Design and screening of DNA/RNA sequencing materials based on non-metallic substituted molybdenum sulfide: A density functional theory study

Abstract

Molybdenum disulfide (MoS₂) monolayers are promising materials for the electrochemical sensing of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) nucleobases. However, pristine MoS₂ has low sensitivity and selectivity for nucleobase detection. In this study, we used density functional theory (DFT) calculations to investigate how doping MoS₂ with boron (B), carbon (C), nitrogen (N), and oxygen (O) affects its interactions with nucleobases (adenine, cytosine, guanine, thymine, and uracil respectively). We calculated the adsorption energies, response values, and recovery times of nucleobases on doped MoS₂ and compared them with those of pristine MoS2. We found that B-, C-, and O-doped MoS₂ enhanced the identification and differentiation between nucleobases, but B- and C-doped MoS2 had long recovery times due to the formation of strong chemical bonds between MoS₂ and the nucleobases. In contrast, O-doped MoS₂ showed good response values for adenine (A) and guanine (G) but poor values for cytosine (C), thymine (T), and uracil (U). Increasing the oxygen doping concentration to 4.16% improved the response values for all nucleobases and reduced the recovery time to less than 0.133 s at 500 Kelvin. Our results suggest that oxygen-doped MoS2 is a promising substrate for DNA/RNA sequencing applications.