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.