Production of nitric monoxide using pulsed discharges for a medical application

Abstract

Nitric monoxide (NO) is widely used in medical treatment of acute respiratory distress syndrome (ARDS). The production of NO is of interest to the medical community. In the present work, NO is generated by pulsed discharges between two rod electrodes in a mixture of nitrogen and oxygen. An arc discharge having a temperature of about 10 000K was produced, which was sufficient to generate NO. Some of the important parameters affecting the production of NO have been investigated. These include the percentage of O 2 (6-94%) in the mixture of N 2 and O 2 , the energy of the discharge (0.5-12 J/pulse), the pulse repetition rate (0.5-4.5 pps) and the flow rate (1.35-5.4 l/min) of the gas mixture. NO 2 produced in the discharge was successfully changed to NO using a heated molybdenum tube. NO 2 must be extracted from the gas before clinical inhalation. The concentration of ozone was completely eliminated by bubbling the gas mixture through water. A maximum of NO and a minimum of NO 2 concentrations were generated when the proportion of O 2 in the gas mixture was in the range of 20-27%. The concentrations of NO and NO 2 increased with increasing pulse repetition rate and with decreasing flow rate of the mixture. In all cases, NO 2 was effectively removed using a heated molybdenum tube.Index Terms-Acute respiratory distress syndrome, medical application, nitric monoxide, pulsed arc discharge.. Manuscript

Low-Current Plasmatron as a Source of Nitrogen Oxide Molecules

“…It turned out that the average discharge current and the average discharge-burning voltage practically do not depend on the gas flow G(air). Correspondingly, the curves in It is seen that the content of NO in the output gas is higher than that of NO 2 which is typically for the generation of nitrogen oxides in the gas discharges [43]- [45]. Prima facie, decreasing [NO] with the gas flow G(air) seems to be evident since, in the exit chamber, we dilute the nitrogen oxides with the air.…”

“…From the aforementioned reasoning, it is of interest to compare the conditions of NO generation in our experiments with the conditions in the papers [43] and [44], where the high-current spark discharge with a duration of about several microseconds had been used. A typical energy in the spark was of 5 J at a pulse-repetition rate of 2 Hz.…”

“…The flows of nitrogen oxides and ozone generated in the plasma jets are applied for disinfection of wounds and skin wound healing [45]. Correspondingly, different types of gas discharge in air and oxygen/nitrogen flow have been proposed for production of these particles, for example, a high-current spark discharge in a regime pulse-repetition rate [43], [44], a gliding arc discharge [46], and a microwave discharge powered by a frequency of 2.4 GHz [45].…”

“…Among the active particles, the molecules of nitrogen oxides and ozone have a significant place, particularly for the biomedical applications. Nitric monoxide is widely used in inhalation therapy because it has a relaxing effect on the blood vessels [43], [44]. The flows of nitrogen oxides and ozone generated in the plasma jets are applied for disinfection of wounds and skin wound healing [45].…”

Nitric Oxide Generator Based on Pulsed Arc Discharge

“…Therefore, an on-site production of NO with low cost would be highly desirable for patients and medical doctors. We have reported the production of NO based on a pulsed arc discharge [5][6][7]. In the present work, NO generator based on a pulsed arc discharge was developed and it was evaluated as the medical device.…”