Article
Multidisciplinary Sciences
Hye Ran Lee, Yun Sang Lee, Young Suk You, Jin Young Huh, Kangil Kim, Yong Cheol Hong, Chul-Ho Kim
Summary: Skin antiseptics play a crucial role in public health and medicine. However, conventional antiseptics often come with skin toxicity and resistance development. This study demonstrates that plasma-activated water (PAW) generated by a microwave plasma system can serve as a novel antiseptic solution for skin protection. PAW exhibits excellent bactericidal effects without toxicity on normal skin cells. Furthermore, PAW shows potential as a sanitizer for SARS-CoV-2. These findings support the use of PAW as an effective and safe skin disinfectant in the current global pandemic.
SCIENTIFIC REPORTS
(2022)
Article
Pharmacology & Pharmacy
Zhijun Guo, Dan Sun, Xian Zhou, Huan Xu, Yizhou Huang, Chenglin Chu, Baolong Shen
Summary: In this study, a facile direct current atmospheric pressure micro-plasma (APM) technology was used for the first time to synthesize functional gold nanoparticle/chitosan (AuNP/CS) nanocomposites. The effects of experimental parameters on the resulting nanocomposite structures and properties were investigated. The results demonstrate that APM is a facile, rapid, and versatile technique for the synthesis of AuNP/CS functional nanocomposites.
Article
Physics, Fluids & Plasmas
Daniel C. Martin, David M. Bartels, Paul Rumbach, David B. Go
Summary: This study experimentally investigates the transport of solvated electrons injected into plasma using TIRAS, confirming a power law relationship between optical absorption intensity and current density. By controlling current density through ionic strength manipulation, different scaling behaviors were observed at varying concentrations, with implications for tailored plasma-liquid systems.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Analytical
Sebastian van Wasen, Yi You, Sebastian Beck, Jens Riedel, Dietrich A. Volmer
Summary: The combination of acoustically levitated droplets, mid-IR laser evaporation, and subsequent post-ionization by secondary electrospray ionization was used to monitor the enzymatic digestion of various proteins. Acoustically levitated droplets provide a wall-free model reactor for compartmentalized microfluidic trypsin digestions. Time-resolved interrogation of the droplets provides real-time information on the reaction progress and insights into reaction kinetics. Importantly, the experimental setup can be used for the real-time investigation of chemical reactions and uses only a fraction of the typically applied amounts of solvent, analyte, and trypsin, making it a green analytical chemistry alternative to batch reactions.
ANALYTICAL CHEMISTRY
(2023)
Article
Physics, Fluids & Plasmas
Shane Keniley, Necip B. Uner, Elizabeth Perez, R. Mohan Sankaran, Davide Curreli
Summary: This study presents a one-dimensional, time-dependent multi-physics model to analyze the gas-liquid phase combined chemical reactions at a plasma-liquid interface. Both experimental and modeling results show that the production of aqueous hydrogen peroxide is significantly higher during anodic operation.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Applied
Li Wu, Xianyu Zhang, Tao Liu, Wencong Zhang, Junwu Tao, Fei Cheng
Summary: This Letter presents an atmospheric pressure low power microwave-induced air plasma source operating at 2.45 GHz. The device can self-ignite air and generate plasma with only 50 W microwave input power, without any additional trigger. Its sustaining power is as low as 10 W, and the gas temperature of plasma tail flame is about 32 degrees C measured by a fiber optic thermometer. Spectroscopic measurements revealed the presence of strong OH(A(2)S(+)? X-2?) bands at 306-310 nm and oxygen atomic lines O-I (3p5P? 3s5S) at 777.1 nm and O-I (3p3P?3s3S) at 844.6 nm. Furthermore, NO- ?(A(2)S(+)?X-2?(r)) from 200 to 300 nm was also detected in the air plasma jet. This portable plasma apparatus shows potential for air plasma applications in the biomedical fields.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Applied
Eric Timmermann, Robert Bansemer, Torsten Gerling, Veronika Hahn, Klaus-Dieter Weltmann, Stefan Nettesheim, Markus Puff
Summary: The piezoelectric-driven plasma pen investigated in this study shows a high potential for medical application due to its distinct antimicrobial efficacy. The antimicrobial efficacy differs not only between the piezoelectric plasma pen and the argon-fed medical plasma source, but also between the different nozzles of the piezoelectric plasma pen. The physical properties measured at the determined operating parameters do not pose any human health risks.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2021)
Article
Physics, Applied
Naoki Shirai, Takuma Kaneko, Yuto Takamura, Koichi Sasaki
Summary: Measuring surface tension is an effective method for real-time examination of the plasma-liquid interface. The variation in surface tension is correlated with the behavior of OH radicals in the gas phase.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Nanoscience & Nanotechnology
Fan Lei, Yan Xue, Donglin Liu
Summary: This study presents a simulation and calculation of a millimeter-scale microwave plasma generator (MPG) using COMSOL Multiphysics software. The model investigates the discharge behavior and physical characteristics of the MPG, including the electron density, temperature, and chemical composition. The results are informative for understanding the performance of the MPG and its potential application in small plasma capsules for cancer therapy.
