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In recent years, plasma surface treatment has seen tremendous breakthroughs, which have revolutionized both the field of material engineering and the procedures used to modify surfaces. This paper offers a thorough discussion of the most recent discoveries and developments that have been made in the field of plasma surface treatment. It investigates cutting-edge technologies, innovative plasma sources and sophisticated process control approaches, all of which have greatly improved the effectiveness and adaptability of the therapy. The research also explores how these breakthroughs solve earlier obstacles, provide new opportunities for industrial applications and pave the way for future developments in the area. Moreover, the study looks at how these advancements open the door for future developments in the sector. This study gives useful insights into the emerging landscape of plasma surface treatment and its potential influence on a variety of sectors by summarizing and assessing current research. These insights may be found in this paper. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD) plasma has several applications in different fields. One of these fundamental applications is medical usages, where various methods are employed to improve the plasma treatment process. The combination of different gases is one of the important strategies to improve the performance of plasma in treatment. In this paper, the optimized plasma parameters for one-dimensional radiofrequency discharge produced at low pressures in a helium gas combination is studied. In this research, the optimal combination of H2O and He is identified to attain the highest amount of reactive oxygen species (ROS). Considered mixture are 5, 10, 15 and 20 precent of H2O for one dimensional helium gas discharge. The results show that the parameters of the output plasma are highly dependent on the composition of the input gases. It is found that the greatest concentrations of H+, H+, Hes (excited helium), and OH densities are observed when the H2O percentage was at 10%. Moreover, the density distributions of various species and the temperatures of electrons are numerically calculated during the electrical discharge process. These findings provide useful knowledge on how to optimize plasma parameters for biomedical applications, which may lead to improved treatment results in several therapeutic areas. [ABSTRACT FROM AUTHOR]

Cancer remains one of the global leading causes of death and various vaccines have been developed over the years against it, including cell-based, nucleic acid-based, and viral-based cancer vaccines. Although many vaccines have been effective in in vivo and clinical studies and some have been FDA-approved, there are major limitations to overcome: (1) developing one universal vaccine for a specific cancer is difficult, as tumors with different antigens are different for different individuals, (2) the tumor antigens may be similar to the body's own antigens, and (3) there is the possibility of cancer recurrence. Therefore, developing personalized cancer vaccines with the ability to distinguish between the tumor and the body's antigens is indispensable. This paper provides a comprehensive review of different types of cancer vaccines and highlights important factors necessary for developing efficient cancer vaccines. Moreover, the application of other technologies in cancer therapy is discussed. Finally, several insights and conclusions are presented, such as the possibility of using cold plasma and cancer stem cells in developing future cancer vaccines, to tackle the major limitations in the cancer vaccine developmental process. [ABSTRACT FROM AUTHOR]

Field Line Resonances (FLRs) are a critical component in Earth's magnetospheric dynamics, associated with the transfer of energy between Ultra Low Frequency waves and local plasma populations. In this study we investigate how the polarisation of FLRs are impacted by cold plasma density distributions during geomagnetic storms. We present an analysis of Van Allen Probe A observations, where the spacecraft traversed a storm time plasmaspheric plume. We show that the polarisation of the FLR is significantly altered at the sharp azimuthal density gradient of the plume boundary, where the polarisation is intermediate with significant poloidal and toroidal components. These signatures are consistent with magnetohydrodynamic modeling results, providing the first observational evidence of a 3D FLR associated with a plume in Earth's magnetosphere. These results demonstrate the importance of cold plasma in controlling wave dynamics in the magnetosphere, and have important implications for wave‐particle interactions at a range of energies. Plain Language Summary: Earth's space environment is home to electrons and ions across a wide range of energies, trapped in the region by our global geomagnetic field. Energy can be transferred to and from the trapped particles through oscillations in the magnetic field, and these processes are responsible for the extreme energization of trapped electrons to hazardous levels for local spacecraft. In this paper we explore a type of magnetic field oscillation termed Field Line Resonances (FLRs): standing waves on a field line analogous to the oscillatory motion of guitar strings. We use spacecraft observations to show that the direction of the field line oscillations changes significantly depending on the density of the background plasma. The results confirm previous modeling work, and are the first observational evidence of 3D FLRs at a plume. The findings have important consequences for how FLRs transfer energy between the electrons and ions. Key Points: We present the first observational evidence of a 3D Field Line Resonance at the sharp density gradient of a plume edgeThe observed polarisation change confirms magnetohydrodynamic modeling results and predictions made by Elsden and Wright (2022)The presence of 3D Field Line Resonances during storm times has impacts for how Ultra Low Frequency waves couple and interact with local plasma [ABSTRACT FROM AUTHOR]

