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Effectively removing pollutants from wastewater remains a significant challenge to achieving a sustainable future. Dyes are a class of pollutants that exhibit chemical stability, are not biodegradable, and have the potential to convert into dangerous substances. Layered double hydroxides (LDHs) have emerged as a promising adsorbent for addressing this problem due to their ion-exchange properties and high surface area. Recent studies indicate that the effectiveness of the LDHs can be further improved by delamination into nano sheets.In this manuscript we explore the use of argon dielectric barrier discharge (DBD) plasma, a type of non-thermal plasma, as an innovative, greener and milder method to delaminate CuMgAl-LDH turning it into nanosheets. Congo Red (CR) dye was selected as the model pollutant in this study. The resulting plasma treated CuMgAl-LDH (P-CuMgAl-LDH) exhibits a better CR dye adsorption rate. The photodegradation of CR at a concentration of 500 mg L−1 was achieved using 1.0 mg mL−1 of P-CuMgAl-LDH and irradiating with a 370 nm LED. It was found that P-CuMgAl-LDH has significantly higher performance, showing a full discoloration of CR within 1 h and up to 80 % of mineralisation within 1.5 h of irradiation compared to only 16.1 % for CuMgAl-LDH. The photodegradation mechanism studies reveals highly efficient formation of superoxide radical anions (O2-•) that further confirm the presence of oxygen vacancies on the P-CuMgAl-LDH. Thus, we conclude that Argon DBD plasma is a valuable tool to efficiently delaminate CuMgAl-LDH under mild conditions and improve its adsorption and photocatalytic properties without the addition of other chemicals.

Abstract Recently, non-thermal plasma (NTP) technologies have found widespread application across diverse fields, including plant growth, medical science, and biological and environmental research. Rice (Oryza sativa L.) is exceptionally sensitive to temperature changes. Notably, low-temperature stress primarily affects the germination and reproductive stages of rice, often leading to reduced crop yield. This study aimed to identify optimal conditions for enhancing rice seed germination and seedling growth under low temperatures using NTP technology. Our research indicated that NTP treatment at 15.0 kV for 30 s optimally promotes rice seed germination and growth under low-temperature stress. Furthermore, NTP treatment increases the activity and expression of antioxidant enzymes, such as superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), under low-temperature conditions. Moreover, it downregulates the expression of β-ketoacyl-[acyl carrier protein] synthase I (KASI) and cis-epoxy carotenoid dioxygenase 3 (NCED3) and upregulates the expression of alternative oxidase (AOX1B), BREVIS RADIX-like homologous gene (BRXL2), WRKY transcription factor 29 (WRKY29), and EREBP transcription factor 2 (EREBP2) in roots after tandem 7 days low-temperature (16 ℃) and 7 days room-temperature (28 ℃) treatments. Transcriptomic analysis revealed the involvement of various key genes in phosphotransferase activity, phosphate-containing compound metabolic processes, and defense responses. These analyses provide comprehensive information on gene expression at the transcriptional level, offering new insights for a deeper understanding of candidate genes required for root growth in rice.

Plasma from electric discharges can be used in the abatement of volatile organic compounds (VOCs). The application of gas-phase pulsed corona discharge (PCD) in air–water mixtures provides favorable conditions for the oxidation of VOCs at unsurpassed energy efficiency. This research investigates the impact of water sprinkling on PCD performance in the oxidation of m-xylene as a model compound. Experimental research into the plasma treatment of continuous air flow was undertaken using the PCD reactor in dry and water-sprinkled modes. Water sprinkling more than doubled the m-xylene oxidation rate, which can be attributed to abundant OH-radicals produced at the plasma–water interface. Water sprinkling substantially reduced the formation of nitrous oxide, which is considered to be a secondary pollutant in the outlet air. Ozone is considered a by-product helping the subsequent photocatalytic oxidation of potential residues and photocatalyst maintenance. The use of water-sprinkled PCD is a promising approach to energy-efficient abatement of VOCs.

