A DFT insight into the potential of cycloparaphenylenes as efficient sensors for detecting Paracetamol

Paracetamol (PCT) frequently contaminates natural water sources, posing potential risks to both human health and ecosystems. This study presents a computational investigation into the sensing capabilities of methylene-bridged [n]cycloparaphenylene ([n]MCPP, where n= 6, 8, and 10) nanorings for the detection of paracetamol using density functional theory (DFT) calculations. It was found that the stability of PCT@[n]MCPP complexes increases with the size of the [n]MCPP nanorings. The energy gap of the [n]MCPP nanorings is significantly influenced by the presence of the PCT drug, with the most substantial change (-44.79%) observed for the PCT@⁶MCPP complex. Additionally, non-covalent interaction (NCI) analysis reveals that van der Waals forces predominantly govern the interactions between paracetamol and the [n]MCPP nanorings. The calculated short recovery times and favorable sensor response factors of the PCT@[n]MCPP complexes at 298 K suggest that [n]MCPP nanorings can be used as promising materials for the detection of paracetamol. These findings underscore the potential of methylene-bridged [n]cycloparaphenylene nanorings as valuable candidates for identifying and eliminating PCT drug from the environment.