A fluorescent ELISA based on the enzyme-triggered synthesis of poly(thymine)-templated copper nanoparticles

Inspired by the ALP-triggered hydrolysis of the substrate ascorbic acid 2-phosphate as well as the product ascorbate-controlled generation of polyT–CuNPs with bright red fluorescence, we have developed a novel, selective and sensitive fluorescence turn-on assay for ALP activity sensing. Based on the conventional ELISA platform and commercially available antibody–ALP conjugates, an unconventional fluorescent ELISA system has been rationally developed and successfully applied in the quantitative measurement of model antigen proteins using fluorescence spectroscopy and a naked-eye readout under ultraviolet light.