Two-electrode Sensor System for Rapid Detection of Sulfonamides by Applying the Nafion-Carboxyl Multiwalled Carbon Nanotubes Powder Microelectrode

摘要

A powder microelectrode (PME), embedded with Nafion-carboxyl multiwalled carbon nanotubes(MWCNTs), was prepared for selective and sensitive determination of sulfonamides. The effects ofexperimental parameters on the response of electrode such as pH of buffer, scan rate were optimized.Under optimal conditions, the proposed PME can greatly improve the determination sensitivity. In a-5Britton-Robison (BR) buffer solution (pH 2.0), the linear response range for detection of 1.010 -4 2 2 mol/L to 1.010 mol/L of sulfonamide (R =0.984), sulfadiazine (R =0.993), sulfamethazine2 2 -6 -6 (R =0.987), sulfamethoxazole (R =0.982) and the detection limits of 2.6910 mol/L, 3.1010-6 -6 mol/L, 8.9410 mol/L and 5.7910 mol/L, respectively. The recoveries were in the range of87~106% with RSD% and the Nafion-MWCNTs PME performed excellent repeatability anddurability. The proposed sensor was successfully applied for the determination of SAs in real samplesand might offer feasibility and applicability for other determination of more complex sulfonamidescompounds.