Influence of Gas Temperature in Atmospheric Non-Equilibrium Plasma on Bactericidal Effect.

In this study, the relationship between plasma gas temperature and the bactericidal effects on five of bacteria (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis and Bacillus cereus (spore)) in liquid was investigated using a temperature-controllable plasma source. We determined that the bactericidal ability improved as the plasma gas temperature increased. Specifically, the bactericidal ability on E.

Endoscopic Hemostasis in Porcine Gastrointestinal Tract Using CO Low-Temperature Plasma Jet.

Background: Recently, atmospheric low-temperature plasma (LTP) has attracted attention as a novel medical tool that might be useful for achieving hemostasis. However, conventional plasma sources are too big for use with endoscopes, and the efficacy of LTP for achieving hemostasis in cases of gastrointestinal bleeding is difficult to investigate. In this study, to solve the problem, we developed a 3D-printed LTP jet that has a diameter of 2.

Development of a Dual Plasma Desorption/Ionization System for the Noncontact and Highly Sensitive Analysis of Surface Adhesive Compounds.

We developed a dual plasma desorption/ionization system using two plasmas for the semi-invasive analysis of compounds on heat-sensitive substrates such as skin. The first plasma was used for the desorption of the surface compounds, whereas the second was used for the ionization of the desorbed compounds. Using the two plasmas, each process can be optimized individually.

Investigation of blood coagulation effect of nonthermal multigas plasma jet in vitro and in vivo.

Background: Nonthermal atmospheric pressure plasma (NTAPP) has recently received attention as a novel tool in medicine. It is thought that plasma components yield plasma effects such as sterilization, blood coagulation, and wound healing. These effects are produced without thermal damage.

Development of a High-Density Microplasma Emission Source for a Micro Total Analysis System.

To achieve a highly sensitive and onsite analysis of a small amount samples, a microplasma-based micro total analysis systems (μ-TAS) device was developed. A dielectric barrier discharge (DBD) that can generate a stable plasma at atmospheric pressure was generated in a microchip and used as the plasma source. The use of DBD suppresses the temperature rise of the electrodes and enables operation for long times because of a reduction of the electrode damage due to suppression of the current via dielectric interposing between the electrodes.

Direct protein introduction into plant cells using a multi-gas plasma jet.

Protein introduction into cells is more difficult in plants than in mammalian cells, although it was reported that protein introduction was successful in shoot apical meristem and leaves only together with a cell-penetrating peptide. In this study, we tried to introduce superfolder green fluorescent protein (sGFP)-fused to adenylate cyclase as a reporter protein without a cell-penetrating peptide into the cells of tobacco leaves by treatment with atmospheric non-thermal plasmas. For this purpose, CO2 or N2 plasma was generated using a multi-gas plasma jet.

Irradiation effects of low temperature multi gas plasma jet on oral bacteria.

The purpose of this study is to evaluate the sterilization effects of a newly developed low temperature multi gas plasma jet on oral pathogenic microorganisms (Streptococcus mutans [S. mutans], Lactobacillus fermentum [L. fermentum], Aggregatibacter actinomycetemcomitans [A.

Imaging of the Staphylococcus aureus Inactivation Process Induced by a Multigas Plasma Jet.

To identify mechanisms underlying the bacterial inactivation process by atmospheric nonthermal plasma using a unique plasma jet that can generate various gas plasmas, Staphylococcus aureus were irradiated with carbon dioxide plasma, which produces a large amount of singlet oxygens, and nitrogen plasma, which produces a large amount of OH radicals. And damaged areas of plasma-treated bacteria were observed by field emission scanning electron microscopy, transmission electron microscopy, and atomic force microscopy. As a result, bacteria were damaged by both gas plasmas, but the site of damage differed according to gas species.

Development of Desolvation System for Single-cell Analysis Using Droplet Injection Inductively Coupled Plasma Atomic Emission Spectroscopy.

With a view to enhance the sensitivity of analytical instruments used in the measurement of trace elements contained in a single cell, we have now equipped the previously reported micro-droplet injection system (M-DIS) with a desolvation system. This modified M-DIS was coupled to inductively coupled plasma atomic emission spectroscopy (ICP-AES) and evaluated for its ability to measure trace elements. A flow rate of 100 mL/min for the additional gas and a measurement point -7.

