Determination of Norfloxacin Using a Tetraoxocalix[2]arene[2]-triazine Covalently Functionalized Multi-walled Carbon Nanotubes Modified Electrode

This paper presents a sensitive voltametric procedure for the determination of norfloxacin (NF) by a tetraoxocalix[2]arene[2]triazine (TOCT) covalently functionalized multi-walled carbon nanotubes (MWCNTs) modified electrode. The electrochemical sensing of NF was investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Through a combination of the excellent selective recognition of TOCT and the outstanding electronic properties of MWCNTs, this electrochemical sensor shows excellent sensitivity and high selectivity for an electrochemical detection of NF. The stripping response is highly linear (R = 0.996) over the NF concentration range of 0.5 - 8.0 mu M with the LOD of 0.1 mu M. The fabricated sensors were successfully applied for quantitative detection of NF in pharmaceutical formulations and human urine samples. A high anti-interference ability to common interferences and satisfactory results were obtained. This is expected to play a huge potential in the real-time monitoring of NF in clinical applications.