Highly sensitive chemosensor for detection of methamphetamine by the combination of AIE luminogen and cucurbit[7]uril

Abstract Methamphetamine (METH) abuse has become a global problem, and new strategies for rapid and sensitive detection of METH are in urgent need. Herein, a novel technique is developed for highly sensitive detection of METH in solution with broad concentration by the assembly of AIE luminogen of tetrakis(4-(pyridin-4-yl)phenyl)ethene (TPPE) and cucurbit[7]uril (CB[7]). The 1H NMR and isothermal titration calorimetry (ITC) characterizations confirm that TPPE and CB[7] are self-assembled in a ratio of 1:4. While, the interaction of CB[7] with METH exhibits a binding ratio of 1:1 and stronger binding ability than with TPPE. Based on the competitive binding affinity, CB[7]⊃TPPE could be used as a chemosensor to detect METH in solution, which exhibits remarkable advantages such as rapid response, high sensitivity and low limit of detection (LOD). When the concentration of METH solution is larger than 40 μM, the enhancement of fluorescence intensity and change of fluorescent colour could be directly observed upon UV irradiation. When the METH solution concentration is higher than 10 μM, we can use our fabricated test strips to rapidly and visibly detect. If above detections do not work, we can measure the PL spectra of the sensing system, which shows a LOD as low as 0.43 μM. This unique CB[7]⊃TPPE based chemosensor is potentially applicable in real-time and visual detection of METH in solution and provides a powerful platform for preventing chemical solvent transport.