Multifunctional SAzymes-in-MOF Hybrids: Single-Atom Cu-Doped Carbon Dots@Zr-MOF Polyhedra for Highly Sensitive PEC-RGB Dual-Mode Assay of ATP

-hydroxysuccinimide (NHS) cross-linking reaction. When ATP was present, the destruction of PCN-224 occurred due to the formation of Zr-O-P bonds, releasing SA Cu-CDs from SA Cu-CDs@PCN-224 hybrids. The released SA Cu-CDs triggered a turn-on blue signal through a catalytic chromogenic reaction in the RGB mode, while the destruction of PCN-224 resulted in a turn-off photocurrent signal in the PEC mode. Hence, a highly sensitive and reliable assay of ATP was carried out with wide linear response ranges (0.5-2000 nM for PEC and 5-2000 nM for RGB) and low detection limits (0.12 nM for PEC and 1.08 nM for RGB). The innovative design of SAzymes-in-MOF hybrids provides a new preparation strategy of multifunctional probes for PEC-RGB dual-mode assays, and the developed SA Cu-CDs@PCN-224 hybrids and a PEC-RGB dual-mode biosensing platform may have great potential application in bioanalysis and disease diagnostics.