Design of Biosensors Based Transition-Metal Dichalcogenide for DNA-base Detection: A First-Principles Density Functional Theory Study

The main function purpose of nanobiosensors is to sense a biologically specific material and the kind of sensing platform and doping engineering has been an emerging topic and plays an important role in monolayer molybdenum disulfide (mMoS2). In this paper, we theoretically reveal the electronic structures of mMoS2 doped by 3d transition metals. Furthermore, adsorption of nucleic acid [Adenine (A), Cytosine (C), Guanine (G), Thymine (T) and Uracil (U)] on monolayers of modified transition-metal dichalcogenides (mTMDs) such as molybdenum disulfide (MoS2) and tungsten disulfide (WS2) as a sensing platform compared using first-principles density functional theory (DFT). We have found that all nucleobases were physisorbed on TMDs due to van der Waals (vdW) interaction and demonstrated that MoS2 is better than other TMDs and may also be used to detect nucleic acid sequence for medical science. Interestingly, the adsorption energies, band structures, electronic and magnetic properties of the transition metal (TM) atom adsorbed mMoS2 efficiently modified by absorbing different TM atoms which related to their number of d electrons. The order of binding energy of the nucleobases with MoS2 and WS2 are G > A > T > C > U using DFT D3 method.