Low-Temperature Plasmas for Medicine?

302

225

Over the past decades, a new branch of plasma research, the nanomaterial (NM) synthesis by plasma-liquid interactions (PLIs), is rapidly rising, mainly due to the recently developed various plasma sources operated from low to atmospheric pressures. The PLIs provide novel plasma-liquid interfaces where many physical and chemical processes take place. By exploiting these physical and chemical processes, various NMs ranging from noble metal nanoparticles to graphene nanosheets can be easily synthesized. The currently rapid development and increasingly wide utilization of the PLI method naturally lead to an urgent requirement for presenting a general review. This paper reviews the current status of research on plasma-liquid 2 interactions for nanomaterial syntheses. Focus is on the comprehensive understanding of the synthesis process and perceptive opinions on the present issues and future challenges in this subject.

Section: Physical and Chemical Processes In Plasma-liquid Interactionsmentioning

confidence: 99%

A review of plasma–liquid interactions for nanomaterial synthesis

Chen¹,

Li²,

Li³

2015

302

225

“…Hence, they are widely used in a broad spectrum of applications ranging from low temperature plasma chemistry, decomposition of gaseous pollutants, light sources, surface modification to medical sterilization and microbial decontamination (Kogelschatz, 2004;Becker et al, 2005;Foest et al, 2005;Ehlbeck et al, 2008). But also emerging application areas like plasma healthcare can be approachable by the usage of non-LTE plasmas (Stoffels, 2007;Kong et al, 2009;Lloyd et al, 2010;Laroussi, 2009;Fridman et al, 2008). Thus, plasma treatment of cancer cells (Kim, Kim, Park, Jeon, Seo, Iza and Lee, 2009;Vandamme et al, 2010;Zhang et al, 2008), living human cells (Tümmel et al, 2007;Stoffels et al, 2008;Yonson et al, 2006), prevention of nosocomial infections and the therapy of infected wounds (Fridman et al, 2008;Isbary et al, 2010) as a few examples are in the ongoing research focus.…”

Section: Plasma Classificationmentioning

confidence: 99%

Low temperature atmospheric pressure plasma sources for microbial decontamination

Ehlbeck¹,

Schnabel²,

Polák³

et al. 2010

635

415

To cite this version:J EhlbeckAbstract. The aim of this article is to provide a survey of plasma sources at atmospheric pressure used for microbicidal treatment. In order to consider the interdisciplinary character of this topic an introduction and definition of basic terms and procedures is given for plasma as well as for microbicidal issues. The list of plasma sources makes no claim to be complete, but to represent the main principles of plasma generation at atmospheric pressure and to give an example of their microbicidal efficiency. The interpretation of the microbicidal results remain difficult due to the non standardized methods uses by different authors and due to the fact that small variations in the set up can change the results dramatically.

“…Applications stemming from the interactions of plasmas and liquids include biomedicine and biological disinfection [3][4][5][6][7][8], chemical disinfection [9][10][11], and agricultural uses [12,13]. To most effectively utilize plasma-liquid systems requires a fundamental knowledge of their behavior; many researchers are now actively contributing to that knowledge through both experimental [1][2][14][15][16][17][18][19] and modelling efforts [20][21][22][23].…”

Section: Introductionmentioning

confidence: 99%

Fully coupled simulation of the plasma liquid interface and interfacial coefficient effects

Lindsay¹,

Graves²,

Shannon³

2016

There is a growing interest in the study of coupled plasma-liquid systems because of their applications to biomedicine, biological and chemical disinfection, agriculture, and other areas. Optimizing these applications requires a fundamental understanding of the coupling between phases. Though much progress has been made in this regard, there is still more to be done. One area that requires more research is the transport of electrons across the plasma-liquid interface. Some pioneering works (Rumbach et al 2015 Nat. Commun. 6, Rumbach et al 2015 J. Phys. D: Appl. Phys. 48 424001) have begun revealing the near-surface liquid characteristics of electrons. However, there has been little work to determine the near-surface gas phase electron characteristics. Without an understanding of the near-surface gas dynamics, modellers are left to make assumptions about the interfacial conditions. For instance it is commonly assumed that the surface loss or sticking coefficient of gas-phase electrons at the interface is equal to 1. In this work we explore the consequences of this assumption and introduce a couple of ways to think about the electron interfacial condition. In one set of simulations we impose a kinetic condition with varying surface loss coefficient on the gas phase interfacial electrons. In a second set of simulations we introduce a Henry's law like condition at the interface in which the gas-phase electron concentration is assumed to be in thermodynamic equilibrium with the liquid-phase electron concentration. It is shown that for a range of electron Henry coefficients spanning a range of known hydrophilic specie Henry coefficients, the gas phase electron density in the anode can vary by orders of magnitude. Varying reflection of electrons by the interface also has consequences for the electron energy profile; increasing reflection may lead to increasing thermalization of electrons depending on choices about the electron energy boundary condition. This variation in anode electron density and energy as a function of the interface characteristics could also lead to significant variation in near-surface gas chemistries when such reactions are included in the model; this could very well in turn affect the reactive species impinging on the liquid surface. We draw the conclusion that in order to make more confident model predictions about plasma-liquid systems, finer scale simulations and/or new experimental techniques must be used to elucidate the near-surface gas phase electron dynamics.