The direct and indirect bactericidal effects of dielectric barrier discharge (DBD) cold atmospheric-pressure microplasma in an air and plasma jet generated in an argon-oxygen gas mixture was investigated on Staphylococcus aureus and Cutibacterium acnes. An AC power supply was used to generate plasma at relatively low discharge voltages (0.9–2.4 kV) and frequency (27–30 kHz). Cultured bacteria were cultivated at a serial dilution of 10⁻⁵, then exposed to direct microplasma treatment and indirect treatment through plasma-activated water (PAW). The obtained results revealed that these methods of bacterial inactivation showed a 2 and 1 log reduction in the number of survived CFU/mL with direct treatment being the most effective means of treatment at just 3 min using air. UV–Vis spectroscopy confirmed that an increase in treatment time at 1.2% O₂, 98.8% Ar caused a decrease in O₂ concentration in the water as well as a decrease in absorbance of the peaks at 210 nm, which are attributed NO₂⁻ and NO₃⁻ concentration in the water, termed denitratification and denitritification in the treated water, respectively.

A study of the transdermal delivery of Cyclosporine A by atmospheric plasma irradiation was realized on the epidermal layer of the Hairless Yucatan micropig. Drug flux and the amount of drug penetrated through the skin were determined by a Franz cell diffusion experiment. After treatment of the skin by atmospheric plasma jet or microplasma dielectric barrier discharge, an increase in the permeability of the skin was observed. The authors did not observe drug penetration for samples that were not treated with plasma. There was no significant difference between treatments of skin by plasma jet or microplasma dielectric barrier discharge. Drug flux increased to its maximal value up to 3 h after the drug application, and then it decreased. This phenomenon could indicate a temporal effect of plasma on skin. A pharmacokinetic two-compartment model was developed to estimate the possibility of using plasma drug delivery of Cyclosporine A in medical praxis. Our model showed that it is possible to use this technique if a suitable treatment area and concentration of applied drug are chosen.

This work studies the ability of laser-induced breakdown spectroscopy (LIBS) to improve the detection of light elements such as silicon (Si), boron (B), carbon (C), and sulfur (S). In this study, the plasma decay over time was simulated using the LIBS application provided by NIST, obtaining spectra in the spectral range ranging from the vacuum ultraviolet (VUV) to the near infrared (NIR) region. Since the electron density ( n _e ) and plasma temperature ( T _e ) decrease during the decaying process, the intensities of emission lines from neutral, singly ionized, and doubly ionized species were calculated. The results allowed us to determine the range of suitable n _e and T _e for experimental measurements, and to construct a Saha–Boltzmann (SB) plot using neutral, singly ionized, and doubly ionized species. Samples containing Si, B, C, and S were measured at delays of 100–1000 ns after the laser shot at low pressure (13 mbar) in a helium atmosphere. From the measured data, suitable lines were chosen in the VUV range to calculate the T _e of plasma for each sample at different delays. The results demonstrate that due to the inclusion of multiple species across VUV–UV–NIR, an appreciable improvement in the accuracy of T _e was obtained, which is an essential factor for calibration-free LIBS (CF-LIBS).