1：Experimental Design and Method Selection:

The study involved the hydrothermal growth of ZnO nanowire arrays (NWs) on FTO substrates, modification with Au nanoparticles (NPs) and CdS quantum dots (QDs), and the assembly of an aptamer for E. coli O157:H7 detection. The PEC biosensor was developed by synergizing the enhanced light absorption and charge separation properties of the hybrid structure.

2：Sample Selection and Data Sources:

E. coli O157:H7 and S. aureus were cultured in sterile Luria-Bertani (LB) media. The number of bacteria was quantified by counting colony forming units (CFU).

3：List of Experimental Equipment and Materials:

Field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV-vis absorption spectra, X-ray photoelectron spectrometer (XPS), CHI660D electrochemical workstation, Xe lamp with 350 nm cut-off filter.

4：Experimental Procedures and Operational Workflow:

The ZnO NWs were modified with Au NPs and CdS QDs, followed by aptamer assembly. The PEC measurements were performed using a homemade PEC system equipped with an Xe lamp. The photocurrent was measured at a constant potential of 0 V (vs Ag/AgCl) in PBS containing ascorbic acid.

5：Data Analysis Methods:

The photocurrent responses were analyzed to determine the detection limit and linear range for E. coli O157:H7. The selectivity, stability, and reproducibility of the aptasensor were also evaluated.