As an innovative technology in biological applications, cold plasma is widely used in oral treatment, tissue regeneration, wound healing, and cancer therapy, etc., because of the adjustable composition and temperature which allow the plasma to react with bio-objects safely. Reactive oxygen species (ROS) produced by cold plasma regulate cell activity in an intensity- and time-dependent manner. A low level of ROS produced by cold plasma treatment within the appropriate intensities and times promotes proliferation of skin-related cells and increases angiogenesis, which aid in the acceleration of the wound healing process, while a high level of ROS produced by cold plasma treatment performed at a high intensity or over a long period of time inhibits the proliferation of endothelial cells, keratinocytes, fibroblasts, and cancer cells. Moreover, cold plasma can regulate stem cell proliferation by changing niche interface and producing nitric oxide directly. However, the molecular mechanism of cold plasma regulating cell activity and its potential application in the field of animal husbandry remain unclear in the literature. Therefore, this paper reviews the effects and possible regulatory mechanisms of cold plasma on the activities of endothelial cells, keratinocytes, fibroblasts, stem cells, and cancer cells to provide a theoretical basis for the application of cold plasma to skin-wound healing and cancer therapy. In addition, cold plasma exposure at a high intensity or an extended time shows excellent performances in killing various microorganisms existing in the environment or on the surface of animal food, and preparing inactivated vaccines, while cold plasma treatment within the appropriate conditions improves chicken growth and reproductive capacity. This paper introduces the potential applications of cold plasma treatment in relation to animal-breeding environments, animal health, their growth and reproduction, and animal food processing and preservation, which are all beneficial to the practice of animal husbandry and guarantee good animal food safety results. [ABSTRACT FROM AUTHOR]

Meat quality is damaged by traditional technologies. Researchers devised a revolutionary technique called plasma technology to meet the requirement for an effective cold processing method. Cold plasma (CP) used for meats and its products decontamination and storability extension has shown to be highly successful. The influence of CP on meat quality is important to its acceptability as an alternative meat processing technology. CP treatments have had effects on the color, pH, lipid oxidation, and microbial quality of different meat products. CP treatment offers crucial benefits over traditional processing methods because of its design adaptability, non-thermal behavior, relatively inexpensive, and environmental friendliness. CP processing is currently in its infancy and requires further investigation in meat and meat products to achieve its best extent. This paper discusses the fundamentals of CP technology, its effects on the quality of meats such as color, pH value, lipid oxidation, and microbial quality, and future perspectives. [ABSTRACT FROM AUTHOR]

In this paper, core–shell structured (ZnSe) is prepared bio synthesis by cold plasma technique under atmospheric pressure with an exposure time of 3 min and a gas flow rate of 3 L/min. Films' structural characteristics and morphological characterization were investigated by X-ray diffractometer, atomic force microscopy (AFM) and scanning electron microscopy (FE-SEM). In addition, parameters like crystal size were calculated. Results showed XRD patterns exhibit structure of polycrystalline of preferential orientation (111) direction. SEM technique shows that the nanoparticles presented are spherical. AFM image verified film-formed spherical particles distribute uniformly. The antibacterial diffusion method property of these nanoparticles was performed against Gram-negative bacteria of Escherichia coli and Gram-positive bacteria of Staphylococcus aureus, showing good control of said bacteria. The maximum level of inhibition was found in coli form bacteria with an average inhibition zone diameter with S. aureus, implying an increasing trend with increasing/decreasing loading volume of NC volume. Therefore, these nanomaterials, which can be prepared in a simple and cost-effective way, may be suitable for new types of germicidal materials. [ABSTRACT FROM AUTHOR]

Abstract: The treatment of additive-free hand sheet paper samples with cold plasma was carried out and showed that cellulose can be chemically linked with reactive natural products, namely myrcene (My) and limonene (LM). Contact-angle measurement and X-ray photoelectron spectroscopy (XPS) were used to ascertain the occurrence of the grafting. Indeed, the contact-angle value of a drop of water deposited at the surface of paper increased from 30° for unmodified substrate to about 105 and 107°, for LM- and My-treated samples, respectively. In fact, LM- and My-treated surfaces were rendered totally apolar. Indeed, the polar contribution to the surface energy decreased from about 23 mJ/m2 for pristine samples to practically zero for treated ones. The treated surfaces displayed water-barrier properties; the penetration of the liquid was reduced significantly after LM and My treatments. The XPS spectra showed that the modification with LM and My gave rise to very significant change in the O/C ratio, as well as in the intensity of the C1 peak assigned to aliphatic carbon sequences. [Copyright &y& Elsevier]