Tetracyclines comprise a large group of broad-spectrum antibiotics used in human and veterinary medicine. Its mechanism of action, via oral ingestion, is to inhibit bacterial protein synthesis, but a large amount (70%) is eliminated without being metabolized, which presents a risk for the arising of antibiotic-resistant species. In this study, the degradation of Tetracycline TC by non-thermal plasma NTP and the antimicrobial sensitivity of the treated solution are investigated. The degradation was followed by chromatographic analysis while the efficiency of NTP in inhibiting the action of TC on bacteria was evaluated by antimicrobial sensitivity test by disk diffusion method. The results showed a high rate of TC degradation, over 90%, in 10 min of NTP treatment for a 60 mL (107 mg L-1) sample and very slow increase up to 94% in 30 min. The antimicrobial sensitivity test of TC after degradation by NTP showed no antibiotic activity. Therefore, our findings are encouraging, since the removal efficiency is below the minimum threshold require, to prevent with high probability, outgrowth of antibiotic-resistant bacteria. In addition, the results confirm that the NTP treated solution is safe to the environment.

Non-thermal plasma driven ammonia synthesis has great potential for future industrial applications due to its low theoretical energy requirements. To achieve technological advancement and environmental sustainability, it is crucial to boost the energy yield in plasma-assisted ammonia synthesis. Therefore, optimizing energy transfer and utilization are key strategies for enhancing energy efficiency. In this study, dielectric barrier discharge driven by a nanosecond pulsed power supply is used to enhance plasma-assisted ammonia synthesis by controlling the energy transfer through the addition of noble gases. It was found that the addition of noble gases changed the plasma characteristics, significantly improved the uniformity of the discharge, and achieved a high energy yield for ammonia synthesis. The effects of additive amounts of argon (Ar) and helium (He), as well as the pulse parameters including the pulse voltage, pulse repetition frequency, pulse width, and pulse rise time on the energy yield of ammonia synthesis are discussed. The inclusion of noble gases expanded the pathway for gas-phase reactions, with the active components of critical reactions examined through optical emission spectra. This analysis revealed an increased presence of both N2+ and N2* particles in the reaction’s rate-limiting step, attributed to the addition of noble gases. Finally, a zero-dimensional (0D) plasma chemical kinetic model was established to investigate the influence of Ar addition on the reaction mechanism of ammonia synthesis.

Graphene is a 2D nanomaterial that has received increasing attention due to its remarkable properties, such as high electric and thermal conductivity and good mechanical properties. The insertion of heteroatoms onto graphene enables the control of various properties of the material, such as dispersion, catalysis and band gap. Among the heteroatoms studied, sulfur is attractive due to its versatility, being part of functional groups that enhance dispersion and enable further modification. Various methods of sulfur functionalization were studied, and non-thermal plasma distinguishes itself due to its energy efficiency, ease of operation, and low heating of the treated material. However, existing non-thermal plasma methods are limited due to the expense of the equipment, energy consumption due to vacuum conditions and limited treated mass.In this work, we present a brand new simple, low-cost method for sulfur functionalization of graphene by argon non-thermal plasma discharged over an aqueous medium containing potassium thiocyanate, operating at ambient pressure and temperature. The modified graphene obtained was analyzed by Raman, XPS, FTIR, zeta potential and thiol quantification. The results showed an increase in graphene dispersion in water caused by the insertion of sulfonic acid and thiol functional groups onto the graphene structure, while maintaining the pristine qualities of the starting material.

Cercospora leaf spot disease is a serious problem for lettuce cultivation worldwide. Cercospora lactucae-sativa, the causative agent of leaf spot disease on lettuce, was treated with non-thermal atmospheric pressure gliding arc (GA), tesla coil (TC) and dielectric barrier discharge (DBD) plasmas for the in vitro fungal inactivation of both mycelial growth and conidial germination. The fungus was exposed to the three plasmas individually for 5, 10, 15 and 20 min. The results showed that DBD plasma inactivated fungal growth during all exposure periods, and the highest inhibitory effect was caused by exposure to DBD plasma for 20 min, at 93.33% inhibition. The germination of fungal conidia was completely inactivated after exposure to all three non-thermal plasmas for 5 min, as observed 4 and 24 h after incubation. The pathogenesis of C. lactucae-sativa on lettuce after plasma treatments for 5 min was examined by spraying an inoculation of the treated conidia on lettuce. The results showed that all three plasmas reduced the disease incidence and severity compared to the non-treated control. Therefore, the non-thermal atmospheric pressure GA, TC and DBD plasmas have antifungal potential for the inactivation of C. lactucae-sativa, making them an interesting novel technology for plant disease control.

