Preparation of molecularly imprinted ratiometric fluorescent probe and test strip for visual detection of methyl methanesulfonate.

Methyl methanesulfonate (MMS), a genotoxic impurity, poses potential risks to human health due to its residues in pharmaceutical production, making its detection crucial. This study was based on the property that MMS can enhance the blue fluorescence of Eu-MOF. For the first time, we developed a molecular imprinting ratio fluorescent probe and test strip. The color change of the probe solution and test strip from pink to blue enables specific visual detection of MMS. Under optimal conditions, the fluorescence intensity ratio (I453/I588) exhibited a good linear relationship with MMS concentration in the range of 1.0-100.0 μM, with a detection limit of 87.5 nM. Studies on sensing mechanism have revealed that the coordination between Eu and the sulfonic acid in MMS resulted in a weakened interaction between the ligand 2-aminoterephthalic acid and Eu metal clusters, thereby inhibiting photoinduced electron transfer (PET) and ultimately leading to enhanced fluorescence. Notably, this work provides a novel method for fluorescence-based quantitative detection of MMS in pharmaceutical wastewater, soil, and simulated human serum, as well as on-site visual detection using test strips.