Biomaterial−Biomolecule Interaction: DFT-D Study of Glycine Adsorption on Cr₂O₃

Abstract

The adsorption of glycine, the smallest amino acid and building block of proteins, on a Cr 2 O 3 surface, taken as a model of stainless steel surfaces, was studied by means of GGA + U (on site Coulomb repulsion). The role of coverage on the adsorption mode and the self-assembly properties were explored. The dispersion contribution to the adsorption energies was also calculated. Glycine adsorbs at low and high coverage in the anionic form. The adsorption is driven by the formation of iono-covalent bonds with the Cr surface atoms. The most stable configurations correspond to maximization of the bonds (Cr-O and Cr-N), where the O or N atoms replace O atoms from the missing anionic plane above the terminal Cr plane. To maximize the bonds formation and minimize lateral repulsion, glycine lies parallel to the surface at low coverage and has a bent orientation at high coverage. The inclusion of dispersion forces strengthens this trend. At mean coverage under the ML, clusterization of high density domains may coexist with domains of lower coverage at the surface. At saturation, a glycinate monolayer with a 1:1 Gly:Cr ratio is formed.

Adsorption of Molecules onto (101̅4) Dolomite Surface: An Application of Computational Studies for Microcalorimetry

“…Hence, the adsorption energy will be −13.90 kcal/mol, consistent with previous studies of water adsorption on the TiO 2 surface. 26 On the other hand, to explore the application of other methods that can describe the low dispersion interactions of the adsorption processes, we applied the semiempirical Grimme dispersion correction for a single-point energy PBE/GGA DFT calculation (DFT-D) 39 on the structures optimized previously above, following the procedure of previous studies about adsorption on other metal oxides, 46 and the adsorption energy was slightly higher than without this correction (18.45 kcal/ mol). Besides, we explored another approach to include the dispersion correction by fully optimizing adsorption complex and reactant with PBE/GGA + Grimme correction; however, this yielded too high adsorption energy (27.9 kcal/mol).…”

Understanding small biomolecule‐biomaterial interactions: A review of fundamental theoretical and experimental approaches for biomolecule interactions with inorganic surfaces

“…Briefly, Grimme's D2 (respectively D3) approach considers the two‐body term of the dispersive interaction at the sixth‐ (respectively sixth‐ and eight‐) order for any atom pair. More details about the methods can be found in Ref 75. and references cited there‐in.…”

“…The interactions of amino‐acids with dry surfaces were studied. On Al 2 O 3 ,79 Cr 2 O 3 ,75 and ZnO,82 the glycinate anion is the most stable form, with the formation of a M‐OCO adduct. The interaction of amino acids with hydroxyapatite is of electrostatic nature, strong bonds being formed between the acid or basic functionalities and the Ca 2+ cation 85, 88–90…”

The growth of Nin clusters and their interaction with cubic, monoclinic, and tetragonal ZrO2 surfaces–a theoretical and experimental study

“…Adsorption energies and activation barriers of reactants and intermediates on catalyst surfaces can be calculated accurately through the electronic structure theory. 2,[27][28][29] In this way, the chemistry can be understood, and promising directions can be predicted. [23][24][25][26] Vital information in many reactions involving metal-support interaction, such as the surface chemistry of oxide-supported metal clusters, atom and electron transfer, as well as detailed structure of the interface, can be obtained.…”