Determination of olaquindox,carbadox and cyadox in animal feeds by ultra-performance liquid chromatography tandem mass spectrometry

Olaquindox, carbadox, and cyadox are chemically synthesised antibacterial and growth-promoting agents for animals. At high doses they may exert mutagenicity and hepatic and adrenal toxicities in animals. Regrettably, these substances are frequently abused or misused when added into animal feeds. Thus, developing a sensitive and reliable method for simultaneous determination of olaquindox, carbadox, and cyadox in different kinds of animal feeds is crucially important for food safety monitoring. In this paper we optimised instrumental conditions, extraction solvents, solid phase extraction cartridges, and pH of the loading solvents on the Oasis HLB cartridge. Under the optimal conditions, mean recoveries ranged from 74.1 to 111%, and intra-day and inter-day variations were lower than 14.6% and 10.8%, respectively. The limits of quantification for olaquindox, carbadox, and cyadox were 0.05 mg kg^?1, 0.10 mg kg^?1, and 0.025 mg kg^?1, respectively. The proposed method uses ultra-performance liquid chromatography tandem mass spectrometry and is sensitive and reliable for the simultaneous determination of olaquindox, carbadox, and cyadox in three kinds of animal feeds (specifically, mixed feed, concentrated feed, and additive premixed feed). This method has good precision, high sensitivity, and good reproducibility, and thus it can be used for convenient and accurate determination of olaquindox, carbadox, and cyadox in different kinds of animal feeds.     

3-甲基-喹噁啉-2-羧酸的合成

以喹乙醇为原料,经酸性还原,碱性水解、中和后得到3-甲基-喹噁啉-2-羧酸,探讨了反应条件对产率的影响。结果表明,喹乙醇在铁粉的酸性水溶液中活化后,85~90℃还原1 h,有机溶剂萃取得到N-羟乙基-3-甲基-2-喹噁啉酰胺,而后在12%氢氧化钠溶液中80~90℃水解6 h,盐酸酸化,得到纯度大于98%的3-甲基-喹噁啉-2-羧酸,总收率为60.6%。     

高效液相色谱-串联质谱法测定水产品中喹乙醇残留量

目的 建立高效液相色谱-串联质谱联用法测定水产品中喹乙醇残留量的方法。方法 以罗非鱼为实验样品, 样品经乙腈提取、正己烷脱脂, 以乙腈-0.5 mmol乙酸铵甲酸溶液(10:90, V:V)为流动相进行等度洗脱、色谱柱Poroshell 120 EC-C18(50 mm×2.1 mm, 2.7 μm)分离, 在多反应监测(multiple reaction monitoring, MRM)模式下进行三重四极杆质谱检测。结果 喹乙醇在0.02~0.4 mg/kg范围内线性关系良好, 检出限为0.4 μg/kg, 加标回收率(n=6)为93.8%~97.0%, 相对标准偏差为2.10%~8.02%。结论 该方法简单、快速、灵敏度高、准确可靠, 可用于批量水产品样品喹乙醇残留量的测定。     

Development of an on-line molecularly imprinted chemiluminescence sensor for determination of trace olaquindox in chick feeds

BACKGROUND: Olaquindox, as one of the antimicrobial growth accelerants, is usually used in livestock production to improve feed efficiency. Due to health concerns over possible carcinogenic, mutagenic and photoallergenic effects of olaquindox on animals, the development of simple, rapid and sensitive analytical method for determination of olaquindox is crucial and necessary. RESULTS: In this study, a surface molecularly imprinted polymer was prepared by a molecular imprinting technique in combination with a sol‐gel process using activated silica gel as a support material. This imprinted material exhibited with good recognition and selective ability, and fast adsorption‐desorption dynamics toward olaquindox. Using it as the recognition element, a new on‐line molecularly imprinted solid phase extraction coupled with chemiluminescence sensor for the determination of olaquindox was developed. The factors affecting preconcentration of the analytes and sensitivity of the method were all investigated. Under the optimal condition, the linear range of the calibration graph was between 2 × 10^?8 and 1 × 10^?6 g mL^?1, and the detection limit of this method was 7 × 10^?9 g mL^?1. The blank chick feed samples spiked with olaquindox at 0.3, 0.9 and 1.5 µg g^?1 levels were extracted and determined by this presented method with recoveries ranging from 87% to 94%. This method was validated by high‐performance liquid chromatography and the results correlated well with those obtained by both methods. Moreover, this method was quantitatively analysed with two contaminated chick feed samples. CONCLUSION: This study will provide a sensitive and fast method for the monitoring of olaquindox residues in foods. Copyright © 2012 Society of Chemical Industry     

喹乙醇火灾危险性研究

在喹乙醇火灾的调查中,由于缺乏对该物质的基本认知,火灾调查员在进行起火原因认定时存在困难.借助类比实验研究,确定不同引火源对喹乙醇引燃能力的大小,通过影像分析研究引燃过程中喹乙醇的燃烧现象及燃烧残留物的宏观特征,借助锥形量热法分析喹乙醇的燃烧特性,通过热分析技术研究喹乙醇的理化性质.结果表明:喹乙醇作为可燃粉末,能被常...     