Article
Engineering, Chemical
J. A. Silsby, S. Simon, J. L. Walsh, M. I. Hasan
Summary: A global computational model was developed to track the concentrations of aqueous reactive species in plasma activated water, comparing one-film and two-film theories in modeling the transport of reactive species across the gas-liquid interface, with the two-film theory showing better representation of certain ions.
PLASMA CHEMISTRY AND PLASMA PROCESSING
(2021)
Article
Physics, Fluids & Plasmas
Kaishu Nitta, Hitoshi Muneoka, Yoshiki Shimizu, Hiromichi Kobayashi, Kazuo Terashima, Tsuyohito Ito
Summary: Atmospheric-pressure nonequilibrium plasma processing using microdroplets has garnered attention in recent years. Understanding the evaporation behavior of droplets in plasma is crucial for improving process controllability. This study investigates the evaporation of controlled inkjet droplets in atmospheric-pressure nonequilibrium argon plasma through experiments and modeling. Comparing the droplet evaporation model, which considers gas temperature, electron and ion collisions, and recombination reactions, with experimental results, it is found that droplet evaporation is enhanced in high-density plasma with electron and ion densities exceeding 10(19) m(-3) compared to non-ionized gaseous environments at gas temperatures under 1000 K.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Jacob Manzi, Ariel E. E. Weltner, Tony Varghese, Nicholas McKibben, Mia Busuladzic-Begic, David Estrada, Harish Subbaraman
Summary: This paper demonstrates the use of plasma-jet printing (PJP) to deposit thermoelectric nanoflakes onto flexible substrates at room temperature, with substantial improvements in material adhesion and flexibility observed. The printed films exhibit electrical conductivity of 2.5 x 10(3) S m(-1) and a power factor of 70 mu W m(-1) K-2 at room temperature. This advancement in plasma jet printing promotes not only the development of energy harvesting but also large-scale flexible electronics and sensors for space and commercial applications.
Article
Chemistry, Multidisciplinary
Abd H. Babikir, Mihiri G. M. Ekanayake, Olawale Oloye, James D. Riches, Kostya (Ken) Ostrikov, Anthony P. O'Mullane
Summary: This study reports a method for rapidly converting CO2 into solid carbon using dispersed liquid metal Ga and dielectric barrier discharge (DBD) plasma. The research found that highly dispersed sub-nano-sized carbon particles containing oxygen functional groups were formed after the plasma treatment. Further analysis demonstrated that plasma electrons activate CO2 molecules, while plasma-generated oxygen vacancies on the catalyst surface help dissociate CO2 into solid carbon. This work opens a new approach for synthesizing highly dispersed sub-nano-sized carbon materials suitable for various applications such as adsorption, heterogeneous catalysis, and energy conversion.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Hannah L. Wapshott-Stehli, Brayden G. Myers, Maria J. Herrera Quesada, Amy Grunden, Katharina Stapelmann
Summary: Enzymes like OleT(JE) are commonly used in the industry, but the presence of hydrogen peroxide can cause overoxidation. This study explores the use of an atmospheric pressure plasma jet to generate hydrogen peroxide slowly in situ, providing a reliable reaction mediator for OleT(JE) activity.