Healthy foods with fresh-like appearances are nowadays demanded by consumers. To satisfy these requirements, the research has been focused on unconventional non-thermal technologies; particularly, in this paper, oxidative technologies (ozone, cold plasma, and ionization) are reviewed. The principles underlying their mechanisms of working, generation methods, and antimicrobial activity are revised. Thanks to their ability to explain a very strong oxidative activity, the effect on microbial reduction has been resulted promising, representing a good starting point for the application in the food industry as alternative technologies for sanitization. Thus, an overview of the application of these technologies in the different food categories is done. Particularly, it has resulted that for the application of ionization technology on food, the research is still in the early stages. [ABSTRACT FROM AUTHOR]

Can low-temperature plasma technology play a role in medicine? This is a question that many investigators today are trying hard to give a positive answer to. It did not quite start out this way. Almost two decades ago, few "curious" electrical engineers and physicists with the help of few "brave" biologists! microbiologists asked themselves more basic questions: What happens to biological cells if they were exposed to low-temperature plasma? Will they die? Will they survive? If they survive, will they come out the same or somehow "injured"? If injured, will they be able to repair the damage and recover? What kind of damage? Which plasma agent causes the damage? etc. As will be shown in this paper, some of these fundamental questions have been partially or fully answered, but until today, a complete picture has yet to emerge. This is good and not so good. It is good because if we already knew all the answers, we would not be looking forward to a more exciting research. It is not so good because after all these years, we are still quite a ways from an implementable medical application. In this review paper, the present state of knowledge regarding the effects of cold plasma on bacteria cells (prokaryotes) and on eukaryotic cells (such as mammalian cells) will be presented. As medical applications where low-temperature plasma is showing signs of success, blood coagulation and wound healing will be described. [ABSTRACT FROM AUTHOR]

The aim of this paper was to assess the effectiveness, safety, stability, and mechanism of tooth whitening using a direct current cold atmospheric pressure air plasma microjet (PMJ) with the assistance of whitening gels (blank or containing 3% H2O2). The results were compared with those obtained from teeth treated with blank gel only and with gel containing 35% H2O2 in a cold light bleaching system. Tooth whitening effectiveness right after various treatments as well as 18 months after treatment was evaluated via CIELAB colorimetry. Type K thermocouple, scanning electron microscope and energy dispersive spectroscopy were employed to study the temperature of pulp chamber, tooth surface morphology, and elemental composition of enamel surface, respectively. Teeth in the plasma groups were effectively whitened in 5 min, though no significant difference was observed between the two plasma groups. Pulp chamber temperature was shown to remain below 35 °C. Morphological and surface elemental analysis showed similar changes to tooth enamel in the plasma groups and in the cold light group. These observations suggested that PMJ with blank gel was more effective for tooth whitening with acceptable safety and good stability. Optical emission spectroscopy results revealed that reactive oxygen species, such as O, •OH, and NO, in plasma may play a dominant role in the process of plasma tooth whitening. [ABSTRACT FROM AUTHOR]

Abstract: Three examples of results achieved from cooperative works with microwave and plasma research groups in Toulouse (France) are presented in this paper. They are focused on the use of few non-thermal plasmas to make a microwave device reconfigurable. The relative permittivity of such a plasma medium can be tuned from unity to negative values. This special feature appears to be very attractive, although the electromagnetic losses are significant. The use of plasmas with planar waveguides and within metamaterials is discussed. In addition, the basic principles of a scanning antenna built with a leaky wave in a plasma layer are presented. [Copyright &y& Elsevier]

Abstract: In this paper, we describe the development, functionalization and functionality testing of a TeraHertz (THz) Bio-MicroElectroMechanical System (BioMEMS) dedicated to enzyme reaction analysis. The microdevice was fabricated by mixing clean room microfabrication with cold plasma deposition. The first is used to build the microfluidic circuits and the THz sensor, while the later serves for the polymerization of allylamine using a homemade glow discharge plasma reactor for a subsequent immobilization of enzymatic biocatalysts. Thermal stability of the deposited plasma polymer has been investigated by infrared spectroscopy. Fluorescent detection confirmed the efficiency of the immobilization and the enzyme hydrolysis into the BioMEMS microchannels. For the first time, the progression of the hydrolysis reaction over time was monitored by the THz sensor connected to a vectorial network analyzer. Preliminary results showed that sub-THz transmission measurements are able to discriminate different solid films, various aqueous media and exhibit specific transmission behavior for the enzyme hydrolysis reaction in the spectral range 0.06–0.11THz. [Copyright &y& Elsevier]

