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Reactive species (RS) are the key factors of plasma‐activated solutions (PAS) against cancer. However, the specific contribution of each RS in inducing cancer cell death remain unclear. Therefore, this study aimed to evaluate the anticancer potential and mechanism of plasma‐activated medium (PAM) and plasma‐activated phosphate buffer saline (PA‐PBS) in vitro using colorectal cancer cells HCT116. Results showed that PAM and PA‐PBS effectively inhibited the growth and proliferation of HCT116 cells, with PA‐PBS exhibiting greater potency. H2O2, intracellular reactive oxygen species, and pH (H+) were essential mediators of cell death, and ONOO− exhibited cytotoxicity only after reaching a specific concentration. Additionly, PAS induced cell death through the exogenous apoptotic pathway. [ABSTRACT FROM AUTHOR]

The degradation effects and mechanism on gemfibrozil (GEM) in aqueous solution by dielectric barrier discharge (DBD) plasma combined with the catalyst CNTs/γFe2O3 are investigated. The concentrations of plasma‐generated reactive species, including H2O2, O3, NO3−, and OH, are measured with spectrophotometric and fluorescent probes. The effects of the plasma treatment period, discharge power, initial GEM concentration, solution pH value, conductivity, and the catalytic property are studied on the degradation rate and energy efficiency. Compared with the sole plasma treatment, CNTs/γFe2O3 could maximally improve the GEM degradation rate and energy efficiency to 99.7% ± 0.2% and 76.5 ± 5.2 mg·kW−1·h−1, respectively. The solution's total organic carbon removal efficiency has been increased to 47.2% ± 2.7%. Meanwhile, the possible degradation pathways of the plasma‐treated GEM solution and overall biological toxicity of GEM degradation intermediates and residual catalyst in solution are investigated. [ABSTRACT FROM AUTHOR]

The deactivation effects and mechanism of plasma‐activated water (PAW) against Staphylococcus aureus biofilm and the inhibitory effect on the biofilm regrowth capacity for the surviving S. aureus post PAW treatment were investigated in vitro. Systematic measurements on bacterial cultivability, metabolic capacity, membrane integrity and intracellular reactive oxygen species (ROS) concentration under two different experimental categories were carried out after PAW treatment. Considerable deactivation effects were discovered on biofilm S. aureus on both prolonging the PAW inducement or treatment time. The rising concentration of intracellular ROS and the PAW‐contained RS might exert synergistic effects in deactivating the biofilm S. aureus. Moreover, the biomass, bacterial cultivability and metabolic capacity of the regrown S. aureus biofilm all significantly declined along with the increasing PAW inducement or treatment time. Therefore, except for the short‐term rapid inactivation effects on the biofilm, the PAW treatment could also exert long‐term inhibitory effects on the regeneration of S. aureus biofilm. [ABSTRACT FROM AUTHOR]

A direct current (DC) gas-liquid phase atmospheric-pressure argon (Ar) plasma is used to inactivate Staphylococcus aureus suspended in the liquid. The characteristics of the gas-liquid plasma such as gas temperature, electron excitation temperature, and electron density are investigated by optical emission spectroscopy (OES). Direct plasma treatment for 40 min results in more than 2.0-log cell reduction. The emission spectra obtained from the gas-liquid phase plasma show the presence of hydroxyl radicals and atomic oxygen which give rise to effective inactivation of microorganisms. The energetic particles generated from the plasma tend to induce chemical effects such as formation of hydroxyl and hydrogen peroxide and reduced pH. The water sample after plasma treatment retains the inactivation ability for a long time and the germicidal effects arise from residual H2O2 and acidic pH. These effects have potential applications in plasma biomedicine and water purification. [ABSTRACT FROM AUTHOR]

Back Cover: A gas‐liquid DC discharge with Ar as the carrier gas is investigated and applied to inactivation of microorganism. The OH and atomic oxygen radicals are supposed to play the effective role in the plasma inactivation process. The plasma‐treated water retains the inactivation effect on bacteria for a long time which can be attributed to the synergistic effects of the plasma‐induced chemical species. Further details can be found in the article by Jie Shen et al. on page 252. [ABSTRACT FROM AUTHOR]

The degradation effects and mechanism on gemfibrozil (GEM) in aqueous solution by dielectric barrier discharge (DBD) plasma combined with the catalyst CNTs/γFe2O3 are investigated. The concentrations of plasma‐generated reactive species, including H2O2, O3, NO3−, and OH, are measured with spectrophotometric and fluorescent probes. The effects of the plasma treatment period, discharge power, initial GEM concentration, solution pH value, conductivity, and the catalytic property are studied on the degradation rate and energy efficiency. Compared with the sole plasma treatment, CNTs/γFe2O3 could maximally improve the GEM degradation rate and energy efficiency to 99.7% ± 0.2% and 76.5 ± 5.2 mg·kW−1·h−1, respectively. The solution's total organic carbon removal efficiency has been increased to 47.2% ± 2.7%. Meanwhile, the possible degradation pathways of the plasma‐treated GEM solution and overall biological toxicity of GEM degradation intermediates and residual catalyst in solution are investigated. [ABSTRACT FROM AUTHOR]