In-depth electronic behavior of pentagraphene and pentagonal-silicene sheets for DNA nucleic-base detection: implications for genetic biomarker sensing

Abstract

Silicon-based chemical sensors are optimal for detecting biological entities, because of their fast biocompatible, non-invasive nature. Going beyond the hexagons in this paper we propose pristine, and metal [Gold (Au) and Tungsten (W)] atoms doped pentagonal silicene (p-Si) and pentagraphene (PG) based single DNA nucleic base sensors. Using first-principles calculations, we present a comparative study of DNA nucleic bases namely Adenine (A), Guanine (G), Cytosine (C), and Thymine (T) adsorbed on pristine and metal-doped PG and p-Si, to determine their potential as nucleic base detectors or other chemical species. The calculated binding affinity on PG and p-Si surface by M062X/6-31G* level of theory and adsorption energies by DFT predicts that PG has higher sensitivity towards DNA nucleic bases compared to p-Si with evident changes in their work function and band structure properties. In the later part, we show that the doping of Au and W has significantly enhanced the sensitivity of PG and p-Si towards the DNA nucleic bases which is also evident in their electronic band structures and PDOS calculations. The significant changes in the electronic properties of PG and p-Si with adsorbed nucleobases make it a promising candidate for rapid sensing, sequencing, and identification of DNA nucleic base elements. This study provides new insights into the physical and chemical interactions between biomolecules and PG/p-Si, highlighting its potential as a template for nanobiological devices. Both Au and W doping enhance the adsorption properties, suggesting that PG and p-Si could be effectively used for biomolecule sensing applications.