A Comprehensive Sensitivity Analysis of Adenine Nucleobase on Pristine and Platinum Decorated ZnO Nanosheets: An Interaction Dynamics

The current study compares the ability of pristine ZnO nanosheets and platinum (Pt) doped ZnO nanosheets to sense adenine (A) nucleobase using a first-principle computational method with Gaussian 09W and Gauss View 6.0 software. Adenine, being a fundamental nitrogenous base, was chosen as the adsorbed molecule for both types of nanosheets. This created two systems viz. adenine adsorbed pristine ZnO nanosheet system (system-I), and adenine adsorbed Pt-decorated ZnO nanosheet system (system-II). The adsorption and interaction between the considered molecule and the sensing surface were analyzed using various electronic characteristics such as Mulliken charge analysis, Molecular Electrostatic Potential (MEP), Density of States (DOS), the Lowest Unoccupied Molecular Orbital (LUMO), and the Highest Occupied Molecular Orbital (HOMO). It was observed that the pristine ZnO nanosheet exhibited better reactivity, resulting in a strong adsorption energy (−1.784 eV) compared to the Pt doped ZnO nanosheet with an adsorption energy of −1.253 eV. However, the Pt decorated ZnO nanosheet demonstrated moderate binding distance (2.0236 A) with adenine compared to that of the pristine ZnO nanosheet (3.0301 A). This research analysis outlined the importance of proper detection and pairing of adenine in the DNA leading to healthy life processes. Moreover, the combination of charges in the electronic structure, molecular orientations, and surface defects might be the probable reasons behind the reduced reactivity and sensing ability of the ZnO nanosheet towards adenine upon introducing platinum dopant.