Supramolecular phenolic network-engineered C–CeO2 nanofibers for simultaneous determination of isoniazid and hydrazine in biological fluids

Abstract

Electrochemical sensing provides a powerful technological means for the therapeutic drug monitoring of drug-resistant tuberculosis but requires a functionalized electrode to capture the analytes and catalyze their redox reactions. Herein, we construct a nickel–tannic acid supramolecular network (Ni–TA) on the surface of electrospun-derived C–CeO2 nanofiber for the sensitive and simultaneous detection of isoniazid (INZ) and hydrazine (HYD). Mechanistic investigations demonstrate that Ni–TA is electronegative and hydrophilic, thus facilitating an efficient mass and electron transfer. Ni–TA/C–CeO2 has higher adsorption rate constants (0.091 g mg–1 h–1 for INZ, and 0.062 g mg–1 h–1 for HYD) than native C–CeO2 (0.075 g mg–1 h–1 for INZ, and 0.047 g mg–1 h–1 for HYD). Moreover, Ni–TA/C–CeO2 (56 Ω) has lower charge transfer resistances than C–CeO2 (417 Ω). Ni–TA/C–CeO2 performs low detection limits and wide linearity ranges for INZ (0.012 µmol/L and 0.1–400 µmol/L, respectively) and HYD (0.008 µmol/L and 0.015–1420 µmol/L, respectively), coupled with high selectivity, cycle stability and reproducibility. This research demonstrated the promising applications of Ni–TA/C–CeO2 by analyzing human-collected plasma and urine samples.