An improved microbial assay for the detection of chloramphenicol residues in shrimp tissues

An improved microbial assay was developed for the detection of chloramphenicol (CAP) residues in shrimp muscle using Photobacterium leiognathi (L-2 strain) isolated from squid, as test organism, using a pad plate technique. CAP spiked in shrimp muscle tissues at concentrations ranging from 1 to 100 μg/kg was extracted using ethyl acetate and ammonium hydroxide. The assay showed a maximum inhibition zone of 23.0 mm for 100 μg/kg and a minimum inhibition zone of 9.3 mm for 1 μg/kg. The method had a good recovery of 95.63% with a minimum detection limit of 1 μg/kg. It can be performed within 18 h following simple extraction. The method therefore proved to be advantageous over chromatographic procedures as it was inexpensive, quite sensitive and can be adopted for rapid screening of CAP in shrimp tissues.     

微生物显色法检测禽畜肉中混合抗生素残留

以微生物显色为原理,建立一种对畜禽肉中单一或配伍使用的抗生素进行联合初筛的高通量方法,并用色谱法对阳性样品进行验证。以大肠埃希氏菌（Escherichia coli,CICC 23657）作为指示菌,选取适当的抗生素残留提取方法,并通过单因素试验优化检测液配方及检测体系组成,最终实现对不同类别抗生素的联合检测。结果表明：选取柠檬酸-丙酮缓冲液进行提取,提取效率达到86%～88%,相对标准偏差为3.9%～4.3%;蛋白胨添加量为1.0 g/100 mL、溴甲酚紫指示剂添加量为2.0 mg/100 mL、pH值为7.2时,检测液显色效果较好;菌悬液初始吸光度（A600 nm）为0.4,检测液、菌液、样品提取液体积为150 μL∶50 μL∶100 μL时,检测效果最佳,对畜禽肉中喹诺酮类抗生素的检出限为60～180 μg/kg,氨基糖苷类检出限为60～140 μg/kg,喹诺酮类与氨基糖苷类配伍使用时的检出限为40～180 μg/kg;进一步用色谱法对50 份样品的初筛结果进行验证,无假阴性样品存在,说明该方法可用于畜禽肉中抗生素残留的初筛。     

超高效液相色谱-串联质谱法同时测定水产制品中22种全氟烷基物质

目的 建立超高效液相色谱-串联质谱法同时检测水产制品中22种全氟烷基物质(perfluorinated alkyl substances,PFASs)定性定量检测方法.方法 选取基质成分复杂的水产制品作为检测目标.样品经乙腈(含1％甲酸)提取液涡旋振荡提取,分散固相萃取结合通过式固相萃取柱进行净化,C18色谱柱分离,甲...     

豆芽中30种植物生长调节剂和喹诺酮类药物残留的快速筛查

基于通过型固相萃取净化方法,建立超高效液相色谱-串联质谱（HPLC-MS/MS）法快速筛查豆芽中30种植物生长调节剂和喹诺酮类药物残留的方法。样品以90%乙腈水（含0.1%甲酸）提取,PRiME HLB（新型反相固相萃取小柱）净化,采用Agilent SB-Aq RRHD 色谱柱（2.1 mm×100 mm,1.8 μm）进行分离,乙腈和0.1%甲酸水溶液为流动相梯度洗脱,采用电喷雾离子源（ESI）在正、负离子多反应监测（MRM）模式下检测,基质加标标准曲线外标法定量。结果显示:30种化合物在2～500 μg/L范围内线性良好（r>0.991）,方法检出限为0.04～1.67 μg/kg,定量限为0.1～5.6 μg/kg,平均回收率为74.0%～113.5%,相对标准偏差（RSD）为0.6%～7.7%（n=6）。该方法操作简便,灵敏度高,可对豆芽中30种植物生长调节剂和喹诺酮类药物进行快速筛查。     

Liquid Chromatography–Tandem Mass Spectrometry Multiclass Method for 46 Antibiotics Residues in Milk and Meat: Development and Validation

A screening method for analysis of 46 antibiotics residues, belonging to different classes, such as tetracyclines, sulfonamides, fluoroquinolones, β-lactams, cephalosporins, macrolides and other minority groups was developed and validated for application in bovine milk and bovine, swine, poultry, equine, fish and shrimp meat samples. Sample preparation consists in solvent extraction followed by clean up with C18 bulk and low temperature purification. Instrumental analysis was performed using liquid chromatography coupled to tandem mass spectrometry system. Chromatographic separation was achieved using a C18 column. Mobile phase was composed by methanol and water. The method was validated according to Commission Decision 2002/657/EC criteria. Validation parameters such as specificity and detection capability (CCβ) were determined and considered suitable to the established criteria. Values of CCβ ranged from 1.0 to 50.0 μg L^?1 or μg Kg^?1, depending on the compound and the matrix. The proposed method has been applied into Brazilian National Residue Control Plan since 2013 for the determination of antibiotic residues. A total of 3833 samples were analyzed until the current date and 13 samples showed positive results with concentrations above the permitted. The method is fast, easy and adequate for high throughput analysis in routine laboratories.     

