QM/MD study on the ability of phosphorene for selective detection of amino acids

Abstract

In this research, by employing density functional theory dispersion corrected (DFT-D3) calculations and molecular dynamics (MD) simulations, the ability of phosphorene nanosheet for selective complex formation with different amino acids such as alanine, asparagine, aspartic acid, cysteine, histidine, and lysine was investigated. On the basis of the obtained results from quantum mechanics calculations, more stable complexes were formed between phosphorene and amino acids in the gas phase in comparison with water. Histidine due to the considerable dispersion interactions (-19.21 kcal.mol−1) with the phosphorene surface in water forms the most stable complex, which shows the importance of the dispersion interactions as the driving force in complex formation. The non-covalent interactions analysis revealed that van der Waals (vdW) interactions between the surface and amino acids have a key role in the stability of the phosphorene-amino acid complexes and confirmed the amino acid physisorption on the phosphorene surface. Donor-acceptor (DA) interaction analysis confirmed that the origin of this sensitivity can be related to the molecular orbital interactions between these amino acids and the phosphorene surface and histidine due to strong DA interaction (40.77 kcal.mol−1) with phosphorene surface can form the most stable complex in water. On the basis of the MD simulation results, phosphorene due to stronger electrostatic and vdW interactions with histidine can detect this amino acid selectively in the presence of other amino acids. Overall, the obtained results confirm that phosphorene can be a good candidate for designing new nanomaterials for selective detection of different amino acids.