超高效液相色谱-四极杆-飞行时间质谱检测和鉴定猪尿中氯丙那林的主要代谢产物

采用超高效液相色谱-四极杆-飞行时间质谱(UPLC/Q-TOF MS)检测和鉴定了猪尿中氯丙那林的主要代谢产物,并讨论了氯丙那林在猪体内的主要代谢途径。按10 mg/kg(b. w.)的剂量口服灌食氯丙那林,分别采集给药前及给药后的猪尿液样品。采用UPLC/Q-TOF MS对样品进行分析,并应用质量亏损过滤和离子色谱峰提取等数据处理技术,在给药后24 h内的猪尿中检测和鉴定了9种氯丙那林的代谢产物,其中,Ⅰ相代谢产物2种,Ⅱ相代谢产物7种。然后,根据氯丙那林原形和代谢产物的碎片离子特征,对代谢产物的结构进行鉴定。最后,根据所鉴定的代谢产物,推测氯丙那林在猪体内的代谢途径包括苯环羟基化、β -羟基和仲氨基的葡萄糖醛酸轭合、羟基化后的葡萄糖醛酸和硫酸轭合等。研究结果表明,羟基化氯丙那林及其轭合产物的相对含量大于60%,明显高于氯丙那林原形及其轭合产物,是尿液中的主要代谢产物。本研究将为确定氯丙那林在动物体内的残留标示物及加强对氯丙那林非法使用的监控提供科学依据。

Detection and identification of major metabolites of clorprenaline in swine urine using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry

This study was conducted to detect and identify the metabolites of clorprenaline in swine urine using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS), and the major metabolic pathways of clorprenaline were proposed. The swines were administered a single dose each of 10 mg/kg b. w. clorprenaline by oral gavage. The urine samples were collected before and after administration. After a simple preparation, the urine samples were analyzed using UPLC/Q-TOF MS. Combined with data processing techniques including extracted ion chromatography (EIC) and mass defect filtering (MDF), two phase Ⅰ and seven phase Ⅱ metabolites were detected in the urine samples collected 0-24 h after administration. The structures of detected metabolites were elucidated by comparing their characteristic product ions with those of the parent clorprenaline. Based on the identified metabolites, the metabolic pathways of clorprenaline included hydroxylation, glucuronidation and sulphate conjugates. Among those detected metabolites, hydroxylated-clorprenaline and its conjugates were responsible for over 60% of the total MS responses, much greater than those of clorprenaline, and were proposed as the primary metabolites in swine urine. This study can provide scientific basis for determining appropriate marker residues of clorprenaline, and facilitate to effectively control clorprenaline residues in animals.