D-Glucose Oxidation by Cold Atmospheric Plasma-Induced Reactive Species

The glucose oxidation cascade is fascinating; although oxidation products have high economic value, they can manipulate the biological activity through posttranslational modification such as glycosylation of proteins, lipids, and nucleic acids. The concept of this work is based on the ability of reactive species induced by cold atmospheric plasma (CAP) in aqueous liquids and the corresponding gas-liquid interface to oxidize biomolecules under ambient conditions. Here, we report the oxidation of glucose by an argon-based dielectric barrier discharge plasma jet (kINPen) with a special emphasis on examining the reaction pathway to pinpoint the most prominent reactive species engaged in the observed oxidative transformation. Employing D-glucose and D-glucose -13C6 solutions and high-resolution mass spectrometry and ESItandem MS/MS spectrometry techniques, the occurrence of glucose oxidation products, for example, aldonic acids and aldaric acids, glucono-and glucaro-actones, as well as less abundant sugar acids including ribonic acid, arabinuronic acid, oxoadipic acid, 3-deoxyribose, glutaconic acid, and glucic acid were surveyed. The findings provide deep insights into CAP chemistry, reflecting a switch of reactive species generation with the feed gas modulation (Ar or Ar/O-2 with N-2 curtain gas). Depending on the gas phase composition, a combination of oxygen-derived short-lived hydroxyl (& BULL;OH)/atomic oxygen [O(3P)] radicals was found responsible for the glucose oxidation cascade. The results further illustrate that the presence of carbohydrates in cell culture media, gel formulations (agar), or other liquid targets (juices) modulate the availability of CAP-generated species in vitro. In addition, a glycocalyx is attached to many mammalian proteins, which is essential for the respective physiologic role. It might be questioned if its oxidation a role in CAP

Automated summary

The study investigates the oxidation of glucose by cold atmospheric plasma and identifies the reactive species responsible for the observed oxidative transformation. The results demonstrate the ability of oxygen-derived radicals to initiate the glucose oxidation cascade. Additionally, the presence of carbohydrates in cell culture media and other liquid targets is found to modulate the availability of plasma-generated species.