Tetranuclear Cluster-Based Luminescent Metal-Organic Framework as Robust Chemical Sensor toward Phenylglyoxylic Acid Biomarker in Bodily Fluids

Abstract Phenylglyoxylic acid (PGA) is widely established as a core urinary biomarker for assessing human exposure to styrene (SM) and ethylbenzene (EB), and developing reliable luminescent sensors carries critical practical significance for occupational health monitoring. In this work, a tetranuclear cluster-based 3D CdMOF has been solvothermally constructed by employing the rigid aromatic linker of 2,4-bis(2,5-dicarboxyphenyl)benzene-1,5-dicarboxylic acid (H6THA). Taking advantage of its robust structural stability and intrinsic luminescence, the fabricated CdMOF functions as a high-performance PGA luminescent sensor with exceptional sensitivity, superior anti-interference, and low detection limits. Mechanistic explorations demonstrate that the distinct luminescence quenching behavior toward PGA is primarily dominated by the synergistic effect between photo-induced electron transfer (PET) and competitive absorption (CA), which lays a solid theoretical foundation for subsequent performance optimization. This work delivers an actionable strategy for developing stable cluster-based MOFs as high-efficiency luminescent sensors toward trace biomarkers in biological fluids.