Microbial Inactivation in the Liquid Phase Induced by Multigas Plasma Jet.

Various gas atmospheric nonthermal plasmas were generated using a multigas plasma jet to treat microbial suspensions. Results indicated that carbon dioxide and nitrogen plasma had high sterilization effects. Carbon dioxide plasma, which generated the greatest amount of singlet oxygen than other gas plasmas, killed general bacteria and some fungi.

Development of a gas-cylinder-free plasma desorption/ionization system for on-site detection of chemical warfare agents.

A gas-cylinder-free plasma desorption/ionization system was developed to realize a mobile on-site analytical device for detection of chemical warfare agents (CWAs). In this system, the plasma source was directly connected to the inlet of a mass spectrometer. The plasma can be generated with ambient air, which is drawn into the discharge region by negative pressure in the mass spectrometer.

Fundamental properties of a touchable high-power pulsed microplasma jet and its application as a desorption/ionization source for ambient mass spectrometry.

Plasma-based ambient desorption/ionization mass spectrometry (ADI-MS) has attracted considerable attention in many fields because of its capacity for direct sample analyses. In this study, a high-power pulsed microplasma jet (HPPMJ) was developed and investigated as a new plasma desorption/ionization source. In an HPPMJ, a microhollow cathode discharge is generated in a small hole (500 µm in diameter) using a pulsed high-power supply.

Decomposition of tetrodotoxin using multi-gas plasma jet.

In this study, non-thermal multi-gas plasma treatments were performed for Tetrodotoxin (TTX) solution, and TTX decomposition was analyzed by liquid chromatography coupled with electrospray time-of-flight mass spectrometry. The TTX mass spectrum signal was reduced by plasma irradiations to different levels by using various gas species. Nitrogen plasma exhibited the optimal capability for TTX decomposition, followed by oxygen, argon, and carbon dioxide plasmas.

A new air-cooled argon/helium-compatible inductively coupled plasma torch.

A new inductively coupled plasma (ICP) torch with an air-cooling system has been designed and developed for both argon and helium plasma. The same torch and impedance-matching network could be used to generate stable Ar- and He-ICP. The torch consists of three concentric quartz tubes.

Settlement of planulae of the Moon jellyfish Aurelia aurita onto hydrophilic polycarbonate plates modified by atmospheric plasma treatment.

It has been reported that planula larvae of some jellyfish prefer artificial substrates for settlement. This research focused on the relationship between the settlement of planulae and the wettability of artificial substrate surfaces. We used atmospheric plasmas to change the wettability of the surfaces of polycarbonate (PC) plates because plasma treatment has no chemical side effects.

Development of injection gas heating system for introducing large droplets to inductively coupled plasma.

We developed an injection gas heating system for introducing large droplets, because we want to effectively to measure elements in a single cell. This system was applied to ICP-atomic emission spectrometry (ICP-AES), to evaluate it performance. To evaluate the effect of the emission intensity, the emission intensity of Ca(II) increased to a maximum of tenfold at 147°C and the peak was shifted upstream of the plasma.

Development of the atmospheric plasma soft-ablation method (APSA) for elemental analysis of materials on heat-sensitive substrates.

To achieve a highly sensitive and prompt elemental analysis of materials on heat-sensitive substrates, like living tissues, the atmospheric plasma soft-ablation method (APSA) was developed. The damage-free plasma, which has room temperature and no risk of electrical shock, was used as a sampling medium for materials, and the sampled materials were introduced to inductively coupled plasma mass spectrometer (ICP-MS). By using APSA, a mass signal of molybdenum, using a thin molybdenum-grease layer, was successfully obtained without damaging the subjacent glass substrate.

Wide-bore capillary hydrodynamic chromatography with ICP-MS detection for evaluation of lanthanide uptake by molecular aggregates.

Wide-bore capillary hydrodynamic chromatography (W-HDC) resolves analytes on the basis of a difference in the extent of radial diffusion simply by their passage through an empty capillary. The combination of this method with ICP-MS proves efficient for the evaluation of the interaction of metal ions with molecular aggregates. Lecithin vesicles are suitable molecular aggregates for the uptake of the lanthanide ions in the presence of the first row transition metal ions, suggesting that the present method is applicable to the screening of the molecular aggregate system suitable for selective extraction of a particular targeted small molecule.