1：Experimental Design and Method Selection:

The study designed an impedance sensor using gold interdigitated electrodes on a tungsten oxide thin film. The sensor was functionalized with vancomycin for specific capture of Gram-positive bacteria. Impedance spectroscopy was used for detection, with characterization techniques including XRD, FESEM, AFM, FTIR, and SEM to confirm material properties and functionalization.

2：Sample Selection and Data Sources:

Bacterial strains included Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 9144, Pseudomonas aeruginosa ATCC 14886, Bacillus subtilis ATCC 6633, Pseudomonas ovalis NRRL B-85, Pseudomonas fluorescens NCIM, Bacillus licheniformis NRRL 1001, and Bacillus polymyxa DSM 366. Cells were cultured in Luria Broth, pelleted, and resuspended in PBS or other media for experiments.

3：Cells were cultured in Luria Broth, pelleted, and resuspended in PBS or other media for experiments. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: Equipment included RF sputtering system for W deposition, furnace for WO3 formation, lithography tools for patterning, UV-Vis spectroscopy (Perkin Elmer), XRD (Rigaku Ultima IV), FESEM (JEOL), FTIR (Nicolet iN10, Thermofisher Scientific), EDX (Hitachi Tabeltop Microscope Model TM 3000), SEM (Zeiss EVO 50), AFM (Innova, Bruker), impedance analyzer (Biologic SP150), ultrasonicator (Vibra-cell, SONICS), and centrifuges. Materials included silicon wafers with SiO2, tungsten, gold, chromium, vancomycin, piranha solution, ethanol, PBS, FBS, NaCl, bacterial culture media, and redox solutions.

4：Experimental Procedures and Operational Workflow:

Fabrication involved depositing W on SiO2/Si, oxidizing to WO3, patterning IDE structures via lithography and Cr/Au deposition. Functionalization included cleaning with piranha solution, incubating with vancomycin, and rinsing. Bacterial samples were prepared, applied to the sensor, and impedance measured in redox solution with frequency sweep. Viability tests used ultrasonication and plating.

5：Data Analysis Methods:

Impedance data were analyzed using Bode and Nyquist plots, equivalent circuit modeling with Powell algorithm in EIS spectrum analyzer, and statistical methods for LOD calculation. FTIR, XRD, and microscopy data were interpreted for material and functionalization confirmation.