Exploring the nature of interaction and stability between DNA/RNA base pairs and defective & defect-dopant graphene sheets. A possible insights on DNA/RNA sequencing

A quantum chemical investigation is performed to understand the adsorption behaviour of DNA/RNA base pairs onto the defective (Di-Vacancy (DV) and Stone-Wales (SW)), boron (B) and silicon (Si) defect-dopant graphene (B-DV, Si-DV, B-SW, and Si-SW) sheets using density functional theory (DFT). The stability of DNA/RNA base pairs on the Si-SW sheet is found to be -80.59 kcal/mol (G-C), -70.21 kcal/mol (A-T), and -69.78 kcal/mol (A-U). The quantum theory of atoms in molecule (QTAIM) analysis concluded that the interaction of DNA/RNA base pair on Si-SW sheet has partially electrostatic and partially covalent (Si center dot center dot center dot N) characters. The natural bond orbital analysis (NBO), electron density difference map (EDDM), and natural population analysis (NPA) are revealed that the charge has been transferred from DNA/RNA base pair to defective and defective-dopant graphene sheet. From the time-dependent density functional theory (TD-DFT), a strong redshift is observed at 482 nm for GC-Si-SW, 494 nm for AT-Si-SW, and 497 nm for AU-Si-SW. Hence, the substantial variations in the HOMO-LUMO gap (Delta E-HL) and UV spectra of Si-SW sheet after the adsorption of DNA/RNA base pair can be beneficially exploited to design a new bio-sensor or DNA/RNA sequencing devices. (C) 2020 Elsevier B.V. All rights reserved.