A novel electrochemical probe crafted from copper oxide nanoball-multiwalled carbon nanotube for valacyclovir detection in environmental and medicinal matrices

Growing global demand for antivirals with minimised adverse effects is eternally at the vanguard of infections. Although valacyclovir hydrochloride (VCV) is a safe antiviral, it may lead to dire side effects not only on the patients’ bodies but also on the environment if misused. Due attention is paid to optimizing the potency of the VCV, a novel electrochemical approach has been generated for fast and efficient detection of VCV’s residue in environmental water and patients' biofluids. Herein, VCV-highly sensitive platforms were crafted through direct decoration of copper oxide nanoballs (Cu₂O NBs) onto multiwalled carbon nanotube (MWCNT)-modified glassy carbon electrodes (GCEs). Cu₂O NBs and MWCNT combine to enhance electrical sensing capabilities. The copper oxide creates numerous active sites for surface interactions, while carbon nanotubes establish efficient pathways for electron transport. This combination improves detection sensitivity through enhanced electronic conductivity, abundant active sites, and extensive surface area. With expeditious response time and remarkable selectiveness, the fabricated Cu₂O/MWCNT/GCE probes were accurately traceable VCV within a broad range of concentrations from 0.5 to 65 μM. Parallel to a wide range of accuracy with proper sensitivity of 0.61 μA μM⁻¹, while benefiting from notable reproducibility and low detection limit (0.16 μM), Cu₂O/MWCNT/GCE probes are propitious for VCV-level detection in near-physiological pH conditions. Consequently, the precise Cu₂O/MWCNT/GCE sensing probes are up to trace VCV in not only human biofluids, but also environmental (river/ground waters) and pharmaceuticals with no sample pre-treatment.