纳米TiN碳糊电极对青霉素的电化学检测

以纳米氮化钛(TiN)为电活性物质,制备了用于检测青霉素的纳米TiN修饰碳糊电极.研究了该碳糊电极中石墨与纳米TiN的质量比、电极面积、溶液pH值及缓冲容量等因素对青霉素检测效果的影响.结果表明,在优化的条件(石墨与TiN的质量比为2∶1,电极面积为1 mm~2,溶液pH值为7.2以及缓冲容量为20 mmol/L KH_2PO_4)下,该电极检出限为2×10~(-5)mol/L,线性检测范围为4×10~(-5)~3.2×10~(-3)mol/L.利用Zeta电位及交流阻抗的方法,揭示了纳米TiN碳糊电极检测青霉素的机理为纳米TiN对青霉素的特异性吸附.纳米TiN碳糊电极展现出良好的稳定性、选择性和重复性,在青霉素检测领域具有广阔的应用前景.

Electrochemical Detection of Penicillin Based on Titanium Nitride Nanoparticles Carbon Paste Electrode

A titanium nitride nanoparticles(TiN) modified carbon paste electrode was prepared to detect penicillin.The effects of the mass ratio of titanium nitride to graphite, electrode area, pH value and concentration of the buffer solution on the detection of penicillin were studied.With the optimized conditions, the electrode offered a minimum detection limit of 2×10-5 mol/L and a linear dynamic range of 4×10-5-3.2×10-3 mol/L.Moreover, the detection mechanism was an adsorption action, which was revealed by the zeta potential and electrochemical impedance spectroscopy characterizations.Overall, the TiN modified carbon paste electrode shows good stability, high selectivity, excellent repeatability and a promising application in penicillin detection.