Abstract
γHydroxybutyric acid (GHB), a depressant of the central nervous system, is commonly used illegally and in drug-facilitated crimes; therefore, it is crucial to develop reliable and fast methods for detecting GHB. This study uses DFT theory to design and evaluate the performance of electrochemical and colorimetric nanosensors based on fullerene and its forms of doping with boron and zinc for GHB detection. The calculation results (bond length, HOMO-LUMO energy gap, infrared spectra and UV-visible absorption spectra) for C(60) showed very good overlap with experimental results in other literature, indicating the validity of the computational method used in this work. Several analyses (such as electronic structure calculations, adsorption energy evaluation, charge-transfer analysis, NBO, NCI/RDG, ELF, LOL, QTAIM, conductivity, recovery time, and optical response analyses) were performed to investigate the sensor performance. After comparing these results, Boron-Doped C(60) (BC(59)) was found to be the best candidate for electrochemical sensing of GHB based on conductivity modulation & charge transfer behavior. In contrast, pure C(60) with the largest spectral shift (in the visible range) was introduced as a suitable candidate for colorimetric measurement. Zinc-doped C(60) adsorbs GHB best (based on adsorption properties), making it suitable for GHB removal and adsorption in purification applications. Overall, this computational study makes experimental efforts more targeted by qualitatively assessing sensor performance and reducing trial and error, and provides clear guidance for future experimental validation and development of efficient GHB detection platforms.