Microscopic Mechanistic Study of the Penetration Distributions for Plasma Reactive Oxygen and Nitrogen Species Based on Sialic Acid Targeting on the Cell Membrane Surface

Biomedical applications of cold atmospheric plasmas (CAPs) is an important and highly regarded research direction, in which reactive oxygen and nitrogen species (RONS) play crucial roles. During the uses of CAPs with biological tissues, surface components such as sialic acid on the membrane undergo oxidation and modification by the RONS. This article explores the potential of using sialic acid as a cancer treatment target with molecular dynamics simulations and investigates the penetration distributions of peroxynitrite (ONOOH)and its decomposition products NO
2
and OH radicals at the membrane-water interface. Research results indicate that an increase in sialic acid content on the surface of tumor cells decreases the stability of the membrane system, making it easier for RONS to penetrate into the cells and cause oxidative damage to important cellular structures. Sialic acid can thus be considered a potential target for plasma therapy in cancer treatment. Studies have found that plasma jet can promote the homolytic decomposition of ONOOH, with the resulting hydroxyl radicals exhibiting stronger interactions with sialic acid molecules compared to ONOOH. This contributes to a better understanding of the oxidative modification reactions of sialic acid molecules in the membrane environment. Additionally, appropriate electric field stimulation enhances the depth of RONS penetration, thereby more effectively treating pathological conditions of biological tissues while minimizing necrotic cell death in healthy cells to a certain extent. The differential hydrophilic and hydrophobic properties of ONOOH and its decomposition products offer insights into the mechanism of long-distance RONS penetration. The findings of this study provide valuable references for precise targeting of cancer cells in plasma therapy, facilitating further clinical translation of plasma biomedical applications.