Bovine Serum Albumin-Capped Fluorescent Copper Nanocluster Incorporated with 2D-Molybdenum Disulfide Nanosheets as a FRET-Based Immune Probe for the “Turn-On” Detection of cTnT

Cardiovascular disease is the primary cause of mortality worldwide, as stated by the World Health Organization. We utilized the red fluorescence emitted by copper nanoclusters (CuNCs) to detect cardiac Troponin T (cTnT). We designed a fluorescent probe to detect cTnT using an on–off–on technique. The cTnT antibody was coupled on the surface of a bovine serum albumin-capped CuNC (Ab-BSA©CuNC) MoS2 nanosheet, efficiently quenching the luminescence of Ab-BSA©CuNCs due to their high affinity and binding interaction by establishing an Ab-BSA©CuNC/MoS2 platform. The luminescence of Ab-BSA©CuNCs was restored due to the antigen–antibody interaction. With a detection limit of 9.4 pg/mL, a linear relationship between the luminescence intensity concentrations of cTnT was observed in the 0.161–1.57 ng/mL ranges. Additionally, the efficacy of the developed technique to measure cTnT in blood serum samples was evaluated, and it exhibited a good recovery percentage.