分散固相萃取-GC-MS法测定海产品中9种有机锡化合物

本实验建立了一种同时检测海产品中9种有机锡化合物的新方法.样品依次经过超声波提取,冷冻脱脂,N-丙基乙二胺(PSA)分散固相萃取、四乙基硼酸钠衍生、石墨化炭黑(GCB)分散固相萃取,最后采用气相色谱-质谱法(GC-MS)进行测定.在优化条件下,9种有机锡化合物的线性范围为10～1000 pg/L,相关系数为0.9952...     

胶体金免疫层析法定量检测鱼和虾中苯巴比妥残留

建立了一种快速定量检测水产品鱼和虾中苯巴比妥残留的胶体金免疫层析方法。采用胶体金纳米粒标记苯巴比妥单克隆抗体,研究了胶体金免疫层析条件如标记体系p H值、标记抗体浓度、检测T线包被原浓度、质控C线羊抗鼠Ig G浓度、样品前处理方法等对胶体金灵敏度的影响,并借助胶体金试纸条读数仪进行定量检测。结果表明:方法检出限为0.07 ng/mL,线性范围0.08～0.94ng/m L,裸眼消线值(cut-off值)为10.0 ng/mL。方法特异性良好,与巴比妥、戊巴比妥、异戊巴比妥三种结构类似物交叉反应率小于10%。选择罗非鱼、草鱼、鲈鱼和虾进行添加回收试验,样品回收率在73.50%～114.17%之间,相对标准偏差小于15%,且结果与UPLC-MS/MS法一致。该方法具有准确、灵敏、简便、快速等特点,非常适用于水产品鱼和虾中苯巴比妥残留现场快速筛查。     

EMR固相萃取-超高效液相色谱-串联质谱法测定虾肉中性激素残留的方法建立

本研究建立EMR固相萃取结合超高效液相色谱-串联质谱测定虾肉中15种性激素残留的分析方法。样品采用0.1 mol/L乙二胺四乙酸二钠溶液-乙腈溶液提取,经Captiva EMR固相萃取SPE小柱净化,CAPCELLPAK C₁₈ BB-H（3 μm,2.1 mm×150 mm）色谱柱分离,电喷雾离子源正负离子分开扫描;多反应监测模式的超高效液相色谱-串联质联质谱法进行检测,以空白基质匹配外标法定量。正离子流动相为甲醇和0.1%甲酸,检测雄激素与孕激素;负离子流动相为乙腈和0.01%氨水溶液,检测雌激素。结果表明,经EMR固相萃取净化的虾肉样品中的15种性激素残留在1～50 μg/kg浓度范围内线性关系良好,相关系数（r）均大于0.99,方法检出限为0.0015～0.436 μg/kg,定量限为0.0051～1.453 μg/kg,平均回收率在85.31%~119.84%,相对标准偏差为2.11%~9.86%（n=6）。本方法操作快速简单,重复性好,灵敏度较高,适用于虾肉中15种性激素残留的检测。     

固相萃取结合高效液相色谱-串联质谱法测定鸡蛋中那西肽残留

建立鸡蛋样品中那西肽的高效液相色谱-串联质谱检测方法.样品经甲酸-乙腈溶液提取后,正己烷除脂,再经HLB固相萃取柱净化;样品溶液通过高效液相色谱-串联质谱进行检测,采用负离子模式电喷雾电离,配合多反应离子扫描分析目标化合物.分别对样品前处理条件及色谱质谱参数进行优化.结果表明,采用1％甲酸-乙腈溶液萃取,经HLB固相萃...     

Fast and simple determination of moroxydine residues in pig and chicken samples by ultra-performance liquid chromatography-tandem mass spectrometry

ABSTRACT

A general solid-phase extraction (SPE) method using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the determination of moroxydine residues in pig and chicken samples has been developed. After extraction and purification of real samples, moroxydine residues were detected using a hydrophobic interaction liquid chromatography column with an optimised mobile phase composition. The extraction reagents, the kind of SPE columns and the type of eluents were optimised to achieve the maximum extraction efficiency. The matrix effects from the animal tissue influenced the quality of the quantitative data obtained. Under the optimised conditions, the moroxydine residues in pig and chicken samples spiked at three levels (1.0 μg/kg, 5.0 μg/kg and 10.0 μg/kg) were determined with good recoveries (61.5%–105.4%) and adequate relative standard deviations (3.2%–13.0%). In pig and chicken samples, the limit of detection (LOD) was 0.3 μg/kg, and the limit of quantification (LOQ) was 1.0 μg/kg. A sufficiently linear relationship in the range of 1.0 μg/kg–20.0 μg/kg was achieved with a good correlation coefficient (R² ≥ 0.99).     

