Tunable Competitive Absorption-Induced Signal-On Photoelectrochemical Immunoassay for Cardiac Troponin I Based on Z-Scheme Metal–Organic Framework Heterojunctions

Recently emerged Z-scheme heterostructure-based immunoassays have presented new opportunities for photoelectrochemical (PEC) biosensing development. Here, we described a tunable signal-on PEC biosensor for the detection of cardiac troponin I (cTnI), which exploited a competitive absorption effect between Cu(II) ions and a Zr metal-organic framework (Zr-MOF) constructed on TiO