NH2-fMWCNT-titanium dioxide nanocomposite based electrochemical sensor for the voltammetric assay of antibiotic drug nadifloxacin and its in vitro permeation study

An electrochemical sensor is described for the determination of nadifloxacin (NF). A glassy carbon electrode (GCE) was modified with amino-functionalized multiwalled carbon nanotubes and titanium dioxide nanoparticles. The modified GCE was characterized by electrochemical impedance spectroscopy, cyclic voltammetry and scanning electron microscopy. The electro-oxidation of NF follows a pH-dependent irreversible behavior. The effects of pH value, scan rate, supporting electrolyte, accumulation potential and accumulation time were optimized. Under optimum conditions and at a typical working potential of 600 mV (vs. Ag/AgCl), the adsorptive stripping voltammetric response is linear in the 5 nM to 5.0 μM NF concentration range. The limit of detection is 1.69 × 10−10 M in acidic solution of pH 1. The selectivity was investigated in the presence of 1–1000-fold concentrations of potentially interfering agents. Recoveries from cream formulations spiked with NF were performed to study precision and accuracy. •Electroanalytical behavior of Nadifloxacine as an antibiotic drug was investigated in details•A new sensor was developed for Nadifloxacine by NH2-fMWCNT-Titanium Dioxide Nanocomposite modified glassy carbon electrode•Modified electrode surface was characterized with several techniques.•Analytical validation parameters were studied.