Probing Adsorption of Dipeptides on Anatase in H₂O and D₂O: Thermodynamics and Molecular Geometry

Abstract

Considering the vast importance of peptide and protein interactions with inorganic surfaces, probing hydrogen bonding during their adsorption on metal oxide surfaces is a relevant task that could shed light on the essential features of their interplay. This work is devoted to studying the dipeptides’ adsorption on anatase nanoparticles (ANs) in light and heavy water to reveal differences arising upon the change of the major hydrogen bonding carrier. Thermodynamic study of six native dipeptides’ adsorption on ANs in both media shows a strong influence of the solvent on the Gibbs free energy and the effect of side‐chain mobile protons on the entropy of the process. The adsorption is endothermic irrespective of the medium and is entropy‐driven. Computer simulations of peptide adsorption in both media shows similarity in binding via an amino group and demonstrates structural features of protonated and deuterated peptides in obtained complexes. Calculated peptide‐ anatase nanoparticle (AN) descriptors indicate surface oxygens as points of peptide‐nanoparticle contacts.

Adsorption of Low-Molecular-Weight Carboxylic Acids to Anion Exchange Resins with Various Properties and the Mechanisms of Interaction

“…The adsorption kinetics experiments were also conducted in D 2 O by adding 0.5 mL/L AERs to individual CA solutions (0.0424 mmol/L). 24 All other operational conditions in the D 2 O experiments were the same as those conducted in H 2 O.…”