Perfluorosurfactants (PFS) are global environmental pollutants and are considered as a new anthropogenic type of carcinogenic contaminant that remains untreated by conventional wastewater treatment plants. These organic surfactants are typically refractory, non-biodegradable, and pose great threats to environmental safety and human health. The gradual increase in PFS product consumption by various industries resulted in their abundant occurrence in the ecosystem. Non-thermal plasma-based advanced oxidation processes with powerful oxidation ability appeared to be applicable for the degradation of refractory organic pollutants and enhancing biodegradability. In this work, the decomposition of Perfluorooctanesulfonic acid (PFOS) in water by the application of nano-second pulse corona discharge under oxygen was examined. Working corona discharge under oxygen, argon, and helium has no effects on the decomposition rate. The energy yields at 50% conversion (G50) of about 1 mg L−1 initial PFOS concentration was estimated as 22 mg/kWh under argon or oxygen and 27 mg/kWh under helium. The energy yield G50 for initial concentrations of 7.5 and 18.5 µg L−1 in helium and oxygen was estimated as 0.20 and 0.33 mg/kWh, respectively. A considerable difference in the generation of short perfluoroalkyl acids by-products and fluoride ions was observed when corona discharge was conducted under oxygen and much more of these by-products are formed. A synergistic effect was observed in the presence of other surface-active compounds. Degradation efficiency was enhanced by 10% after the addition of surface-active sulfobetaine into the medium following the same experimental procedure.

The growing need for increasingly miniaturized devices has placed high importance and demands on nanofabrication technologies with high-quality, low temperatures, and low-cost techniques. In the past few years, the development and recent advances in atomic layer deposition (ALD) processes boosted interest in their use in advanced electronic and nano/microelectromechanical systems (NEMS/MEMS) device manufacturing. In this context, non-thermal plasma (NTP) technology has been highlighted because it allowed the ALD technique to expand its process window and the fabrication of several nanomaterials at reduced temperatures, allowing thermosensitive substrates to be covered with good formability and uniformity. In this review article, we comprehensively describe how the NTP changed the ALD universe and expanded it in device fabrication for different applications. We also present an overview of the efforts and developed strategies to gather the NTP and ALD technologies with the consecutive formation of plasma-assisted ALD (PA-ALD) technique, which has been successfully applied in nanofabrication and surface modification. The advantages and limitations currently faced by this technique are presented and discussed. We conclude this review by showing the atomic layer etching (ALE) technique, another development of NTP and ALD junction that has gained more and more attention by allowing significant advancements in plasma-assisted nanofabrication.

Demand to improve food quality attributes without the use of chemicals has risen exponentially in the past few years. Non-thermal plasma (NTP) (also called ‘cold plasma’) is becoming increasingly popular for this purpose due to its unique low-temperature and non-chemical nature. In the present research, the concept of in situ dielectric barrier discharge (DBD) plasma treatment inside a rotational reactor for the direct treatment of wheat flour was experimentally analyzed. The primary research goal was to determine the effects of short-period NTP treatment of DBD type on flour and dough properties. For this purpose, the influence of different operating parameters was tested, i.e., treatment time, the amount of flour placed in the reactor and the environmental (air) temperature. Changes in the structural attributes of the most commonly used flours (type 550 and 1050) and their respective doughs were studied using a set of analytical techniques. Rheological analysis demonstrated the ability of NTP to significantly intensify the visco-elastic properties of dough produced from wheat flour type 550 that was treated for less than 180 s. This indicated that plasma treatment enhanced intermolecular disulphide bonds in gluten proteins, which resulted in stronger protein–starch network formations. However, longer treatment times did not result in a significant increase in the visco-elastic properties of wheat dough. The obtained results showed a 6–7% increase in flour hydration due to NTP treatment, which also makes a contribution to hydrogen bonding due to changes in the bonded and free water phase. Experimental findings further confirmed the dependence of NTP treatment efficiency on environmental air temperature.

In this work, the surface dielectric barrier discharge (SDBD) plasma treatment was used to sterilize the palm date fruits. N2SPS, N2FNS, and hydroxyl radical have emerged in the emission spectrum of the plasma from SDBD. The effects of SDBD plasma on A. niger that was extracted from palm date varieties were investigated. After 15 days of incubation, the reduction of A. niger at a 3 min exposure time was 4 log. The total phenolic content of the Ajwa variety after SDBD plasma treatment has been documented as the highest value among the other varieties; it was 1.65-fold of the untreated one. The treated Ajwa variety using SDBD plasma has recorded the highest increase in antioxidant activity; it was increased to 67.69% compared to the control one. After SDBD plasma treatment, the HMF was not detected in the Maghol variety. According to the PCA model, the first two PCs demonstrated strong positive correlations with most of the examined variables and demonstrated a strong positive correlation between these variables when assessed in both untreated and treated with SDBD plasma of palm date types in this stud.

