毛细管电泳用于水产品中五种抗生素的同时测定

Simultaneous Determination of Five Residual Antibioticsin Seafood by Capillary Electrophoresis

用毛细管电泳 紫外检测法同时测定水产品中的四环素(TC)、金霉素(CTC)、土霉素(OTC)、多西环素(DC)及氯霉素(CAP)的含量.研究了缓冲体系的酸度、浓度、添加剂、分离电压、进样时间以及温度等条件对分离的影响,得到了电泳的最优条件.在278nm波长处,分离电压为22kV,20mmol/L磷酸氢二钠 10mmol/L柠檬酸(pH值2.8,含0.25mmol/LNa2EDTA和体积分数为4.0%的吐温 80)运行缓冲液下,上述5种组份在25min内得到完全分离.5种抗生素的质量浓度和电泳峰面积在2.5～300.0mg/L和10.0～300.0mg/L范围内呈现良好的线性,TC、CTC、OTC、DC和CAP的相关系数(r)分别为0.9996、0.9992、0.9993、0.9984、0.9987,检测下限为0.5～1.5μg/mL.该方法灵敏度高,重现性好,操作简便,并已成功用于水产品鲫鱼中的5种抗生素残留的检测.

A method based on capillary electrophoresis with ultraviolet detection was developed for simultaneous determination of tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC), doxycycline (DC) and chloramphenicol (CAP) residues in seafood. The effects of some important factors such as additive, acidity and concentration of running buffer,separation voltage, injection time and temperature were investigated to acquire the optimum condition. In 278 nm wavelength, the five analytes could be well separated within 25 min on a 65 cm length capillary at the separation voltage of 22 kV in 20 mmol/L Na2HPO4-10 mmol/L citric acid (pH 2.8) with additive of 0.25 mmol/L Na2EDTA and volume ratio is 4.0% Tween-80. The calibration curves of TC、CTC、OTC、DC and CAP were linear by plotting the peak aera against the sample concentration over the range from 2.5 mg/L to 300.0 mg/L and 10.0 mg/L to 300.0 mg/L. The correlation coefficiency were 0.999 6, 0.999 2, 0.999 3, 0.998 4, 0.998 7 for TC、CTC、OTC、DC and CAP, respectively. The detection limits were 0.5 μg/mL for TC, 0.5 μg/mL for CTC, 0.5 μg/mL for OTC ,1.5 μg/mL for DC and 1.0 μg/mL for CAP(S/N=3). This method also could be applied to analyze the other kinds of samples for the residues of the five antibiotics.