氟苯尼考在产蛋前期鸡蛋中的残留规律及膳食暴露评估

目的：为了探索开产前蛋鸡使用氟苯尼考后产蛋前期鸡蛋中氟苯尼考的残留规律,评估氟苯尼考对鸡蛋安全性的影响,评价其食用风险。方法：蛋鸡开产前不同时间预防性投喂氟苯尼考后测定鸡蛋中氟苯尼考残留量。结果：给药期间鸡蛋中氟苯尼考和氟苯尼考胺的残留量逐渐升高可达到峰值,或停药后1 d达到峰值,最大残留量出现在第4组为515.86 μg/kg。停药后5 d,鸡蛋中氟苯尼考和氟苯尼考胺的残留总量基本小于100 μg/kg。随着蛋鸡日龄的增长,产蛋率逐渐升高,停药后10~14 d鸡蛋中氟苯尼考和氟苯尼考胺残留量低于检出限。结论：对照实验各组鸡蛋中的检出是氟苯尼考和氟苯尼考胺的浓度总和,开产前23 d使用氟苯尼考,开产后所产鸡蛋对成人和婴儿都是安全的。     

恩诺沙星、氟苯尼考和泰万菌素在鸡蛋中残留消除规律研究

目的 评估恩诺沙星、氟苯尼考和泰万菌素在鸡蛋中的残留消除规律。方法 将80羽高产海兰褐蛋鸡随机等分成4组, 对照组饲喂基础日粮, 恩诺沙星组、氟苯尼考组和泰万菌素组分别经混饲给予相应药物, 每日1次, 连续给药5 d, 停药19 d, 检测各枚鸡蛋中相应药物及其主要代谢产物的残留量。结果 恩诺沙星及其主要代谢产物环丙沙星与氟苯尼考及其主要代谢产物氟苯尼考胺可迅速残留于鸡蛋中, 残留物分别以恩诺沙星原型和氟苯尼考原型为主, 且其残留蓄积期都超过19 d。泰万菌素及其主要代谢产物3-乙酰胺基泰万菌素在鸡蛋中的残留总量低于最大允许残留限量, 且平均残留蓄积期为7 d, 3-乙酰胺基泰万菌素占总残留量的50%以上。结论 恩诺沙星和氟苯尼考在海兰褐品系鸡蛋中残留消除周期超过19 d, 在对后备蛋鸡、肉蛋兼用鸡给药时需严格控制用法用量。在适用情况下, 可优先选择平均残留消除周期相对较短的泰万菌素。     

氟苯尼考在鸡蛋和蛋鸡组织中的残留规律及预测模型建立

氟苯尼考是一种被广泛应用于动物养殖过程中的抗生素药物，可能残留于畜产品中，被人类长期食用会对机体造成耐药性、免疫抑制等不良影响。本实验旨在探讨蛋鸡摄入不同剂量氟苯尼考后，鸡蛋及各组织中氟苯尼考及其代谢产物氟苯尼考胺的清除规律，建立残留预测数学模型。本实验选取处于产蛋高峰期的罗曼粉壳蛋鸡250 只（350 日龄、体质量（1.97±0.07）kg），随机分为5 组，每组50 只，分别给予氟苯尼考0（对照）、30、60、120、240 mg/（kg mb·d），连续给药5 d。采用液相色谱-串联质谱法测定不同休药时间点蛋黄、蛋清、卵黄、肌肉、肝脏中氟苯尼考及其代谢产物氟苯尼考胺的残留含量。结果表明：休药1～3 d时，240 mg/（kg mb·d）剂量组蛋鸡产蛋率与其他处理组相比显著降低（P＜0.05），休药4 d后恢复至对照组水平；氟苯尼考及其代谢产物氟苯尼考胺在产蛋鸡组织中残留含量分布：蛋黄＞卵黄＞蛋清＞肝脏＞肌肉；不同组织残留氟苯尼考及氟苯尼消除所需休药时间：肝脏＜肌肉＜蛋清＜蛋黄＜卵黄；氟苯尼考给药剂量和休药时间对残留含量影响高度显著（P＜0.001），且给药剂量与休药时间互作效应高度显著（P＜0.001）。休药时间、给药剂量和残留含量之间呈现二元二次回归关系（P＜0.001）。为达到《中国兽药典（2015年版）》所规定的氟苯尼考给药剂量范围（40～60 mg/（kg mb·d）），肌肉等组织需休药1 d、蛋清蛋黄需休药13 d、卵黄需休药21 d。     