PLASMA PROCESSES AND POLYMERS
(2022)
Article
Physics, Applied
Nanya Zhong, Gang Fu, Junjun Li, Chen Lian, Wenqi Chen, Kama Huang
Summary: A novel two-dimensional atmospheric pressure plasma jet device is proposed and validated through analysis of plasma parameters and establishment of an experimental system.
PLASMA PROCESSES AND POLYMERS
(2022)
Review
Food Science & Technology
Andreas S. Katsigiannis, Danny L. Bayliss, James L. Walsh
Summary: Food and drink manufacturers prioritize food safety and are exploring cold atmospheric pressure plasma (CAP) as a potential technique for surface and equipment decontamination in food processing environments. However, current CAP research is still in its early stages and lacks cohesive information for easy comparison. Scaling CAP technology to meet industry needs is also a significant challenge.
COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY
(2022)
Review
Food Science & Technology
Anis Asyila Marzlan, Anis Shobirin Meor Hussin, Paula Bourke, Sonal Chaple, Soukaina Barroug, Belal J. Muhialdin
Summary: The poultry processing sector is looking for alternatives to enhance safety and extend the shelf life of poultry meat, and plant essential oils have shown potential. However, the low stability and oxidation of essential oils have limited their applications, and the emergence of active packaging incorporating essential oils has become a new solution. Critical factors for successful development of active packaging interventions include appropriate essential oil selection, polymer source selection, bioactivity, and minimum inhibition concentrations.
FOOD REVIEWS INTERNATIONAL
(2023)
Article
Physics, Applied
Benjamin Gilbart, Aaron Dickenson, James L. Walsh, Mohammad Hasan
Summary: This study investigates how the electrode width of a surface barrier discharge (SBD) array affects the deposited power, the induced flow, and the spatial distribution of reactive species delivered to a downstream sample. It is shown that decreasing electrode width increases the power density and intensifies the oscillatory flow. The study identifies and quantifies a transition between convection-driven and diffusion-driven delivery for different electrode widths and distances between SBDs and the treated surface, and links ripples in the delivered flux to convection-driven delivery.
PLASMA PROCESSES AND POLYMERS
(2022)
Article
Multidisciplinary Sciences
Elmar Slikboer, Olivier Guaitella, Enrique Garcia-Caurel, Ana Sobota
Summary: Electric field and surface charge measurements were used to study the dynamics in the plasma-surface interaction. It was found that the periodic charging is directly dependent on the pulse length regardless of the control potential. Uncontrolled floating potential surface prevents a sustained plasma plume. Imposed DC bias can lead to higher electric fields and surface charge. These findings have important implications for surface treatment applications.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Pedro Viegas, Elmar Slikboer, Zdenek Bonaventura, Enric Garcia-Caurel, Olivier Guaitella, Ana Sobota, Anne Bourdon
Summary: This study examines and compares positive and negative ionization waves (IWs) in pulsed plasma jets and demonstrates the existence of a surface charging memory effect. The memory effect directly impacts the dynamics of IWs, especially when using negative electric polarity.
