Electrochemical fabrication of TiO2 nanoparticles/[BMIM]BF4 ionic liquid hybrid film electrode and its application in determination of p-acetaminophen

A water soluble ionic liquid, 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM]BF4), was incorporated into TiO2 nanoparticles to fabricate a hybrid film modified glassy carbon electrode (nano‐TiO2/[BMIM]BF4/GCE) through electrochemical deposition in a tetrabutyltitanate sol solution containing [BMIM]BF4. The obtained nano‐TiO2/[BMIM]BF4/GCEs were characterized scanning electronic microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). Electrochemical behaviors of p‐acetaminophen at the nano‐TiO2/[BMIM]BF4/GCEs were thoroughly investigated. Compared to the redox reaction of p‐acetaminophen using an unmodified electrode under the same conditions, a new reduction peak was observed clearly at 0.26 V with the modified electrode. In addition, the peak potential for the oxidation of p‐acetaminophen was found to shift negatively about 90 mV and the current response increased significantly. These changes indicate that the nano‐TiO2/[BMIM]BF4 hybrid film can improve the redox reactions of p‐acetaminophen in aqueous medium. Under optimum conditions, a linear relationship was obtained for the p‐acetaminophen solutions with concentration in the range from 5.0 × 10− 8 to 5.0 × 10− 5 M. The estimated detection limit was 1.0 × 10− 8 M (S/N = 3). The newly developed method was applied for the determination of p-acetaminophen in urine samples.