恩诺沙星注射液在猪体内残留消除规律研究

目的研究恩诺沙星注射液在猪体内的残留消除规律。方法本实验采用30头约50 kg重长白猪,随机分为2组,给药组25头,对照组5头。给药组用药量为每次2.5mg恩诺沙星/kg,每日1次,连用3d(1个疗程),使用1个疗程,对照组不给任何抗菌药物,与给药组同环境饲养。在最后一次给药6 h、24 h(1 d)、72 h(3 d)、120 h(5 d)、168 h(7 d)时采集肉、肝、肾、脂肪样本,经液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry, LC-MS/MS)测定组织中的恩诺沙星及其代谢物环丙沙星残留量之和,并利用WT1.4软件计算休药期。结果恩诺沙星注射液在猪肉中的休药期为3.17 d;在肾脏中的休药期为3.75 d;在肝脏中的休药期为8.18 d;在脂肪总的休药期为4.09 d。结论为保证兽药使用安全、食品安全和消费者健康,推荐恩诺沙星注射液在猪体内的休药期为9 d。     

恩诺沙星在余干乌鸡不同组织中的残留消除规律研究

目的 研究恩诺沙星可溶性粉在余干乌鸡各组织内的残留消除规律.方法 88只110 d龄健康余干乌鸡,随机分为11组,以0.75 g/L饮水连续给药5 d.停药后第0.16、1、3、5、7、9、20、30、40 d采集肌肉、肝脏、肾脏、皮脂样本,经液相色谱-串联质谱法测定组织中恩诺沙星和环丙沙星残留量,计算药物代谢半衰期,...     

禽蛋中氟苯尼考代谢物快速检测方法的建立

基于免疫层析技术建立禽蛋中氟苯尼考残留标志物（氟苯尼考与氟苯尼考胺之和）的快速检测方法。采用乙酸乙酯对禽蛋中氟苯尼考及其主要代谢物氟苯尼考胺进行提取,并用二氯乙酸酐将提取液中的氟苯尼考胺衍生化为氟苯尼考,最后用氟苯尼考胶体金检测卡进行检测。结果表明,氟苯尼考胺在乙酸乙酯体系中成功衍生化为氟苯尼考,氟苯尼考及氟苯尼考胺检出限分别为1、3 μg/kg。另外,通过对实际阳性鸡蛋样品及加标样品进行检测,其结果与国标方法测量结果基本一致。本方法具有简便、快速、低成本等特点,适合大批量样品的现场筛查,提高监管效率。     

地西泮在鲫鱼不同组织中的残留消除规律研究

目的 掌握地西泮在鲫鱼不同组织中的残留消除规律,合理确定休药期。方法 以鲫鱼为研究对象,用地西泮(初始质量浓度为1.0μg/L)进行药浴,水温控制在(20.0±1.0)℃,分别于给药后的0.5、1、2、3、4、6、8、10、12、24、48、72、96、144、240、288、360、480、600、840、1080、1320 h对鲫鱼肌肉+皮、鳃、肝脏、肾脏、脑、心脏以及血浆等进行检测,探讨鲫鱼不同组织中地西泮药物残留消除规律,并利用WT1.4软件计算地西泮在鲫鱼体内的休药期。结果 地西泮在水产品中的代谢周期较长。肌肉组织的休药期为74 d,鳃的休药期为121 d,肝脏的休药期为174 d,肾脏的休药期为100 d,脑的休药期为78 d,心脏的休药期为45 d,血浆的休药期为106 d.结论 为保证鲫鱼质量安全和消费者健康,建议在养殖温度为20℃时,对鲫鱼单剂量(1.0μg/L)药浴地西泮后的休药期为174 d。     

液相色谱-串联质谱法检测蜂蜜中氟苯尼考及其代谢物残留量

目的 建立液相色谱-串联质谱法检测蜂蜜中氟苯尼考及其代谢物残留量的分析方法。方法 样品经氨化乙酸乙酯提取,通过DPC-2固相萃取柱净化,采用Poroshell 120 EC-C18柱分离,以10 mmol/L乙酸铵溶液-乙腈为流动相进行梯度洗脱,电喷雾正/负离子切换,多反应监测模式检测,同位素内标法定量。结果 氟苯尼考在0.2～30 μg/L时具有良好的线性关系,相关系数大于0.999,检出限为0.05 μg/kg,回收率为85.5%~116.3%,相对标准偏差小于10%。氟苯尼考胺在1～30 μg/L时具有良好的线性关系,相关系数大于0.999,检出限为0.3 μg/kg,回收率为85.6%~113.5%,相对标准偏差小于10%。结论 该方法快速、准确、灵敏, 适用于蜂蜜中氟苯尼考及其代谢物残留量的测定。     

