Self-assembled aggregation-induced emission supramolecular probe for sensitive temozolomide detection and intracellular imaging.

Temozolomide (TMZ) is a first-line chemotherapy drug for treating malignant glioblastoma but faces challenges due to its short plasma half-life and limited brain distribution. There is a need for a more efficient, cost-effective, and sensitive method for monitoring TMZ in clinical settings. This work presents a novel fluorescent probe based on the host-guest interaction of cucurbit[7]uril (CB[7]) and aggregation-induced emission molecule 1,1,2,2-tetra(biphenyl-4-yl)ethene (TTPE) for trace-level detection of TMZ in serum. The CB[7]@TTPE nanoprobe demonstrated high sensitivity, with a detection range of 1-20 μg/mL and a limit of detection of 0.25 μg/mL. Comprehensive characterization by ITC, FT-IR, NMR, UV-vis, and fluorescence spectroscopy confirmed the sensing behavior of the probe. The system exhibited excellent selectivity for TMZ and was successfully applied to serum samples with good recovery rates. In addition, the probe enabled fluorescence imaging of TMZ in human glioma cells (U87 and T98G), making it suitable for monitoring of drug distribution in cellular environments. The self-assembled CB[7]@TTPE probe provides a highly sensitive and selective method for TMZ detection in biological fluids. Its strong fluorescence and water solubility offer promising potential for both clinical diagnostics and drug resistance monitoring in cancer therapy.