阳离子表面活性剂对电化学法测试牛奶中氯霉素残留量的影响

为探索用电化学方法检测生物样品中氯霉素残留的高灵敏度技术,本实验研究了阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)对氯霉素在玻碳电极上伏安行为的影响,实验结果表明,以0.02 mol/L高氯酸为支持电解质,在0.40~-0.60 V的范围内进行伏安扫描时,2×10-5mol/L CTMAB能显著提高氯霉素在-0.41 V处的还原峰电流。利用这种改进的电化学方法检测氯霉素的线性范围为0.0026~8 mg/L,检出限达到0.83μg/L。研究了缓冲液种类及其酸碱度及其它表面离子活性剂等对测试氯霉素的影响。

Effect of Cationic Surfactant on the Voltammetric Determination of Chloramphenicol Residue in Milk

Effect of cetyltrimethyl ammonium bromide (CTAB), a cationic surfactant, on the voltammetric determination of chloramphenicol at glass-carbon electrode (GCE) was investigated to explore techniques with high sensitivity for detecting the residue of chloramphenicol in biological samples. The results showed that 2 × 10⁻⁵ M CTAB could significantly improve the reductive peak current at the potential of –0.41 V, whereas, the scanning was performed in the range of 0.40 V–0.60 V using 0.02 mol perchloric acid as the supporting solution. Moreover, the linear range of this modified electrochemical method is from 0.0026 mg l⁻¹ to 8 mg l⁻¹ and the detecting limit is 0.83 μ g l⁻¹. Other conditions affecting the determination of chloramphenicol were also discussed in detail.