气相色谱质谱法检测鸡蛋中氟苯尼考及氟苯尼考胺

建立了气相色谱飞行时间质谱法同时检测鸡蛋中氟苯尼考和氟苯尼考胺的残留。样品经氨化乙酸乙酯提取,采用气相色谱飞行时间质谱法测定。试验结果表明:在2~100 ng/mL的范围内,线性良好,氟苯尼考R²=0.999,氟苯尼考胺R²=0.998;该方法两种物质的检出限为0.5μg/kg;在0.5、1.5、10.0μg/kg的3个水平,氟苯尼考及氟苯尼考胺的回收率在86.4%~119.4%,相对标准偏差RSD(n=3)为2.9%~7.1%,该方法简单、快速、高效,可用于鸡蛋中氟苯尼考及氟苯尼考胺的同时测定。     

超高效液相色谱-串联质谱法测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留

目的建立超高效液相色谱-串联质谱准确测定鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留的分析方法。方法鸡肉和鸡蛋样品加入D5-氯霉素内标,经氨化乙酸乙酯混合溶液超声离心提取,提取液减压蒸馏浓缩后,C18固相萃取柱净化处理,采用超高效液相色谱-串联质谱法对氟苯尼考和氟苯尼考胺同时进行检测。结果氟苯尼考线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为88.0%～108.0%,相对标准偏差为4.7%～6.4%;氟苯尼考胺线性范围为0.2～20μg/L,检出限为1.0μg/kg,定量限为3.0μg/kg,方法回收率为76.0%～93.1%,相对标准偏差为4.1%～7.2%。结论本方法精确、重现性好,适用于鸡肉、鸡蛋中氟苯尼考和氟苯尼考胺残留量的测定。     

A reliable,simple and cost-efficient TLC-HPLC method for simultaneously determining florfenicol and florfenicol amine in porcine urine: application to residue surveillance

ABSTRACT

Violative residues of florfenicol (FF) in porcine edible tissues pose a potential risk for human health. In this study, urine was selected as target matrix for routine residue monitoring of FF in pig, and a thin layer chromatography (TLC)-high-performance liquid chromatography (HPLC) method was developed for simultaneously determining FF and florfenicol amine (FFA) in porcine urine. The urine samples were extracted with ethyl acetate under alkaline environment. The extracts were enriched through evaporation, purified by TLC and analysed by HPLC at 225 nm. A Waters Symmetry C₁₈ column was used for the separation of the two analytes. The mobile phase was acetonitrile-phosphate buffer mixtures (33.3: 66.7, v/v), and was pumped at 0.6 mL/min. The TLC-HPLC method was well validated and successfully applied to residue depletion study. Good analytical specificity was confirmed by the lack of interfering peaks at the retention times of FF and FFA. The standard curves showed good linearity (FF: y = 143064x – 1045.3, r= 0.9999; FFA: y = 275826x + 1888.8, r= 0.9999) over the range of 0.0625–8 μg/mL. The precision ranged from 0.83% to 11.66% and 2.19% to 8.75% for intraday and interday determination, respectively. The corresponding accuracy ranged from ?13.38% to 10.78% and ?12.15% to 7.14%, respectively. The limits of quantification (LOQs) for FF and FFA were 0.125 μg/mL. The residue depletion study showed that the concentrations of FF and FFA in urine were higher than those in edible tissues at three time points. This method was reliable, simple and cost efficient, and could be used to monitor FF residues in porcine edible tissue without slaughtering animals. TLC showed excellent purification efficiency and is expected to solve matrix interferences in veterinary drug residue analysis.     

