A novel nanocomposite material C3F7-azo+/Ti4O92− was prepared as a sensor for the detection of ascorbic acid and uric acid

Abstract

A novel layered nanocomposite, C₃F₇-azo⁺/Ti₄O₉²⁻, was prepared using the stripping/restacking method with K₂Ti₄O₉ as the raw material and trans-[2-(2,2,3,3,4,4,4-heptafluorobutylamino) ethyl]-{2-[4-(4-hexyphenylazo) -phenoxy] ethyl}-dimethylammonium (hereinafter referred to as C₃F₇-azo⁺Br⁻) as the modifier. After modification on glassy carbon electrodes (GCE), it was used for simultaneous detection of ascorbic acid (AA) and uric acid (UA). The morphology and elemental composition of the nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). The electrochemical properties were measured and analyzed by differential pulse voltammetry (DPV), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Compared to single-component modified electrodes (K₂Ti₄O₉/GCE, C₃F₇-azo⁺/GCE), the layered nanocomposite modified electrode (C₃F₇-azo⁺/Ti₄O₉²⁻/GCE) exhibited a larger electrochemically active area (0.074 cm²), lower charge transfer resistance (94.0 Ω), and greater catalytic activity toward AA and UA. The detection limits were 0.39 μM for AA and 0.75 μM for UA, within the concentration ranges of 1.20–26.30 μM and 0.94–20.41 μM, respectively. The efficacy of C₃F₇-azo⁺/Ti₄O₉²⁻ was also demonstrated in real rabbit serum samples, with recoveries between 96.1% and 104.2%.