Test Center, Wellhope Agri-Tech Joint Stock Co., Ltd, Shenyang, Liaoning Province, PR China.
Technical Research and Development Department, Shenyang Fame Biotechnology Co., Ltd, Shenyang, Liaoning Province, PR China.
J Chromatogr B Analyt Technol Biomed Life Sci. 2020 Sep 1;1152:122253. doi: 10.1016/j.jchromb.2020.122253. Epub 2020 Jun 21.
Olaquindox, oxytetracycline and chlorotetracycline were widely used in feed as antibiotics and growth promoter to improve feed conversion efficiency and increase the rate of weight gain for animals. However, the use of these antibiotics in feed was gradually prohibited because of concerns about contamination and resistance in animals. A quantitative and confirmatory method for determining the presence of olaquindox, oxytetracycline and chlorotetracycline in feed by high performance liquid chromatography equipped with ultraviolet detector in series with fluorescence detector (HPLC-UVD-FLD) was developed, optimized, and validated in three different matrices (compound, concentrated and premix feed). The analytes extraction was performed with a mixture of acetonitrile and 0.1 mol/L ethylenediamine tetraacetic acid disodium-Mcllvaine buffer (1:4, v/v) by one step sample preparation procedure. The validated method presented a broad linear range and good linearity with weighted least square method. The decision limit of the analytes ranged from 0.61 to 0.77 mg/kg for olaquindox, 0.90 to 1.2 mg/kg for oxytetracycline and 1.3 to 2.0 mg/kg for chlorotetracycline. The average recovery values found in intermediate precision conditions were ranged from 88.0 to 99.7% for olaquindox with RSD lower than 11.1%, from 84.4 to 99.0% for oxytetracycline with RSD lower than 9.6%, from 83.8 to 97.5% for chlorotetracycline with RSD lower than 10.0%. By Youden test and bottom-up method, the method was proved to be sufficiently robust and had a small uncertainty for different concentration levels. The developed method was successfully utilized for commercial feed samples to monitor complex cross contamination and residue conditions. Online synchronous derivation and separation using ultraviolet detector in series with fluorescence detector can effectively prevent false positive of chlorotetracycline in feed caused by vegetable meal. Since olaquindox, oxytetracycline and chlorotetracycline are widely used in feed, the developed method provide an important and analytical tool for the simultaneous identification and quantification of them in feed to monitor its risk of cross contamination and excessive content.
奥拉喹多、土霉素和金霉素曾作为抗生素和生长促进剂被广泛应用于饲料中，以提高饲料转化率和动物的增重率。然而，由于担心动物体内的污染和耐药性问题，这些抗生素在饲料中的使用逐渐被禁止。本研究建立了一种通过高效液相色谱串联紫外检测器和荧光检测器（HPLC-UVD-FLD）定量和确证饲料中奥拉喹多、土霉素和金霉素的方法，并在三种不同基质（复合饲料、浓缩饲料和预混料）中对该方法进行了优化和验证。采用乙腈和 0.1 mol/L 乙二胺四乙酸二钠-柠檬酸缓冲液（1:4，v/v）的混合液通过一步样品制备程序提取分析物。该方法采用加权最小二乘法进行线性回归，呈现出较宽的线性范围和良好的线性关系。三种分析物的检测限（CCα）分别为 0.61-0.77mg/kg （奥拉喹多）、0.90-1.2mg/kg（土霉素）和 1.3-2.0mg/kg（金霉素）。在中间精密度条件下，平均回收率在 88.0%-99.7%之间，相对标准偏差（RSD）低于 11.1%（奥拉喹多），84.4%-99.0%（土霉素），RSD 低于 9.6%，83.8%-97.5%（金霉素），RSD 低于 10.0%。通过 Youden 测试和自下而上的方法，证明该方法在不同浓度水平下具有足够的稳健性和较小的不确定性。该方法成功地应用于商业饲料样品中，监测复杂的交叉污染和残留情况。使用紫外检测器串联荧光检测器进行在线同步衍生和分离，可以有效防止饲料中由于植物性饲料的存在而导致的金霉素假阳性。由于奥拉喹多、土霉素和金霉素在饲料中广泛使用，因此该方法为同时识别和定量饲料中的这些物质提供了一个重要的分析工具，以监测其交叉污染和过量含量的风险。