池塘养殖模式下氟苯尼考及其代谢产物在斑点叉尾鮰体内的药代动力学

目的在实际大池塘养殖模式下,研究氟苯尼考(florfenicol,FF)及其代谢产物在斑点叉尾鮰(Letaurus以下简称鮰)体内药代动力学。方法选择4口标准化池塘(2300 m~2/口),养殖密度按每666.67 m~2投放鱼苗1000尾投放,设3个实验组和1个对照组。实验组分别以1.25、2.50、5.00 g/kg 3个剂量水平在鮰饲料中添加FF,每天投喂饲料4 kg(一次投入),对照组投喂不含FF的等量饲料。连续投喂5 d后,分别于首次投药后的第1、2、3、4、5、6、7、8、11、14、30、60、90和170 d采集鮰肌肉、肝脏及血液,采用高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)检测FF及氟苯尼考胺(florfenicol amine,FFA)含量,采用PKSolver药动学药效学数据处理软件V2.0的药动学房室模型拟合方法分析药时数据。结果 FF在鮰血液中的药代动力学特征符合一级吸收一室模型,而在肝脏及肌肉中均符合一级吸收二室模型,FFA在不同组织中均符合一级吸收二室模型。结论 FF在鮰体内主要以原型的方式代谢消除,分布广泛且FF消除速率远高于FFA,肝脏可作为残留分析的靶组织。     

基于纳米金比色法可视化检测鸡蛋中的氟苯尼考

该研究基于适配体功能化的纳米金构建了比色传感器,在优化各种试验条件的基础上,评估了传感器的灵敏性及特异性,并对鸡蛋中氟苯尼考检测的可行性进行了研究,进而探索将比色传感器与智能手机的成像分析相结合实现快速分析的可行性.比色传感器的优化条件如下:NaCl浓度为50 nmol/L,NaCl孵育时间为5 min,适配体浓度为7...     

Depletion of florfenicol and florfenicol amine in eggs of laying hens and growing pullets after oral administration

ABSTRACT

In this study, we carried out two experiments to evaluate depletion of florfenicol (FF) and its metabolite florfenicol amine (FFA) in eggs from growing pullets and laying hens. Eggs were collected, and the egg white and yolk were separated. FF and FFA were analysed by liquid chromatography-tandem mass spectrometry. In the first experiment, 30 laying hens were given FF capsules at 50 mg/kg·bw^?1 daily for 5 d. FF + FFA was detectable in egg white (1,190 µg/kg) on day 1 of treatment and increased slowly thereafter. After treatment, the residues decreased rapidly and were not detected by day 11. In yolk, residues were detected at a lower concentration on day 1 and increased dramatically to 3308 µg/kg at the end of treatment. The residues remained steady over the next 4 days post-treatment, followed by a rapid drop. Residues were not detectable on day 15 post-treatment. In the second experiment, four groups (B1 through B4) of growing pullets were treated in the same manner for 25, 20, 15, and 10 days before egg primiparity. FF and FFA were not detectable in the eggs of group B1; however, they were detectable in egg whites and yolks of groups B2, B3, and B4. The highest total concentrations of FF and FFA detected in egg white and yolk of group B4 were 3,190 µg/kg and 3,214 µg/kg, respectively. Thereafter, concentrations decreased until no more residues were detected in egg whites or yolks on days 17 and 21 post-treatment, respectively. Therefore, drug treatment should be stopped at least 21 d before primiparity of growing pullets to guarantee food safety.     

Simultaneous determination of chloramphenicol,florfenicol and florfenicol amine in ham sausage with a hybrid chemiluminescent immunoassay

A novel chemiluminescent immunoassay utilising two types of primary antibodies (murine monoclonal antibody and rabbit polyclonal antibody) and two types of horseradish peroxidase–labelled secondary antibodies was established for simultaneously detecting multiple amphenicol residues in ham sausage. After combining the extract procedure of the target amphenicol into one simplified method, this hybrid chemiluminescent immunoassay could screen chloramphenicol (CAP), florfenicol (FF) and its metabolite florfenicol amine (FFA) at the same time by adding the corresponding secondary antibody. Ham sausage samples were analysed by using this hybrid immunoassay, with LODs of CAP being 0.01 μg kg^?1, of FF being 2.8 μg kg^?1 and of FFA being 3.0 μg kg^?1. The applicability of the proposed method has been validated by determining CAP, FF and FFA in ham sausage samples with satisfactory results. Good recoveries and high correlation with traditional enzyme-linked immunosorbent assay and LC-MS/MS results illustrated that the developed hybrid chemiluminescent immunoassay could screen high-throughput ultra-trace amphenicol residues effectively at one time.     