Upcycling is an attractive approach for valorization of waste plastics to valuable chemicals. Here we report the first case study of non-thermal plasma-assisted hydrogenolysis of high-density polyethylene (HDPE) to C1-C3 hydrocarbons. Light alkanes, predominately CH4, C2H6 and C3H8 with >95% selectivity, were obtained under ambient condition as result of favorable thermodynamics and fast reaction kinetics. The findings demonstrated that hydrogenolysis that typically demands above 300 °C with thermal catalysis can occur at room temperature in assistance of non-thermal plasma. This proof-of-concept study showcases a novel strategy for upcycling of plastics to valuable hydrocarbons under ambient condition.

The pulsed dielectric barrier discharge (DBD) combined with the palladium supported on alumina beads, was investigated for propene (C3H6) removal from air. The effects of thermal-catalysis, plasma-catalysis (in-plasma catalysis and post-plasma catalysis), and plasma-alone on the propene removal were compared. Results are presented in the terms of C3H6 removal efficiency, energy consumption, and by-products production. Temperature dependence studies (20–250°C) show that in all conditions of input plasma energy density explored (23–148 J L-1), the plasma-catalysis systems exhibit better propene conversion efficiencies than the thermal catalysis at low temperature (60% at 20°C). Plasma-alone treatment has a similar effectiveness compared to plasma-catalysis at room temperature, but it leads to the formation of high by-products concentrations. It appears that in the plasma-catalyst system, C3H6 removal was the most efficient, whatever was the configuration used, and it was helpful to minimize by-products formation.

Denture stomatitis is a disease involving C. albicans, which can affect elderly and immuno-compromised people. To avoid any recurrence of this pathology, it is necessary to treat patients regularly and disinfect dentures. However, the denture cleansers’ efficacy is not optimal and often leads to adverse color effects on the denture base resins. The aim of this study was to investigate the efficacy of a low-pressure non-thermal O2 plasma (NTP) treatment on C. albicans seeded on ProBase®Hot resin (Ivoclar Vivadent). The viability reduction of C. albicans was assessed by colony forming units (CFU) analysis and by scanning electron microscopy (SEM). The effect of repeated treatments on the resin color was evaluated by spectrophotometry. The resin samples were placed in a sealed bag in which O2 plasma was generated in low-pressure conditions. The results showed that a 120-min O2 NTP treatment led to a 6-log reduction of C. albicans viability (p < 0.05) and to yeasts’ major alterations observed by SEM. Furthermore, significant slight color changes of the resin (∆E00 = 1.33) were noted only after six plasma treatments (p < 0.05). However, the denture aesthetic was preserved, as the color changes were not perceptible and remained below the acceptability threshold (∆E00 < 4).

This work is a contribution to the development and implementation of non-thermal plasma technology for decontamination in the perspective of nosocomial and chronic wound innovative therapies. Multi jets devices based on Plasma Gun® technology in static and scanning operation modes and bacterial lawns inoculated with resistant and non-resistant bacterial strains were designed and used. A pilot toxicity study exploring plasma treatment of wound bearing patients, performed with a low voltage plasma applicator, is documented as a first step for the translation of in vitro experiments to clinical care. Bacterial inactivation was demonstrated for Staphylococcus aureus, Pseudomonas aeruginosa and drug resistant S. aureus, P. aeruginosa and Escherichia Coli strains collected from patient wounds at Orleans (France) hospital. A few square centimeter large contaminated samples were inactivated following a single plasma exposure as short as one minute. Samples inoculated with a single but also a mix of three resistant pathogens were successfully inactivated not only right after their contamination but for mature lawns as well. Similar bactericidal action was demonstrated for antibiotic-resistant and non-resistant P. aeruginosa. The time exposure dependent increase of the inhibition spots, following multi jets exposure, is discussed as either the accumulation of reactive species or the likely combinatory action of both the reactive species and transient electric field delivery on inoculated samples.

