Numerical simulation of chemical reactions in phosphate-buffered saline (PBS) exposed to helium pulsed plasmas at atmospheric pressure

Liquid-phase chemical reactions in phosphate-buffered saline solutions were studied with numerical simulations when the solution surfaces were exposed to electrons and ions generated in atmospheric-pressure helium (He) pulsed plasmas. The gas-phase plasmas were simulated with the particle-in-cell/Monte Carlo collisions method. In the liquid phase, one-dimensional reaction-transport model simulations and global-model simulations were employed to examine the dynamics of chemical species (i.e. solutes) in the solution. Incident electrons were found to react with water molecules and generate hydrogen molecules through the second-order recombination of solvated electrons. Incident He ions reacted with water molecules and generated hydronium ions H + and hydroxyl (OH) radicals. The OH radicals further reacted with themselves or chlorine anions (Cl − ) to form stable hydrogen peroxide (H 2 O 2 ) and hypochlorous acid (HOCl) in the solution.