Peroxynitrous Acid Generated In Situ from Acidified H2O2 and NaNO2. A Suitable Novel Antimicrobial Agent?

Abstract

Peroxynitrite (ONOO−) and peroxynitrous acid (ONOOH) are known as short acting reactive species with nitrating and oxidative properties, which are associated with their antimicrobial effect. However, to the best of our knowledge, ONOOH/ONOO- are not yet used as antimicrobial actives in practical applications. The aim is to elucidate if ONOOH generated in situ from acidified hydrogen peroxide (H2O2) and sodium nitrite (NaNO2) may serve as an antimicrobial active in disinfectants. Therefore, the dose-response relationship and mutagenicity are investigated. Antimicrobial efficacy was investigated by suspension tests and mutagenicity by the Ames test. Tests were conducted with E. coli. For investigating the dose-response relationship, pH values and concentrations of H2O2 and NaNO2 were varied. The antimicrobial efficacy is correlated to the dose of ONOOH, which is determined by numerical computations. The relationship can be described by the efficacy parameter W, corresponding to the amount of educts consumed during exposure time. Sufficient inactivation was observed whenever W ≥ 1 mM, yielding a criterion for inactivation of E. coli by acidified H2O2 and NaNO2. No mutagenicity of ONOOH was noticed. While further investigations are necessary, results indicate that safe and effective usage of ONOOH generated from acidified H2O2 and NaNO2 as a novel active in disinfectants is conceivable.

Impact of Nonthermal Plasma on Lipid Oxidation from the Perspective of Plasma Treatment Parameters and Plasma Species: Identification of Key Reactive Species

“…Peroxynitric acid (O 2 NOOH) was synthesized by the reaction between NaNO 2 and an excess amount of H 2 O 2 (30%) in HNO 3 (65%), and the concentration of O 2 NOOH in the resulting product solution (ca. 3.5 mL) was determined to be 1.12 M by iodometric titration. , Ten microliters of the synthesized O 2 NOOH solution was then added into 1.0 g of stripped linseed oil methylesters in a 10 mL tube, and the mixture was vortexed for 60 s. Since peroxynitrous acid (ONOOH) is short-living in an aqueous solution, 2.1 M sodium nitrite and hydrogen peroxide were prepared separately in phosphate buffer (pH = 3.2) . Ten microliters of the prepared sodium nitrite and hydrogen peroxide solution were added simultaneously into 1.0 g of stripped linseed oil methylesters and vortexed for 60 s. To check the effect of nitric acid, 10 μL of HNO 3 (65%) was added into 1.0 g of stripped linseed oil methylesters and vortexed for 60 s. All the treatments were performed independently, after which 5 mL of distilled water was added to stop the reaction, and the lipid fraction was extracted three times with 5 mL of n -hexane.…”

“…23,24 Ten microliters of the synthesized O 2 NOOH solution was then added into 1.0 g of stripped linseed oil methylesters in a 10 mL tube, and the mixture was vortexed for 60 s. Since peroxynitrous acid (ONOOH) is short-living in an aqueous solution, 2.1 M sodium nitrite and hydrogen peroxide were prepared separately in phosphate buffer (pH = 3.2). 25 Ten microliters of the prepared sodium nitrite and hydrogen peroxide solution were added simultaneously into 1.0 g of stripped linseed oil methylesters and vortexed for 60 s. To check the effect of nitric acid, 10 μL of HNO 3 (65%) was added into 1.0 g of stripped linseed oil methylesters and vortexed for 60 s. All the treatments were performed independently, after which 5 mL of distilled water was added to stop the reaction, and the lipid fraction was extracted three times with 5 mL of n-hexane. The lipid extract was dried over anhydrous sodium sulfate, rotaevaporated at 20 °C under vacuum, kept under nitrogen for 30 min, and analyzed immediately thereafter.…”

Medical gas plasma technology: Roadmap on cancer treatment and immunotherapy

“…Both agents are stable enough also to reach cancer cells at longer distances. There is also evidence of ONOO - -dominated chemistries, which, however, are thought to be more important in antimicrobial gas plasma effects [ [133] , [134] , [135] ]. As mentioned above, it is also rather short-lived and appears in only low concentrations in the nanomolar to micromolar range under cell culture conditions following gas plasma exposure [ 128 , 136 ].…”

Gliding arc discharge used for water activation: the production mechanism of aqueous NO and its role in sterilization

“…However, the OH radicals in the plasma effluent gas can rarely enter the water due to its short lifetime, so it could be presumed that H 2 O 2 mainly originates from the dissolution of H 2 O 2 from the gas phase (R6). The main reactions are as follows [31][32][33]: Peroxynitrite and NO are two typical short-lived species in PAW that have been widely reported to be associated with sterilization [20,34], and the content of these two species in PAW is analyzed in this paper. As shown in figure 5, negligible peroxynitrite is detected, and its concentration does not vary significantly with activating conditions.…”