Validation of an analytical method for the determination of carbadox and olaquindox in feedstuff by liquid chromatography coupled to UV and/or diode array detection

The performance characteristics of an analytical method based on high-performance liquid chromatography (HPLC) for the detection of the banned growth promoters, carbadox and olaquindox, in feedstuff were determined via a collaborative study. The relative standard deviation of repeatability (RSD_r) ranged 1.1-5.5% for carbadox and 2.5-6.2% for olaquindox. The relative standard deviation of reproducibility (RSD_R) ranged 6.4-10.7% for carbadox and 12.8-20.0% for olaquindox. In all cases, the HORRAT values were equal or below the critical value of 1.5. Moreover, trueness in all cases was between the acceptance limits of 80 and 110%. Consequently, it was concluded that the method is suitable for quantitative evaluation. The method was also qualitatively assessed in terms of correct identification of the target analytes by examination of the UV spectrum when the more specific diode array detector was coupled to HPLC. In all cases, the percentage of correct identifications was ≥94% for olaquindox and carbadox, while the percentage of false negatives was ≤6%, suggesting the extended utilization of the HPLC method from quantitative to confirmatory status with a diode array detector.     

2017~2019年昆明市市售食用鱼中几种违禁药物分析

目的 了解2017~2019年昆明市市售食用鱼中违禁药物残留状况。方法 2017~2019年随机采集市售食用鱼142份, 按照《国家食品污染和有害因素风险监测工作手册》检测违禁药物残留, 几种违禁药物都不得检出。结果 142件样品中违禁药物添加检出62件, 检出率39.4%(56件)。孔雀石绿和隐形孔雀石绿, 硝基呋喃代谢物, 喹乙醇及其代谢物检出率分别为2.8%(4件), 28.2%(40件), 8.4%(12件), 检出率最高的是硝基呋喃代谢物。违禁药物检出率最高的是鳝鱼, 其次是泥鳅。结论 昆明市市售食用鱼存在不同程度的违禁药物使用情况, 建议相关部门加大监管力度。     

超高效液相色谱-串联质谱法检测罗非鱼中喹乙醇及其衍生物

目的建立超高液相色谱-串联质谱法(ultra high pressure liquid chromatography-mass spectrometry,UPLC-MS/MS)测定罗非鱼中喹乙醇(olaquindox,OLQ)及其代谢物3-甲基-喹噁啉-2-羧酸(3-methyl-quinoxaline-2-carboxylic acid,MQCA)含量的分析方法。方法样品经10mL 50%甲醇溶液50℃水浴超声提取,PPL固相萃取小柱净化,经2 mL去离子水淋洗、2 mL 60%甲醇溶液洗脱,以乙腈-0.1%甲酸为流动相,经syncronis C_(18)色谱柱分离,采用多反应监测正离子模式进行定性及定量分析。结果 OLQ和MQCA在0.01～5.(μg/mL范围内线性关系良好,相关系数(r~2)均大于0.998,检出限为0.003 mg/kg和0.001 mg/kg,定量限为0.01 mg/kg和0.003 mg/kg,OLQ的3个水平加标回收率为87.0%～98.0%,RSD为3.3%～4.7%;MQCA的3个水平加标回收率为79.0%～84.0%,RSD为1.4%～3.6%。结论该方法具有灵敏度高、重复性好、准确度高、样品前处理操作简便和检测速度快的优点,适用于罗非鱼中喹乙醇及其代谢物MQCA快速高效定量、定性分析。     

改性壳聚糖为载体制备喹乙醇分子印迹聚合物及其表征

以交联化壳聚糖微球为表面载体,水和乙腈为混合溶剂,将模板分子（喹乙醇）,功能单体（丙烯酰胺）及交联剂（N,N’-亚甲基双丙烯酰胺）采用表面分子印迹与溶胶-凝胶法合成喹乙醇分子印迹聚合物（MIP）。并对新型水相分子印迹聚合进行红外光谱、扫描电镜、吸附动力学实验、吸附平衡实验、选择性实验的表征。实验结果表明:以壳聚糖为载体的分子印迹聚合物对喹乙醇的吸附容量为10.14mg·g-1,对喹烯酮的印迹效率因子为2.29,乙酰甲喹的印迹效率因子为2.22。以壳聚糖为载体的分子印迹聚合物具有较高识别选择能力,对喹乙醇具有快速吸附效果。      

In vivo studies to highlight possible illegal treatments of rabbits with carbadox and olaquindox

For the treatment of rabbit dysentery and bacterial enteritis, veterinary practitioners often adopt veterinary medicinal products authorised for other food-producing species, but in some cases non-authorised drugs frequently used in the past, such as carbadox and olaquindox, might be illegally adopted. To verify the carbadox and olaquindox distribution and persistence in rabbit tissues, two independent in vivo studies were carried out. In the first study, 24 healthy rabbits received water medicated with carbadox at 100 mg l^?1 over a period 28 days, whereas in the second one, 24 healthy rabbits were administered water containing olaquindox at 100 mg l^?1. In each study rabbits were randomly assigned to four groups to be sacrificed respectively at 0, 5, 10 and 20 days from treatment withdrawal, for depletion studies. A control group of six animals was adopted for control and as a reservoir of blank tissues. Muscle and liver samples collected from each treated animal were stored at ?20°C pending the analysis. Sensitive and robust liquid chromatography-tandem mass spectrometry analytical methods were set up for the parent compounds and their main metabolites quinoxaline-2-carboxylic acid, desoxycarbadox and 3-methylquinoxaline-2-carboxylic acid to verify their residual. Data collected demonstrate that the combination of liver as target matrix, quinoxaline-2-carboxylic acid and 3-methylquinoxaline-2-carboxylic acid as marker residue and enzymatic digestion is strategic to evidence carbadox and/or olaquindox illegal treatments in rabbits, even 20 days after treatment withdrawal at concentration levels higher than 0.5 µg kg^?1. This findings suggests that liver should be proposed as target matrix for official control in national monitoring plan.