How to produce an NO_x- instead of O_x-based chemistry with a cold atmospheric plasma jet

Abstract

A novel method is presented, which allows to generate a nitrogen oxides (NOx)‐dominated chemistry with a cold atmospheric plasma (CAP) jet which typically produces an oxygen‐based reactive species (Ox) cocktail. The reactive oxygen and nitrogen (RONS) production of the CAP jet kinpen is monitored using Fourier transform infrared (FTIR) absorption spectroscopy. While in previous approaches, the plasma chemistry of CAP jets operated with noble gases has been influenced with molecular feed gas admixtures of O2 and N2, humidified feed gas, and shielding gas, these methods are now combined in order to obtain a previously unattainable range of operating regimes: The plasma chemistry can be tuned continuously from Ox to NOx dominated, while the degree of oxidation of the produced NOx can easily be influenced.

Non-touching plasma–liquid interaction – where is aqueous nitric oxide generated?

“…In the following, possible reaction mechanisms that can lead to the generation of NO in systems are discussed. In the first paragraph below, the solvation of gaseous NO in the liquid is analysed since it is known from the literature 5,44 that the investigated plasma source produced NO in the gas phase. This process could be excluded as the predominant process for the origin of the liquid phase NO.…”

“…A previous study by Schmidt-Bleker et al has shown that the generation of NO x in the gas phase by the kINPen operated with an O 2 /N 2 feed gas admixture can be enhanced by humidifying the feed gas. 5 That study has also shown that NO can also be detected in the far field (12 mm or more in front of the nozzle 5 ) of the jet, if the feed gas is humidified and a N 2 gas curtain is applied. However, it is noted that in the near field (from the nozzle until 12 mm 1 ) (6) and 7), the detected downstream nitrogen oxides (H x NO y ) are an indicator of the presence of NO in the effluent.…”

“…Interestingly, also the biologically highly relevant nitric oxide ( NO) can be found in the gas phase and plasma treated liquids, sparking the interest of both fundamental and applied research. 5 The molecule is a comparably stable radical and has a key position in diverse biological cascades like vascular and neuronal signal transduction, cell death, or host defense. [6][7][8] The primary targets of NO are specific heme-iron receptors, the soluble or bound guanylate cyclases (GCs), promoting the production of cyclic guanosine monophosphate as the major downstream effector.…”

Investigation of Power Transmission of a Helium Plasma Jet to Different Dielectric Targets Considering Operating Modes

“…Over the throttle valve, the gas produced by the plasma source in its controlled atmosphere was aspirated into the multi-pass cell. Figure 2 depicts the overall setup that has previously been used e.g., in [26]. The measurement captured a wavenumber range of 700 to 4000 cm −1 , which allowed the detection of several nitrogen compounds such as nitric oxide (NO) and nitrous oxide (N 2 O) in addition to the expected most abundant species O 3 and NO 2 in the far-field.…”

Treating cancer with cold physical plasma: On the way to evidence‐based medicine

“…Third, clinical plasma medicine without support, monitoring, and supervision by scientific plasma research jeopardizes the benefit of patients and deceives their trust in medical professionalism. The role of clinicians on the way to EBM in plasma medicine is to ask the right questions to stimulate basic research …”