超高效液相色谱-串联质谱法检测婴幼儿辅助食品中多种兽药残留

生产婴幼儿辅助食品的原辅料中常常含有鱼类、肉类、肝类等动物性组织,存在兽药残留的风险,为了更加全面地对这类产品进行安全监管,研究并开发了同时检测婴幼儿辅助食品中6大类(喹诺酮类、磺胺类、大环内酯类、硝基咪唑类、氯霉素类和抗病毒类)50种抗生素和抗病毒类兽药残留的超高效液相色谱-三重四极杆质谱法(UPLC-MS/MS)。样品采用酸化乙腈超声提取,提取液经新型的脂质增强型Captiva EMR-Lipid固相萃取柱净化,浓缩复溶后采用流动相乙腈和0.1%(v/v)甲酸水溶液,经C18柱梯度洗脱分离,电喷雾多反应监测(MRM)模式检测,基质匹配外标法定量。结果显示,该方法50种兽药在0.5~50 μg/L范围内线性关系较好,相关系数均不低于0.995,方法检出限为0.03~0.70 μg/kg,定量限为0.09~2.33 μg/kg。50种化合物在不同基质中,添加5和50 μg/kg两个加标水平进行试验,平均回收率为64.37%~119.3%,相对标准偏差均小于15%。将该方法应用于14份国产和6份进口的婴幼儿辅助食品检测,结果显示,1份进口肉类婴幼儿辅助食品中检出磺胺喹噁啉、磺胺二甲嘧啶和替米考星。该方法简单快速,灵敏度和准确度高,样品量消耗少,适用于婴幼儿辅助食品中多种兽药残留的检测。

Determination of multi-veterinary drug residues in complementary foods for infants and young children by ultra performance liquid chromatography-tandem mass spectrometry

Special attention must be paid to children and infants because health issues stemming from a poor immunologic system and low weight make them a vulnerable risk group. Complementary foods for infants and young children, which are a class of special dietary foods, are essential transitional foods for infants from lactation to adaptation to ordinary food. Some complementary foods for infants and young children are of animal origin such as fish, meat, and the liver, which may contain veterinary drug residues. Veterinary drugs are usually small-molecular-weight chemicals that are essential for treating infections, increasing production, and improving animal husbandry. However, abuse of these substances can provoke transfer to the food chain, leading to negative consequences for humans, especially infants and young children. For a more comprehensive safety supervision of infant supplementary foods, a method based on ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and used for the determination of 50 antibiotics and antivirals (grouped into six categories: fluoroquinolones, sulfonamides, macrolides, nitroimidazoles, chloramphenicols, and antivirals) in complementary foods for infants and young children. The matrix of complementary foods for infants and young children is complex and contains a large number of proteins and lipids, which poses a serious challenge for sample pretreatment. The Captiva EMR-Lipid solid-phase extraction (SPE) column is a new type of product that allows for selective and efficient lipid/matrix removal without negatively affecting the recovery of the analyte. In this study, samples were extracted with acidified acetonitrile and then purified using a Captiva EMR-Lipid SPE column. The target analytes were separated on a BEH C18 column by gradient elution using acetonitrile and water containing 0.1% (v/v) formic acid as the mobile phases. MS detection was performed with an electrospray source in the positive and negative modes in the multireaction monitoring (MRM) mode. The ion spray voltages were set at 5500 V and -4500 V in the positive and negative modes, respectively. The source temperature for both the ionization modes was set to 500 ℃. Instrumental parameters such as collision energy and declustering potential were optimized. The samples were quantified using the external standard method with matrix calibration curves to reduce the influence of the matrix effect on the quantitative results.
The results showed that the 50 veterinary drug residues had good linear relationships in the range of 0.5 to 50 μg/L, with correlation coefficients higher than 0.995. The limits of detection (LODs) and quantification (LOQs) were in the range of 0.03-0.70 μg/kg and 0.09-2.33 μg/kg, respectively. The average recoveries for all the compounds under different matrices ranged from 64.37% to 119.3% at spiked levels of 5 μg/kg and 50 μg/kg, with relative standard deviations of less than 15%. Compared to QuEChERS, this method has a better purification effect. The recoveries of the 50 veterinary drugs extracted by this method were also much higher than those in the case of QuEChERS. This method was applied to the detection of 14 domestic and six imported infant supplementary foods. Sulfaquinoxaline, sulfamethazine, and tilmicosin were detected in one imported meat-based baby food. With its simple operation, high sensitivity and accuracy, and low sample quantity consumption, this method is suitable for the determination of multiveterinary drug residues in complementary foods for infants and young children. This study provides an effective analysis method for risk monitoring and troubleshooting of complementary foods for infants and young children, which is of great significance in ensuring the healthy growth of the next generation.