液相色谱-串联质谱结合谱库检索测定猪组织中13种氟喹诺酮类药物

采用MRM→IDA→EPI→谱库检索模式建立了猪组织中13种氟喹诺酮类药物的液相色谱-电喷雾串联质谱多残留检测方法,结合谱库检索功能同时实现了定性定量分析.组织样品经N,N-二甲基甲酰胺-乙腈混合溶液提取,Waters HLB柱净化,本方法13种氟喹诺酮类药物的线性范围为1.0～5000.0 μg/kg,线性相关系良好...     

胶体金免疫层析法和气相色谱法测定动物产品中氯霉素残留

对动物产品中氯霉素残留检测的胶体金免疫层析法和气相色谱法进行比较研究。向样品中分别添加0.3、0.5、1.5μg/kg三个添加水平的氯霉素标准品,用两种方法进行检测。胶体金免疫层析法对0.5μg/kg以上均能检出,气相色谱法平均回收率分别为78.1%、85.3%和88.3%,变异系数为5.3%～9.0%,最低检测限为0.3μg/kg。对108个样品用胶体金免疫层析法筛选出3个阳性样品,经气相色谱法验证皆为阳性,105个阴性样品经气相色谱法检测皆为阴性,未发现假阳性和假阴性。结果表明：胶体金免疫层析法具有快速,简便,特异,灵敏度高的特点,适合基层检验机构对动物产品中氯霉素残留现场快速筛选;气相色谱法灵敏度高,适用于阳性样品的精确定量。     

水产品中恩诺沙星残留的一步法酶联免疫检测研究

采用过碘酸钠氧化法合成了辣根过氧化物酶(HRP)标记的恩诺沙星抗体,建立一步式直接竞争酶联免疫吸附检测(ELISA)技术,并以鳗鱼为样本进行了恩诺沙星残留的加标检测。结果表明,所制备的酶标记抗体效价达到10000 以上,与同族其他药物及族外药物没有显著的交叉反应;所建立的一步式ELISA 法检测限约为10μg/kg。在10～40μg/kg 浓度范围内,加标鳗鱼样本中恩诺沙星的检测回收率在70% 以上,相对平均偏差小于6%,检测时间缩短到2h 以内,约为传统两步式ELISA 法的一半左右。     

酶标抗原直接竞争ELISA检测食品中氟喹诺酮类药物多残留

固相包被恩诺沙星抗体,辣根过氧化物酶标记的抗原与标准品（或样品）中氟喹诺酮药物竞争结合抗体,建立了高效、高灵敏的氟喹诺酮药物直接竞争酶联免疫吸附分析检测方法。优化反应条件后,得到方法的IC50为2.04 μg/L,灵敏度为0.15 μg/L,线性范围0.3～15 μg/L;方法可以检测12 种氟喹诺酮药物,在生乳、鸡肉、鱼肉和虾肉4 种样品中12 种药物的回收率为70%～121.5%。     

Development of a quantitative immuno-affinity test column assay for on-site screening of clindamycin residues in milk

A sensitive and specific monoclonal antibody against clindamycin (CLIN) was produced and used to develop an immuno-affinity test column (IATC) assay for on-site screening of CLIN residues in milk. The qualitative limit of detection of the IATC assay, estimated as 1.0 μg L⁻¹ by visual detection, was sufficient to measure maximum residue levels for lincosamide antibiotics in milk. The quantitative IATC assay resulted in a lower detection limit (0.11 μg L⁻¹) by evaluating the colour intensity of the test layers, which was approximately 9 times greater sensitivity than visual detection. During the spike and recovery test, the average recoveries ranged from 76% to 114% at different spiked levels, and the intra-/interday coefficients of variation were in the range 9.6–16.7%. The detection time was shortened to 20 min, whereas the sensitivity was comparable with a traditional ELISA. The IATC assay shows promise for on-site screening of CLIN residues in milk.     