Evidence of non-extractable florfenicol residues: development and validation of a confirmatory method for total florfenicol content in kidney by UPLC-MS/MS

The parent compound florfenicol (FF) is a broad-spectrum antibacterial compound licensed in the UK for use in cattle, pigs and the aquaculture industry. The analysis of porcine tissues in this study demonstrates that significant amounts of solvent non-extractable FF-related residues are present in incurred tissues (kidney and muscle) from treated animals. The results indicate that methods based on solvent extraction alone may carry a significant risk of reporting false-negative results. The use of a strong acid hydrolysis step prior to solvent extraction of tissue samples is necessary for an accurate estimate of the total tissue FF content. A robust and sensitive method for the determination of total FF residue content in kidney samples by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been developed and validated. This method covers the synthetic amphenicol drug FF and its metabolites, measured as the marker residue florfenicol amine (FFA) as per Commission Regulation (EU) No. 37/2010. Non-extractable and intermediate metabolites are converted to the hydrolysis product FFA, and then partitioned into ethyl acetate. Extracts are solvent exchanged prior to a dispersive solid-phase extraction step, then analysed using an alkaline reverse-phase gradient separation by UPLC-MS/MS. The method was validated around the maximum residue levels (MRLs) set out in Regulation (EU) No. 37/2010 for bovine kidney in accordance with Commission Decision No. 2002/657/EC. The following method performance characteristics were assessed during a single laboratory validation study: selectivity, specificity, sensitivity, linearity, matrix effects, accuracy and precision (decision limit (CCα) and detection capability (CCβ) were determined).     

LC-MS/MS-based determination of chloramphenicol,thiamphenicol, florfenicol and florfenicol amine in poultry meat from the Punjab-Pakistan

A simple, reliable and sensitive liquid chromatography-tandem mass spectrometry-based confirmatory method was redeveloped and validated for the simultaneous determination of chloramphenicol, thiamphenicol, florfenicol and florfenicol amine in chicken muscles. The analytes were extracted from minced chicken muscle with acetonitrile and ammoniated water mixture. A second extraction with ethyl acetate was followed by evaporation and dissolution of the residue in ammoniated methanol before defatting with n-hexane. Finally, the extract was further cleaned up by dispersive solid phase extraction using C-18 end-capped dispersive material. The validation protocol was adapted from the European Commission Decision 2002/657/EC and all the performance characteristics were successfully satisfied. The recoveries of all the analytes were found to be in the range of 86.4–108.1% and the precision values, within day and between days, ranged from 2.7% to 11% and 4.4% to 16.3%, respectively. The method was tested in various incurred samples and applied to analyse a wide range of random poultry market samples (n = 120) collected from three cities of the Punjab, Pakistan. Chloramphenicol and florfenicol residues were detected at low levels in less than 11% of the samples. Chloramphenicol was detected only in 4 samples with the concentration range of 0.17–0.477 µg kg^–1, whereas the levels of florfenicol/florfenicol amine residues detected in 9 samples ranged from 8.7 to 32.8 µg kg^–1. Moreover, most of the florfenicol residues were identified as tissue bound, extractable only after strong acid hydrolysis.     

UPLC-MS/MS法测定禽蛋中氟苯尼考及氟苯尼考胺

建立一种超高效液相色谱-串联质谱法同时测定禽蛋中氟苯尼考(FF)和氟苯尼考胺(FFA)含量的方法。样品经2%氨水-乙酸乙酯提取,PRiME HLB固相萃取(SPE)柱净化。采用Hypersil GOLD C18色谱柱(100 mm×2.1mm,1.9μm),以乙腈(B1)-0.1%甲酸水(A2)为流动相进行梯度洗脱。氟苯尼考和氘代氟苯尼考采用电喷雾负离子源,氟苯尼考胺采用电喷雾正离子源,多反应监测模式,以氘代氟苯尼考(氟苯尼考-d3)为氟苯尼考进行内标定量,氟苯尼考胺外标法定量。结果表明,氟苯尼考和氟苯尼考胺在0.2~10μg/L范围内均呈良好线性关系(r≥0.9978)。加标浓度分别为0.1,0.2和1μg/kg及0.5,1.0和5.0μg/kg,回收率分别在91.0%~100.9%和73.7%~84.3%之间,相对标准偏差均<3.52%(n=6)。氟苯尼考的检出限和定量限分别为0.05μg/kg和0.1μg/kg,氟苯尼考胺的检出限和定量限分别为0.25μg/kg和0.5μg/kg。该方法准确、灵敏、快速,能有效并同时检测禽蛋中氟苯尼考和氟苯尼考胺含量。