1H, 31P NMR, Raman and FTIR spectroscopies for investigating phosphoric acid dissociation to understand phosphate ion kinetics in body fluids

Abstract

The study investigates the formation and transportation of ionic charge carriers in phosphoric acid-water system. This investigation encompasses an analysis of 1H and 31P NMR chemical shifts, self-diffusion coefficients, spin-lattice relaxation rates, spin-spin relaxation rates, activation energies, dissociation constants, electrical conductivity, and Raman shifts, along with FTIR spectra across various water concentrations. Significantly, the maxima observed in these curves at around 0.8 water molar fraction predominantly from the unique molecular arrangement between phosphoric acid and water molecules, influenced by a hydrogen bonding network. These findings yield valuable insights into phosphate ion kinetics within body fluids, covering essential aspects like hydrogen bonding networks, ionization processes, and the energy kinetics of phosphoric dissociation. A customized semiempirical model is applied to calculate dissociated species (water, phosphoric acid, and hydronium ion) at different water contents within a wide range of water mole fraction. Furthermore, this investigation extends to the dissociation of phosphoric acid in DMEM cell culture media, offering a more precise model for phosphate ionic kinetics within body fluids, especially at nominal phosphate concentrations of approximately 1:700μL.