Adsorption of Native Amino Acids on Nanocrystalline TiO₂: Physical Chemistry, QSPR, and Theoretical Modeling

Abstract

The affinity of biomolecules, such as peptides and proteins, with inorganic surfaces, is a fundamental topic in biotechnology and bionanotechnology. Amino acids are often used as “model” bits of peptides or proteins for studying their properties in different environments and/or developing functional surfaces. Despite great demand for knowledge about amino acid interactions with metal oxide surfaces, studies on the issue represent a fragmentary picture. In this paper, we describe amino acid adsorption on nanocrystalline anatase systematically at uniform conditions. Analysis of the Gibbs free adsorption energy indicated how the aliphatic, aromatic, polar, and charged side chain groups affect the binding affinity of the amino acids. Thermodynamic features of the l-amino acid adsorption receive thorough interpretation with calculated molecular descriptors. Theoretical modeling shows that amino acids complex with TiO2 nanoparticles as zwitterions via ammonium group.

Unusual Synthesis of Triosmium Carbene Clusters by Tandem Activation of Chlorohydrocarbons and Heterocyclic Amines

“…Then, for each of the obtained conformers, a conformational search was performed for the turns relative to all other bonds in order to find a conformer that meets the minimum potential energy for a given angle φ (torsion angle C2−C1−Os2−C22). The energy was calculated with the MERA force field with a continual counting intermolecular interactions of cluster complex in the solution [16–18] …”

Thermodynamic Impact of Mineral Surfaces on Amino Acid Polymerization: Aspartate Dimerization on Two-Line Ferrihydrite, Anatase, and γ-Alumina

“…However, even Asp adsorption remains controversial in spectroscopic and computational investigations (Table A3). The proposed functional groups crucial for Asp binding on TiO 2 , for example, includes the amino group (NH 3 + or NH 2 ) [44,45], side chain methylene group [46], and either or both of the α-COOand β-COOgroups [47][48][49][50][51]. These disagreements probably indicate the difficulty in determining the Asp interfacial structure rather than reflect the difference in the examined TiO 2 surface environments [52].…”

Recent advances in theoretical investigation of titanium dioxide nanomaterials. A review

“…The DNA base binding to the TiO 2 surface was rather weak, so that desorption back into the bulk solvent was observed [86]. Single amino acids or short peptides have been the first molecules to be computationally studied [13,[80][81][88][89]. Ab initio periodic calculations and classical MD simulations were performed to investigate the adsorption mode, conformational characteristics, and inter-adsorbate interactions of alanine and several dipeptides, such as alanine-glutamic acid and alanine-lysine onto the TiO 2 (110) rutile surface [30,90].…”