Application of biphenylene nanosheets for metronidazole detection

Abstract

The goal of this study is to explore whether biphenylene nanosheet (BPNS) and its doped counterparts (B- and Al-BPNS) can be used as sensors for metronidazole (MN) using the density functional theory. The study used the B3LYP functional along with the 6–31 + G(d) and 6–31++G(d,p) basis sets and considered both gas and implicit solvent phases. The most stable configuration of pristine and doped BPNS:MN complexes was identified by optimizing the geometry of all probable conformations obtained from the molecular electrostatic potential plots of nanosheets and the drug molecule. The adsorption of MN on the surface of pristine BPNS resulted in an adsorption energy (Eads) of −18.3 and −16.9 kcal.mol−1 (first and second digits indicate the data obtained from the 6–31 + G(d) and 6–31++G(d,p) basis sets, respectively). The electrical properties of pristine BPNS, identified by the highest occupied and the lowest unoccupied molecular orbitals (HOMO and LUMO, respectively), remained unchanged upon adsorption of MN. The predicted time for desorption of the MN drug from the BPNS surface is about 2.5 × 10−3 and 2.3 × 10−4 s. The study suggests that pristine BPNS is not a suitable carrier and biosensor for MN drug molecules. Therefore, the doping technique was explored to enhance the sensing features of BPNS towards the MN molecule. The results showed that the Eads value of B-BPNS is about −20.6 and −20.1 kcal.mol−1, which is higher than that of pristine BPNS. However, the electrical properties of B-BPNS are not sensitive to the presence of MN molecules. The predicted time for desorption of the MN drug from the surface of B-BPNS is about 1.2 × 10−1 and 5.2 × 10−2 s. Adsorption of MN on the surface of Al-BPNS causes an adsorption energy of −25.0 and –23.6 kcal.mol−1. However, the HOMO-LUMO energy gap decreased by approximately 26.3 % and 24.5 %, upon Al doping, which is favorable from a sensing point of view. The predicted time for desorption of the MN drug from the Al-BPNS is about 2.0 × 102 and 1.9 × 101 s. These findings suggest that Al-BPNS could be used as a suitable carrier and biosensor for MN drug molecules.