scholarly journals Influence of Microwave Frequency and Gas Humidity on the In-Vitro Blood Coagulation in Cold Atmospheric Pressure Plasma

Processes ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1837
Author(s):  
Jie Yu ◽  
Li Wu ◽  
Kama Huang

In this article, the effects of microwave frequency (2450 MHz and 5800 MHz) and gas humidity (1%, 2%, 3%, 4%, 6% and 8%) on in vitro blood coagulation with cold atmospheric pressure plasma (CAPP) were investigated. The generation of reactive oxygen species (ROS, OH, O) was measured by optical emission spectra. The exposure temperature on blood droplets under treatment was below 55 °C in all cases, to avoid the thermal effect of plasma on the blood clotting. Investigations showed that, with the increase of frequency, the doses of ROS increased, the blood sample presented a more serious collapse and its surface became drier. The humidity of ionized gas can also accelerate the generation of ROS and the process of blood clotting. Our results propose a method to accelerate in vitro blood coagulation in CAPP by adjusting microwave frequency and gas humidity, and suggest a clinical benefit for plasma treatment as a coagulation device in surgery.

Infection ◽  
2021 ◽  
Author(s):  
Sebastian Gnat ◽  
Dominik Łagowski ◽  
Mariusz Dyląg ◽  
Jessica Zielinski ◽  
Marek Studziński ◽  
...  

Abstract Purpose Anthropophilic dermatophytes as etiological factors of onychomycoses are more common than zoophilic fungi. In the case of the latter, reverse zoonoses are possible, which poses a threat to the persistence of dermatophytes in the environment. Nevertheless, without treatment, both types of tinea unguium may lead to complete nail plate destruction and secondary mixed infections with fungi and bacteria. One of the zoophilic dermatophytes that cause onychomycosis is Trichophyton verrucosum, whose prevalence has been increasing in recent years. Such infections are usually treated with allylamines and/or azoles, but such a conventional treatment of infections caused by T. verrucosum often fails or is discontinued by patients. Methods Herein, we reveal the results of our in vitro studies related to direct application of cold atmospheric pressure plasma (CAPP) on Trichophyton verrucosum growth, germination and adherence to nail as a new alternative treatment method of such types of dermatomycoses. Results Our in vitro studies showed that, while exposure to CAPP for 10 min delays germination of conidia and clearly impairs the fitness of the fungal structures, 15 min is enough to kill all fungal elements exposed to plasma. Moreover, the SEM images revealed that T. verrucosum cultures exposed to CAPP for 10 and 15 min were not able to invade the nail fragments. Conclusion The results revealed that single exposure to CAPP was able to inhibit T. verrucosum growth and infection capacity. Hence, cold atmospheric pressure plasma should be considered as a promising alternative treatment of onychomycoses.


2019 ◽  
Vol 14 (1) ◽  
pp. 37-45 ◽  
Author(s):  
Khaled Lotfy ◽  
Sayed Mohammed Khalil ◽  
Hany Abd El-Raheem

AbstractA helium cold atmospheric pressure plasma jet (HCAPPJ) driven by a commercial neon power supply was designed and utilized for inactivation bacteria. The generated reactive spices by HCAPPJ were investigated by optical emission spectroscopy. The reactive species of OH, OI, OI, N21+, N21+ and He were identified in the UV–Vis wavelength region. The reactive species was not detected between 200 nm and 300 nm, as the flow rate of helium gas increased that led to the plasma temperature reducing to a value near to the room temperature. In this work, we studied the impact of HCAPPJ on Gram-positive and Gram-negative bacteria. The survival amounts of the two types of bacteria were decreased vastly when the rate flow rate was equal to 10 L/min.


2021 ◽  
Vol 11 (15) ◽  
pp. 6870
Author(s):  
Atif H. Asghar ◽  
Ahmed Rida Galaly

Dry argon (Ar) discharge and wet oxygen/argon (O2/Ar) admixture discharge for alternating current atmospheric pressure plasma jets (APPJs) were studied for Ar discharges with flow rates ranging from 0.2 to 4 slm and for O2/Ar discharges with different O2 ratios and flow rates ranging from 2.5 to 15 mslm. The voltage–current waveform signals of APPJ discharge, gas flow rate, photo-imaging of the plasma jet length and width, discharge plasma power, axial temperature distribution, optical emission spectra, and irradiance were investigated. Different behavior for varying oxygen content in the admixture discharge was observed. The temperature recognizably decreased, axially, far away from the nozzle of the jet as the flow rate of dry argon decreased. Similar behavior was observed for wet argon but with a lower temperature than for dry argon. The optical emission spectra and the dose rate of irradiance of a plasma jet discharge were investigated as a function of plasma jet length, for dry and wet Ar discharges, to determine the data compatible with the International Commission on Non-Ionizing Radiation Protection (ICNIRP) data for irradiance exposure limits of the skin, which are suitable for the disinfection of microbes on the skin without harmful effects, equivalent to 30 μJ/mm2.


2019 ◽  
Vol 1 (1) ◽  
pp. 46-52
Author(s):  
Vasu D ◽  
Raji A ◽  
Pandiyaraj K.N ◽  
Padmanabhan P.V.A ◽  
Kandhavelu V

In this study we investigate the degradation of telmisartan (Telma-H) in simulated aqueous solution using non-thermal atmospheric pressure plasma jet (APPJ). Aqueous solution containing Telma-H was treated with APPJ as a function of applied potential and reaction time. The degradation of Telma-H was investigated by means of UV-Visible spectroscopy. Optical emission spectra (OES) of the plasma jet was used to identify the reactive species that contributed to degrade Telma H compounds. The variation of pH and conductivity of the plasma treated Telma H aqueous solution was also measured.


2012 ◽  
Vol 260-261 ◽  
pp. 114-119 ◽  
Author(s):  
Shao Xia Jia ◽  
Ling Li Zhao ◽  
Jing Hua Yang ◽  
Chen Zhang ◽  
Shou Gou Wang

A novel radio frequency single-dielectric-barrier-discharge atmospheric pressure plasma generator was designed and utilized to strip AZ9912 photo-resist (PR). Argon (Ar) and oxygen (O2) were employed as the working gases under atmospheric pressure in ambient air. The PR stripping rate was measured as functions of time, input power, and the flow rates of the oxygen/argon. Optical Emission Spectroscopy (OES) was used to measure the optical emission spectra of the plasma to study the mechanism of PR stripping process. It is presumable that C-H bands were broken by high energy electron in the plasma and OH was generated in the process with the participation of O atom. Optical Microscope, Atomic Force Microscope (AFM) and Scanning Electron Microscope (SEM) were used to measure the surface of the silicon substrate after the stripping. It is proved that this kind of novel device could strip the AZ9912 PR effectively as high as 850nm/min, without residues and ion bombardment damage on the wafer substrate.


2019 ◽  
Vol 34 (2) ◽  
pp. 329-336 ◽  
Author(s):  
Ralf Smeets ◽  
Anders Henningsen ◽  
Roman Heuberger ◽  
Oliver Hanisch ◽  
Frank Schwarz ◽  
...  

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