In this paper, an experimental setup was established to study the influence of potassium chloride (KCL) solution as the ground electrode on the nitrogen oxides (NOx) removal efficiency in non-thermal plasma (NTP) generated by dielectric barrier discharging (DBD) reactor. The experimental results show that the KCL solution as the ground electrode has better stability and higher discharge intensity and it is a promising approach to improve NOx removal efficiency. The specific NOx removal efficiency is related to the power frequency, the concentration and temperature of the KCL solution. As the power frequency increases, the NOx removal efficiency first increases and then decreases, and a maximum value is reached at the power frequency of 8 kHz. The NO removal effect is improved as the concentration of the KCL solution increases, especially when the concentration is lower than 0.1 mol/L. Under the same KCL solution concentration and input energy density, the NOx removal efficiency is increased with the solution temperature. In particular, when the power discharge frequency is 8 kHz, the KCL solution concentration is 0.1 mol/L and the solution temperature is 60 °C, the NOx and NO removal efficiency reach 85.82% and 100%, respectively.

Transient spark (TS), a DC-driven self-pulsing discharge generating a highly reactive atmospheric pressure air plasma, was employed as a rich source of NOx. In dry air, TS generates high concentrations of NO and NO2, increasing approximately linearly with increasing input energy density (Ed), reaching 1200 and 180 ppm of NO and NO2, at Ed = 400 J/L, respectively. In humid air, the concentration of NO2 decreased down to 120 ppm in favor of HNO2 that reached approximately 100 ppm at Ed = 400 J/L. The advantage of TS is its capability of simultaneous generation of the plasma and the formation of microdroplets by the electrospray (ES) of water directly inside the discharge zone. The TS discharge can thus efficiently generate plasma-activated water (PAW) with high concentration of H2O2−(aq), NO2−(aq) and NO3−(aq), because water microdroplets significantly increase the plasma-liquid interaction interface. This enables a fast transfer of species such as NO, NO2, HNO2 from the gas into water. In this study, we compare TS with water ES in a one stage system and TS operated in dry or humid air followed by water ES in a two-stage system, and show that gaseous HNO2, rather than NO or NO2, plays a major role in the formation of NO2−(aq) in PAW that reached the concentration up to 2.7 mM.

Booming biodiesel production worldwide demands valorization of its byproduct of glycerol. Acrolein, an important intermediate chemical, can be produced by gas-phase glycerol dehydration catalyzed by solid acids. Because catalysts that lead to high acrolein selectivity usually deactivate rapidly due to the formation of coke that blocks the active sites on their surface, one major challenge of this method is how to extend the service life of the catalyst. Silica-supported silicotungstic acid (HSiW-Si) is a good example of such a catalyst that shows good activity in glycerol dehydration to acrolein initially, but deactivates quickly. In this study, HSiW-Si was selected to probe the potential of using non-thermal plasma with oxygen-containing gas as the discharge gas (NTP-O2) to solve the catalyst deactivation problem. NTP-O2 was found to be effective in coke removal and catalyst regeneration at low temperatures without damaging the Keggin structure of the HSiW-Si catalyst.

Plasma medicine is the utilization of gas ionization that might be beneficial for the treatment of burn wounds, a healthcare problem with a significant mortality rate. Due to a lack of information on the impact of plasma flux in immune cells and a high prevalence of bacterial infection in burn wounds, non-thermal argon-based plasma flux was tested on macrophages (RAW246.7) and in mouse models of burn wounds with or without Staphylococcus aureus infection. Accordingly, plasma flux enhanced reactive oxygen species (ROS), using dihydroethidium assay, and decreased abundance of NF-κB-p65 (Western blot analysis) in non-stimulating macrophages. In parallel, plasma flux upregulated IL-10 gene expression (an anti-inflammatory cytokine) in lipopolysaccharide (LPS)-induced inflammatory macrophages, while downregulating the pro-inflammatory cytokines (IL-1β and IL-6). Additionally, plasma flux improved the migratory function of fibroblasts (L929) (fibroblast scratch assay) but not fibroblast proliferation. Moreover, once daily plasma flux administration for 7 days promoted the healing process in burn wounds with or without infection (wound area and wound rank score). Additionally, plasma flux reduced tissue cytokines (TNF-α and IL-6) in burn wounds with infection and promoted collagen in burn wounds without infection. In conclusion, plasma flux induced anti-inflammatory macrophages and promoted the burn-wound healing process partly through the decrease in macrophage NF-κB. Hence, plasma flux treatment should be tested in patients with burn wounds.

