AM |
PR2.00008: Chemical kinetics of the sterilization by peroxynitric acid (HOONO$_{\mathrm{2}})$ in plasma-treated water Katsuhisa Kitano, Satoshi Ikawa, Yoichi Nakashima, Yusuke Kawashima, Takashi Yokoyama, Atsushi Tani For the disinfection of human body, plasma-treated water (PTW) has unique characteristics. While many types of PTWs have been studied in plasma medicine, we found that PTW had strong bactericidal activity at acidic pH (the reduced-pH method) and its bactericidal activity could be kept by cryo-preservation. Although PTW contains many chemical components, key bactericidal component was confirmed to HOONO$_{\mathrm{2}}$ (PNA: peroxynitric acid) from the analysis of ion chromatography. Bactericidal activity of PNA has not been known so far. Based on chemical kinetics, several properties of PNA in PTW would be discussed. Since PNA is chemically synthesized efficiently if pH \textless 2, PNA in PTW would be formed only in the thin plasma-liquid interface layer where pH locally decreases during plasma irradiation. Lower temperature brought longer half-life of PTW bactericidal activity with first-order reaction. Activation energies of decomposition with PTW and chemical-synthesized PNA solution are almost same (110 kJ/mol). Bactericidal activity was proportional to PNA concentration in PTW (Chick-Watson law). Higher temperature brought higher bactericidal activity, and activation energies of the reaction with PNA and bacteria depend on kind of bacteria. This suggests that the reaction sites of bacteria depend on the type of bacteria. [Preview Abstract] |
Thursday, November 8, 2018 11:30AM - 11:45AM |
PR2.00009: Venus Flytrap as a Sensor of Plasma-Produced RONS Alexander Volkov, Kunning Xu, Vladimir Kolobov We have observed that the\textit{ Dionaea muscipula} Ellis can be activated by cold plasma jets without direct touching of plants by plasma. Remote activation of plants by room-temperature plasma has been achieved by directing plasma jets to a lobe, midrib, or cilia, which induced the trap morphing. The observed effects are attributed to reactive oxygen and nitrogen species (RONS), which are known to be generated by plasma jets injected into atmospheric air. RONS produced by cold plasma appear to be the primary reason of plasma-induced chemotropic activation of sensors and actuators in plants, which induce the trap closing, locking, and constricting in the \quad Venus Flytrap like stimulation of its mechanosensors \textit{in vivo}. We have confirmed that application of H$_{\mathrm{2}}$O$_{\mathrm{2}}$ or HNO$_{\mathrm{3\thinspace }}$aqueous$_{\mathrm{\thinspace }}$solutions to the midrib induces propagation of action potentials and closing the trap similar to plasma effects. Direct measurements of the electrical signaling produced by plasma activation of the plants was hindered by the plant's capturing of the strong electrical signals generated by plasma. [Preview Abstract] |
Thursday, November 8, 2018 11:45AM - 12:00PM |
PR2.00010: Modelling plasma-produced reactive species delivery and scaling via prostate biopsy needles for application in prostate cancer therapy Andrew R. Gibson, Sandra Schroeter, Timo Gans, Mark J. Kushner, Deborah O'Connell The potential of non-thermal plasmas in biomedicine for applications from wound healing to cancer therapy is well-established. Reactive oxygen and nitrogen species (RONS) are thought to be key, and therefore controlled delivery of defined concentrations of RONS is likely to be crucial for the success of these applications. Presented here is a numerical study, carried out using the 0-D plasma-chemical kinetics code, GlobalKin, of RONS delivery via prostate biopsy needles for applications in prostate cancer therapy. Temporal variations in species densities are converted to a spatial variation down the needle length assuming plug-flow. An experimentally validated He/H$_{\mathrm{2}}$O/O$_{\mathrm{2}}$ plasma-chemical reaction mechanism is employed to describe reactive species formation and consumption. Reactive species scaling is investigated with respect to needle radius and length, power deposition, gas flow rate and the content of H$_{\mathrm{2}}$O and O$_{\mathrm{2}}$ in the He feed gas. The gas velocity in the needle is found to be a crucial factor in determining the reactive species composition of the gas reaching the end of the needle by determining the residence time of the gas in the plasma and the afterglow. Therefore, the flow rate act as a simple control parameter for the reactivity of the gas in applications. [Preview Abstract] |
Thursday, November 8, 2018 12:00PM - 12:15PM |
PR2.00011: The effect of biological model on the penetration of RONS generated by plasma. XinPei Lu In this presentation, firstly, a tissueliquid model is utilized to measure the penetration of the long life time RONS and pH value in the receiving chamber after penetrating through the pig muscle tissue. Results show that the six different type of liquid (inorganic group: double distilled water, 1{\%} PBS, 0.9{\%} NaCl; organic group: 5{\%} glucose, 2{\%} serum and 10{\%} serum solution) in the receiving chamber have significant impact on the concentration of RONS after penetrating through the 500$\mu $m tissue slice And the RNS concentration in serum solution is much larger than in the other solutions presumably due to the plasma reacting with the amino acid and other protein. Besides, the concentration of reactive oxygen and nitrogen species (RONS) generated by a plasma jet penetrating into and through the skin tissue after plasma treatment are measured, and the effects of stratum corneum on the penetration of RONS are also investigated. It is found that the RONS generated by the plasma jet can penetrate through the skin and the penetration could be enhanced largely by stripping the stratum corneum. Further investigation found out that the typical ROS species can't even penetrate the mice skin no matter whether the stratum corneum layer is present or not, where the thickness of the skin is about 200-300$\mu $m, this result is very different from the experiments results from muscle tissue model and gelatin model [Preview Abstract] |
Thursday, November 8, 2018 12:15PM - 12:30PM |
PR2.00012: Plasma-aided removal of grape bud dormancy as an effective alternative to natural chilling Zaka-ul-Islam Mujahid, Habib Khemira, Taeib Tounekti Several fruit vines and trees shed their leaves in the early-fall and pass the winter season in a state of reduced physiological activity called dormancy. The dormant state is initiated due to the low temperatures in early-fall, and it is also released by winter low temperatures (chilling). If the chilling period is not sufficient, the budbreak is delayed and crop growth is reduced leading to spread out crop maturation and often lower yield. In mild winter regions growers are using toxic chemicals such as hydrogen cyanamide, to substitute the chilling deficiency. So far there is no environmentally friendly and effective method to substitute the natural chilling. In this work, we report a simple plasma treatment method to release the dormancy of grape buds. We have found that the plasma treatment provides an improvement of several growth parameters of grape buds including higher percentage of bud break, superior shoot vigor; similar or better than the natural chilling. The analysis of bud proline, catalase and Malondialdehyde~(MDA) indicate that the plasma treatment induces an oxidative stress in plants with some similarities and differences to the natural chilling and previously reported hydrogen cyanamide methods. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700