Eu(III) encapsulation strategy to construct intelligent ratiometric luminescent sensor for efficient detection of phenylglyoxylic acid biomarker in bodily fluids

Herein, a desirable MOF-based luminescent sensor of Eu3+@ZnMOF is fabricated through post-synthesis strategy. Based on response differences of the inherent monitoring signal at 442 nm and the secondary monitoring signal at 699 nm introduced by encapsulating Eu3+ ions, the prepared Eu3+@ZnMOF displays great superior as a ratiomertic luminescent sensor with high sensitive and selective, rapid response time (less than 1 min), superior detection limit (3.89 ng & sdot;mL- 1), and favorable recyclable performance (at least 6 cycles) in detecting phenylglyoxylic acid (PGA) biomarker over other urine and serum species. Furthermore, Eu3+@ZnMOF also demonstrates exceptional detectability and remarkable reliability in tracing PGA levels within actual serum and urine samples. On the basis of PGA levels controlled luminescence changes of Eu3+@ZnMOF under UV light, an intelligent detection platform is developed by integrating tandem combinational "AND" logic gates to achieve more convenient and intuitive detection of PGA levels in body fluids. Besides, photoinduced electron transfer and internal filtering effect are demonstrated to be responsible for the luminescence sensing. This work not only offers a validated strategy for the design of MOFs-based ratiometric luminescent sensors, but also presents an approach in efficient, rapid, and intelligent detection of biomarkers in body fluids.