Various reactive oxygen and nitrogen species are accompanied by electrons, ultra-violet (UV) radiation, ions, photons, and electric fields in non-thermal atmospheric pressure plasma. Plasma technology is already used in diverse fields, such as biomedicine, dentistry, agriculture, ozone generation, chemical synthesis, surface treatment, and coating. Non-thermal atmospheric pressure plasma is also considered a promising technology in environmental pollution control. The degradation of organic and inorganic pollutants will be massively advanced by plasma-generated reactive species. Various investigations on the use of non-thermal atmospheric pressure plasma technology for organic wastewater purification have already been performed, and advancements are continuing to be made in this area. This work provides a critical review of the ongoing improvements related to the use of non-thermal plasma in wastewater control and outlines the operational principle, standards, parameters, and boundaries with a special focus on the degradation of organic compounds in wastewater treatment.

The era of evolution in power electronic systems has led to a widespread displacement of power supplies operating at mains frequencies. Switched-mode power inverters offer possibilities incomparably higher than mains transformers. These trends have also entered into plasma technologies, including GlidArc plasma processing. The article presents the use of an inverter power supply for a miniaturized GlidArc. It is a demonstration of using a push–pull topology in an unusual application. A special part is devoted to parasitic phenomena in the inverter and the implementation of switching overvoltages as a way of improving the ignition parameters of the power supply. The results of the tests with a plasma reactor in air conditions as a process gas are also presented.

In this study, the catalytic effect of TiO2-ZnO/GAC coupled with non-thermal plasma was investigated on the byproducts distribution of decomposition of chlorinated VOCs in gas streams. The effect of specific input energy, and initial gas composition was examined in a corona discharge reactor energized by a high frequency pulsed power supply. Detected by-products for catalytic NTP at 750 J L-1 included CO, CO2, Cl2, trichloroacetaldehyde, as well as trichlorobenzaldehyde with chloroform feeding, while they were dominated by CO, CO2, and lower abundance of trichlorobenzaldehyde and Cl2 with chlorobenzene introduction. Some of the by-products such as O3, NO, NO2, and COCl2 disappeared totally over TiO2-ZnO/GAC. Furthermore, the amount of heavy products such as trichlorobenzaldehyde decreased significantly in favor of small molecules such as CO, CO2, and Cl2 with the hybrid process. The selectivity towards COx soared up to 77% over the catalyst at 750 J L-1 and 100 ppm of chlorobenzene.

Non-thermal plasma (NTP), defined as a partially ionized gas, is an emerging technology with several biomedical applications, including tissue regeneration. In particular, NTP treatment has been shown to activate endogenous biological processes to promote cell regrowth, differentiation, and proliferation in multiple cell types. However, the effects of this therapy on nervous system regeneration have not yet been established. Accordingly, the current study explored the effects of a nanosecond-pulsed dielectric barrier discharge plasma on neural regeneration. Following mechanical trauma in vitro, plasma was applied either directly to (1) astrocytes alone, (2) neurons alone, or (3) neurons or astrocytes in a non-contact co-culture. Remarkably, we identified NTP treatment intensities that accelerated both neurite regeneration and astrocyte regrowth. In astrocyte cultures alone, an exposure of 20−90 mJ accelerated astrocyte re-growth up to three days post-injury, while neurons required lower treatment intensities (≤20 mJ) to achieve sub-lethal outgrowth. Following injury to neurons in non-contact co-culture with astrocytes, 20 mJ exposure of plasma to only neurons or astrocytes resulted in increased neurite regeneration at three days post-treatment compared to the untreated, but no enhancement was observed when both cell types were treated. At day seven, although regeneration further increased, NTP did not elicit a significant increase from the control. However, plasma exposure at higher intensities was found to be injurious, underscoring the need to optimize exposure levels. These results suggest that growth-promoting physiological responses may be elicited via properly calibrated NTP treatment to neurons and/or astrocytes. This could be exploited to accelerate neurite re-growth and modulate neuron-astrocyte interactions, thereby hastening nervous system regeneration.