SCIENTIFIC REPORTS
(2022)
Article
Physics, Fluids & Plasmas
Alexandra Brisset, Benjamin Harris, Aaron Dickenson, Kari Niemi, James Walsh, Erik Wagenaars
Summary: Control of plasma chemistry is crucial for atmospheric pressure plasma in various applications. This study investigates the effects of humidity on discharge development, electric field, and electron density through experiments and modeling, providing experimental data for verifying kinetic models of plasmas in controlled environments.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2022)
Article
Food Science & Technology
Sonal Chaple, Chaitanya Sarangapani, Shannon Dickson, Paula Bourke
Summary: Cold plasma technology is a non-thermal technology that can improve food quality and functionality. Treating wheat flour with cold plasma positively affects the expansion ratio, crust color, and water activity of bread. It also improves water absorption capacity, dough development time, and stability, as well as the gluten network and overall acceptance of the bread. Cold plasma treatment can provide an alternative to chemical additives in bread making and can be tailored for specific effects.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2023)
Article
Food Science & Technology
Arturo B. Soro, Sajad Shokri, Iolanda Nicolau-Lapena, Daniel Ekhlas, Catherine M. Burgess, Paul Whyte, Declan J. Bolton, Paula Bourke, Brijesh K. Tiwari
Summary: This review highlights the challenges of using UV-LED technology as a disinfection strategy in the food chain. It discusses the stress-related mechanisms induced by UV-LED exposure in microorganisms and their impact on food quality. The findings suggest that UV-LEDs can effectively inactivate foodborne pathogens and spoilage microorganisms, but more research is needed to evaluate their effectiveness in improving food safety and understand the potential consequences of UV-LED exposure in different microorganisms at various wavelengths. Moreover, attention should be given to the underlying mechanisms of quality changes induced by UV-LEDs.
TRENDS IN FOOD SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Fluids & Plasmas
Alexandra Brisset, Matthew Bieniek, Laurent Invernizzi, Mohammad Hasan, James Walsh, Kari Niemi, Erik Wagenaars
Summary: This study investigates the spatio-temporal distribution of O and H radicals in a 90 ns pulsed discharge in He + H2O gas. Experiment and 1D fluid modelling show good agreement for the densities of O and H radicals. O and H densities are found to be homogeneous along the discharge axis. O is mainly produced by direct dissociation of O2 by electron impact during the discharge, and by dissociative recombination of O2 (+) in the early afterglow. H follows a similar production process as O, but with a stronger initial production of O in the presence of higher concentrations of water vapor.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Oncology
Beatriz Pinheiro Lopes, Liam O'Neill, Paula Bourke, Daniela Boehm
Summary: This study investigates a new approach for treating brain cancer by combining a conventional cancer drug with plasma-activated water. The combined treatments were found to interfere with cell metabolism, increase cell death, and reduce long-term cell proliferation.
Article
Biochemical Research Methods
P. Roszkowska, A. Dickenson, J. E. Higham, T. L. Easun, J. L. Walsh, A. G. Slater
Summary: Non-thermal plasma (NTP) is a promising state of matter for chemical reactions, providing high densities of reactive species without the need for a catalyst at atmospheric pressure and moderate temperature. However, a better understanding of the complex interactions between NTP and liquids is needed for comprehensive use of NTP in reactions. This study details the construction of a microfluidic reactor and a corresponding batch setup for NTP chemical reactions in organic solvents, enabling controlled generation of NTP and inline data collection. The developed frameworks contribute to the potential applications of NTP in chemical synthesis.
Article
Chemistry, Analytical
Jaka Olenik, Vasyl Shvalya, Martina Modic, Jernej Ekar, Janez Kovac, Uros Cvelbar, James L. Walsh
Summary: Fourier transform infrared spectroscopy (FTIR) is commonly used to study gas-phase reactive oxygen and nitrogen species (RONS). However, the presence of interfering peaks in spectral data poses challenges. This study investigates the interaction between reactive oxygen and nitrogen species generated by a non-equilibrium air plasma and the metal halide windows of an FTIR gas cell, leading to the appearance of spurious absorption peaks. Various spectroscopic techniques were employed to determine the origin of these peaks and it was found that KBr exposed to plasma showed a lower fraction of bromine and the formation of NO3 nitrate group. The evolution of these absorption peaks affected the window transparency and was correlated with KNO3 formation, plasma power, and exposure time.
JOURNAL OF ANALYSIS AND TESTING
(2023)
Article
Physics, Fluids & Plasmas
Gagandeep Singh Matharoo, James L. Walsh
Summary: This study describes the design and characterization of a unique repetitive pulsed power source that generates low-temperature plasma at atmospheric pressure in contact with water. The generated plasma produces highly oxidizing chemical species that can degrade recalcitrant organic contamination. The system's electrical efficiency ranges from 37% to 49% depending on the pulse repetition rate.
IEEE TRANSACTIONS ON PLASMA SCIENCE
(2023)
