Fig. 4
From: Quantum dot biosensors for highly sensitive and multiplex detection in biomedical diagnostics
Schematic illustration of the fabrication and detection mechanism of a photoelectrochemical (PEC) immunosensor for cTnI detection using Ag@Cu₂O submicron particles. (Top) Functionalization of Ag@Cu₂O particles with detection antibodies (Ab₂) via APTES modification followed by EDC/NHS coupling. (Bottom) Stepwise assembly of the sensing platform on an ITO/TiO₂ substrate, including deposition of CdS, immobilization of primary antibodies (Ab₁), blocking with BSA, antigen binding, and subsequent attachment of Ab₂-functionalized Ag@Cu₂O particles. Figure adapted and modified from [74]