1：Experimental Design and Method Selection:

Synthesis of SnO2 cocatalyst loaded onto mesoporous TiO2 nanoparticles using a combination of sol-gel method followed by thermal decomposition. Fabrication of the nanocomposite over a glassy carbon electrode (GCE) for electrochemical measurements.

2：Sample Selection and Data Sources:

Use of pharmaceutical tablets containing vitamin B6, prepared by grinding and dissolving in phosphate buffer.

3：List of Experimental Equipment and Materials:

Instruments include X-ray fluorescence (XRF, EDX-720, Shimadzu), X-ray diffractometer (XRD, D5000 diffractometer, Siemens), high resolution transmission electron microscopy (HR-TEM, FEI TITAN G2 80-300), X-ray photoelectron spectroscopy (XPS, Thermo Scientific Escalab 250Xi), BET surface area analyzer (Micromeritics ASAP 2020), and electrochemical workstation (PGSTAT 12, AUTOLAB). Materials include titanium tetra isopropoxide (TTIP), tin (IV) acetate, isopropyl alcohol, citric acid, phosphate buffer, and others from Sigma-Aldrich and Sisco research laboratories.

4：Experimental Procedures and Operational Workflow:

Preparation of mesoporous TiO2 via sol-gel method, followed by grinding with tin acetate and calcination to form SnO2-TiO2 nanocomposite. Electrode modification by drop-casting the nanocomposite suspension on GCE. Electrochemical measurements using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) in a three-electrode system.

5：Data Analysis Methods:

Use of Randles-Sevcik equation for surface area calculation, and standard calibration curves for quantification.