Key Engineering Materials Vol. 990

Abstract: The evaluation of chitosan and resveratrol interactions has been conducted using density functional theory (DFT) to model a slow-release system of the active ingredient resveratrol from the chitosan matrix. The geometry optimization method for modeling was selected using the DFT/B3LYP method with various basis sets. Molecularly imprinted chitosan (MIC) complex models with resveratrol were created in two different configurations. All models were optimized using selected computational methods. The optimized complex models were used to calculate interaction energies and analyze the non-covalent interactions between the MIC cavity and resveratrol. The MIC-resveratrol complex models formed relatively stable supramolecular complexes with a relatively low interaction energy of - 199 kJ/mol for omplex model namely B1 and formed four hydrogen bonds with bond lengths around 1.79-1.91 Å.

Abstract: The interaction of dopamine and Si-, Sn-, and BN-doped fullerenes was studied by using the density functional theory (DFT). Adsorption energies of dopamine–C60, dopamine–C59Si, dopamine–C58Sn, and dopamine–C58BN were -0.03 eV, -1.46 eV, -0.06 eV, and -0.05 eV, respectively. All systems had negative adsorption energies, indicating that dopamine can be adsorbed on fullerene. Furthermore, dopamine–C59Si had the smallest value and was chemisorbed shown by a created covalent bond between Si of fullerene and N of dopamine. Therefore, C59Si has a plausible potential as a drug carrier for dopamine molecules.

Abstract: The effect of biaxial and uniaxial strains on the electronic structure of anatase is studied using Density Functional Theory (DFT) calculation with ultrasoft pseudopotential and a generalized gradient approximation (GGA) Perdew-Burke Ernzerhof (PBE) exchange-correlation. The lattice constant is optimized using the Birch-Murnaghan equation of states (BM-EOS) to get an optimized geometric structure of anatase TiO₂. We apply biaxial and uniaxial strains to this optimized structure up to 16% and find that the applied strains change the band gap energy compared to a pure anatase with a different band gap energy up to 1.61 eV for biaxial strain and 0.35 eV for uniaxial strain. The biaxial strains increase gap energies except at +16% tensile strain, decreasing the gap energy to 0.04 eV. Uniaxial strains tend to increase as the strains increase except at-12 and-16%; their gap energy differences are 0.08 and 0.20 eV, respectively, smaller than that of the zero strain. The results also show that the applied 16% tensile strain significantly lengthens the atomic bonds; thus, we conclude that the maximum strain applied to anatase TiO₂ is 16%.

Abstract: The explosive sensitivity of the supramolecular interaction between cations (Mⁿ⁺ = Li⁺, Na⁺, K⁺, Be²⁺, Ca²⁺ and Mg²⁺) with enol tautomers (c0 and c1) of 3-nitro-1,2,4-triazole-5-one (NTO) complexes has been investigated using Density Functional Theory (DFT). The effect of water as the solvent was included via the CPCM approach. At the gas phase, the presence of the metal cations, especially Be²⁺, significantly increased the bond dissociation energy (BDE) of C-NO₂ of the enol tautomers. However, in the presence of the solvent, the BDE was lower than in the gas phase, even in the supramolecular complex of Be²⁺ - c0 and Be²⁺ - c1.

Abstract: Molecular docking and molecular dynamics on substituted indole derivatives-Leucine Trasporter had been performed. Indole derivatives with methoxy and fluorine group are chosen and specific amino acid residue Arg30 and Asp404 are π-alkyl and π-cation interactions. The suggested molecule containing methoxy groups has an RMSD value of 1.95 Å, a binding energy of-4.00 kcal mol^-1, and an inhibition constant of 1.17 μM. The hypothesized fluorine-containing compound's RMSD value, binding energy, and inhibition constant were each 1.88 Å; -5.97 kcal mol^-1; and 41.88 μM, respectively. The substituted indole derivative with the methoxy group was stable, according to the findings of a 200-ns molecular dynamics simulation, while the substituted indole derivative with the fluorine group was less stable. Based on the examination of RMSD, RMSF, RoG, the quantity of hydrogen, and the level of contact stability of the ligands with the particular amino acid residues for the antidepressant drug, the dynamical interaction of ligands against LeuT was determined.