In this work, cyclopropylamine (CPA) monomer was plasma-polymerized on poly (ε-caprolactone) nanofiber meshes using various deposition durations to obtain amine-rich surfaces in an effort to improve the cellular response of the meshes. Scanning electron microscopy and X-ray photoelectron spectroscopy (XPS) were used to investigate the surface morphology and surface chemical composition of the PCL samples, respectively. The measured coating thickness was found to linearly increase with deposition duration at a deposition rate of 0.465 nm/s. XPS analysis revealed that plasma exposure time had a considerable effect on the surface N/C and O/C ratio as well as on amino grafting efficiency and amino selectivity. In addition, cell studies showed that cell adhesion and proliferation significantly improved for all coated samples.

The formation of bacterial biofilm on implanted devices or damaged tissues leads to biomaterial-associated infections often resulting in life-threatening diseases and implant failure. It is a challenging process to eradicate biofilms as they are resistant to antimicrobial treatments. Conventional techniques, such as high heat and chemicals exposure, may not be suitable for biofilm removal in nosocomial settings. These techniques create surface degradation on the treated materials and lead to environmental pollution due to the use of toxic chemicals. A novel technique known as non-thermal plasma has a great potential to decontaminate or sterilize those nosocomial biofilms. This article aims to provide readers with an extensive review of non-thermal plasma and biofilms to facilitate further investigations. A brief introduction summarizes the problem caused by biofilms in hospital settings with current techniques used for biofilm inactivation followed by the literature review strategy. The remainder of the review discusses plasma and its generation, the role played by plasma reactive species, various factors affecting the antimicrobial efficacy of non-thermal plasma and summarizes many studies published in the field.

Application of plasma medicine has been actively explored during last several years. Treating every type of cancer remains a difficult task for medical personnel due to the wide variety of cancer cell selectivity. Research in advanced plasma physics has led to the development of different types of non-thermal plasma devices, such as plasma jets, and dielectric barrier discharges. Non-thermal plasma generates many charged particles and reactive species when brought into contact with biological samples. The main constituents include reactive nitrogen species, reactive oxygen species, and plasma ultra-violets. These species can be applied to synthesize biologically important nanomaterials or can be used with nanomaterials for various kinds of biomedical applications to improve human health. This review reports recent updates on plasma-based synthesis of biologically important nanomaterials and synergy of plasma with nanomaterials for various kind of biological applications.

Biofilm formation on implanted medical devices is the reason for most of the nosocomial infections in clinical settings. Biofilms are more resistant to antimicrobials than their planktonic cells mainly because of the presence of the matrix of extracellular polymeric substances (EPSs), which acts as a physical barrier that limits the transport of antimicrobials inside the biofilm. A combinatorial antimicrobial approach of a non-thermal plasma and chlorhexidine (CHX) digluconate can be used to sterilize those surfaces contaminated with biofilm. However, the reason behind achieving this combinatorial decontamination is not known. Thus, in this study, we developed a mathematical model to explain the reason behind sterilization with the combinatorial treatment approach. It was found that the application of plasma prior to treatment with CHX is disrupting the biofilm and making it very porous. This is allowing CHX to penetrate deeper inside the porous biofilm, which is then effective at sterilizing the biofilm.

Since NOx family, one of the most important causes of air pollution, is the primary source of acid rains, ozone layer depletion, and breathing disorders, mitigation of these pollutants is now a global concern. In the off-gases of internal combustion engines running with oxygen excess, non-thermal plasmas (NTPs) have an oxidative potential, which results in an effective conversion of NO to NO2. This paper aims at studying the methods of mitigating and eliminating NOx in an atmospheric and non-thermal condition by means of plasma reactors. It examines some key parameters such as temperature, space velocity, voltage, and propane/NOx mole ratio. The results showed that, the space velocity in the 11500-2300 h-1 domain did not show any significant results on the NOx conversion. Our findings also revealed that the optimal conditions for conversion of NO into N2, O2, and NO2 are temperature (180 ◦C), voltage (10 kV), and equal mole ratio of propane in NOx. In this condition, the optimal conversion efficiency of 78% and the standard deviation of 12% were obtained. The optimal temperature, voltage, and the mole ratio of propane in NOx conversion to N2 and O2. (efficiency=53% ) are 180◦C, 5 kV, and 0.3 respectively. Plasma reactor acts as primery treatment in the direct mitigation of NOx into neutral and non-poisonous molecules of O2 and N2.