This paper discusses catalyst preparation using thermal and cold plasmas. In general, there are three main trends in preparing catalysts using plasma technologies: (1) plasma chemical synthesis of ultrafine particle catalysts; (2) plasma assisted deposition of catalytically active compounds on various carriers, especially plasma spraying for the preparation of supported catalysts; (3) plasma enhanced preparation or plasma modification of catalysts. Compared to conventional catalyst preparation, there are several advantages of using plasmas, including: (1) a highly distributed active species; (2) reduced energy requirements; (3) enhanced catalyst activation, selectivity, and lifetime; (4) shortened preparation time. These advantages are leading to many potential applications of plasma prepared catalysts. [Copyright &y& Elsevier]

This paper is an essay narrating the recent history of the introduction of the biomedical applications of nonthermal plasmas to the plasma science research community. [ABSTRACT FROM AUTHOR]

Studies on the surface modification of commercial styrene-butadiene-styrene (SBS) rubber with different carbon black (CB) nanofiller content (10–80 parts per hundred parts of rubber (phr)) performed by low-pressure oxygen plasma are presented in this paper. The adhesion properties of the rubber were determined by the peel test for adhesive-bonded joints prepared with a water-based polyurethane (PU) adhesive. The chemical structure and morphology of the SBS rubber surface before and after plasma treatment were investigated by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM), respectively. The peel tests showed that the plasma treatment significantly improved the strength of adhesive-bonded joints in the entire range of CB tested, revealing a clear maximum for approximately 50 phr of CB. It was also found that as a result of plasma treatment, functional groups that are responsible for the reactions with the PU adhesive, such as C−OH and C=O, were formed, and their concentration, similar to the peel strength, showed maximum values for approximately 50 phr CB. The occurrence of these maxima was explained using the bound rubber model. [ABSTRACT FROM AUTHOR]

This paper deals with thermal ageing of polyaniline obtained from plasma or chemical ways. FTIR analyses suggest the formation of stable carbonyl compounds in both cases. The plasma polyaniline degrades clearly faster than its chemical analog which is discussed from structural considerations. The consequences of thermal ageing on the surface properties monitored by Water Contact Angles (WCA) are also considered and explained as the overlap of an "oxidation" component that decreases WCA and a "crosslinking" component (only observed in plasma polyaniline) responsible for the WCA increase. • Degradation study of polyaniline synthesized either by plasma or conventional methods. • Changes in chemical structure (FTIR) and surface properties (Water Contact Angle). • Faster degradation of plasma polyaniline compared to its conventional analog. • Ageing associated to crosslinking and oxidation for plasma polyaniline and only to oxidation for the chemical polymer. [ABSTRACT FROM AUTHOR]

Endoscopy is an important tool that can be used to identify and treat diseases and is essential to avoid cross infection when used on different people. Cold atmospheric-pressure plasmas (CAPs) offer the prospect of a future basic technology for decontaminating and sterilizing of endoscope. In this paper, we intend to design an endoscope sterilization device based on CAPs. The various lengths of gap between electrodes and electrodes themselves are considered, and the plasma distribution and its evolution are investigated. [ABSTRACT FROM PUBLISHER]

Plasma bullets have recently been used in novel applications in biology and medicine, which spurred interesting developments in the new interdisciplinary field of “Plasma Medicine.” In this paper, using high speed ICCD camera images we show that during their lifetime, plasma bullets undergo three distinctive phases: a launching phase during which the bullet velocity increases rapidly, a propagation phase during which the bullet velocity is temporarily maintained but later steadily decreases, and an ending phase during which the bullet collapses. [ABSTRACT FROM AUTHOR]

It is now well known that low-temperature plasmas can inactivate bacteria effectively. At low doses, these plasmas can also help in the proliferation of healthy fibroblasts and detach damaged cells without causing necrosis. The combination of these characteristics leads to the possibility of using plasmas in biomedical applications such as wound healing. Although only limited understanding is available as to the mechanisms whereby plasmas interact with cells (prokaryotic or eukaryotic), it is now well established that the effects of plasmas on biological cells depend on the cell type, the cell concentration, and the medium supporting them. In this paper, we present clear visual evidence of these dependencies in the case of bacteria. Through simple imaging, we show that the size and shape of the inactivation zone depend on the type of bacteria, their initial concentrations, and the medium supporting the cells. [ABSTRACT FROM AUTHOR]