Integration of 6-Thioguanine Functionalized Molybdenum–Copper Bimetallic Nanoclusters With Fluorescence Spectroscopy for the Sensitive Detection of Uric Acid in Biofluids

In this paper, a single-step synthetic approach is presented for the development of bimetallic molybdenum-copper nanoclusters (Mo-CuNCs), shielded by a small molecule 6-thioguanine (6-TG). The Mo-CuNCs possessed a small size, high fluorescence, stable behavior, and good solubility in water. The 6-TG-Mo-CuNCs exhibit strong blue fluorescence emission at 410 nm after exciting at 330 nm as compared to its monometallic nanoclusters. Utilizing 6-TG-Mo-CuNCs superior biochemical stability, uric acid (UA) can be specifically detected as an oxidative stress biomarker using an inner filter effect mechanism. The probe demonstrated good sensing capability for detecting UA within the range of 0.09-5.00 μM and a detection limit of 0.237 μM. The method feasibility is further validated by quantifying UA in urine and plasma samples.