Hog Charm II tetracycline test screening results compared with a liquid chromatography tandem mass spectrometry 10-μg/kg method

Pork tissue samples that tested positive and negative by the Charm II tetracycline test screening method in the slaughter plant laboratory were tested with the modified AOAC International liquid chromatography tandem mass spectrometry (LC-MS-MS) method 995.09 to determine the predictive value of the screening method at detecting total tetracyclines at 10 μg/kg of tissue, in compliance with Russian import regulations. There were 218 presumptive-positive tetracycline samples of 4,195 randomly tested hogs. Of these screening test positive samples, 83% (182) were positive, >10 μg/kg by LC-MS-MS; 12.8% (28) were false violative, greater than limit of detection (LOD) but <10 μg/kg; and 4.2% (8) were not detected at the LC-MS-MS LOD. The 36 false-violative and not-detected samples represent 1% of the total samples screened. Twenty-seven of 30 randomly selected tetracycline screening negative samples tested below the LC-MS-MS LOD, and 3 samples tested <3 μg/kg chlortetracycline. Results indicate that the Charm II tetracycline test is effective at predicting hogs containing >10 μg/kg total tetracyclines in compliance with Russian import regulations.     

免疫亲和柱净化-超高效液相色谱-串联质谱检测鱼虾中3-甲基-喹噁啉-2-羧酸

将特异性强的免疫亲和柱应用到3-甲基-喹噁啉-2-羧酸（methyl-3-quinoxaline-2-carboxylic acid,MQCA）的净化中,建立鱼虾中MQCA的免疫亲和柱净化-超高效液相色谱-串联质谱的快速分析方法。匀质好的样品经2 mol/L盐酸溶液酸解后,将提取液pH值调节至7～8,经过免疫亲和柱富集和净化后,采用超高效液相色谱-串联质谱测定,外标法定量。以甲醇-0.1%甲酸溶液为流动相,梯度洗脱分离,电喷雾正离子多反应监测模式监测。结果显示,水产品中MQCA在1.0～50.0 ng/mL范围内呈良好线性,线性相关系数大于0.995,定量限为1.0 μg/kg。MQCA在1.0、5.0 μg/kg和20.0 μg/kg 3 种添加水平条件下的加标回收率为74.2%～86.5%,相对标准偏差小于10%。结果表明本方法重复性好、灵敏度高,适合水产品中MQCA的实际测定。     

气相色谱-质谱联用检测进出口水产品中氟乐灵残留

采用液液萃取的前处理方式,以气相色谱-质谱联用仪(gas chromatography- mass spectrometry,GC-MS)检测水产品中氟乐灵的残留量。水产品经过匀质,丙酮提取,正己烷进行液液分配,弗罗里硅土柱净化后,用气相色谱-质谱联用仪进行测定和确认,外标法定量。该方法在5～100μg/L质量浓度范围内,相关系数R2为0.99996,具有良好的线性关系,检测限均为1.0μg/kg。分别在鳗鱼、梭子蟹、黄花鱼、印度虾和蛤蜊5种水产品中添加1～4μg/L氟乐灵,回收率在82.0%～93.6%之间。该方法操作简单、灵敏度高,可以满足水产品中氟乐灵的定性定量检测要求。     

超高效液相色谱串联静电场轨道阱质谱快速检测白酒中10种甜味剂

建立基于超高效液相色谱-静电场轨道阱质谱快速筛查确证白酒中安赛蜜、甜蜜素、甘露糖、山梨糖醇、糖精钠、阿斯巴甜、阿力甜、麦芽糖醇、纽甜、三氯蔗糖等10种甜味剂的方法。样品用纯水稀释后直接进样,经ACQUITY UPLC HSS T3色谱柱分离,甲醇和0.01 mol/L乙酸铵水溶液为流动相进行梯度洗脱,采用负离子模式,通过全扫描与二级碎片离子对白酒中10种目标化合物进行定性定量检测。结果表明,10种甜味剂的线性相关系数均大于0.99,基质加标回收率范围为87.3%~106.2%,相对标准偏差RSD值在2.4%~6.2%,检测限为1.0~3.0μg/kg。该方法简便、快速,定性定量准确可靠,可作为白酒中10种甜味剂的快速筛查方法。     

SPE-HPLC-ESI-MS-MS测定常见焙烤及油炸食品中丙烯酰胺的含量

目的：建立一种焙烤和油炸食品中丙烯酰胺的固相萃取-高效液相色谱-电喷雾离子化串联质谱检测方法。方法：样品用水提取,Cleanert SLE固相萃取柱净化,高效液相色谱-电喷雾离子化串联质谱测定,内标法定量。结果：在0.01～3.00 mg/L范围内,线性相关系数大于0.998,方法的检出限为1.0 μg/kg。在3 个添加量（10、100、1 000 μg/kg）的平均回收率为96.8%,相对标准偏差为2.7%。结论：该方法简便、准确、稳定,已实际应用于测定焙烤和油炸食品中丙烯酰胺的含量。