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51.
建立了鳗鱼肌肉中磺胺类药物残留的高效液相色谱柱后衍生分析方法。鳗鱼肌肉样品经乙腈和水提取,液- 液分配和固相萃取净化浓缩后,采用高效液相色谱柱后衍生法检测磺胺类药物经C18 色谱柱分离,在柱后反应单元中与荧光胺反应,生成具有荧光特性的分子,荧光检测器检测方法定量检测限为2.0μg/kg,磺胺浓度在0.005~0.2μg/ml 范围内线性关系良好(r ≥ 0.9998),磺胺浓度范围在2.0~50.0μg/kg 鳗鱼肌肉加标样,日内和日间回收率为85.1%~90.2%,相对标准偏差2.74%~6.04%。实验结果表明,该检测方法适用于低浓度水平鳗鱼肌肉中磺胺类药物残留检测。 相似文献
52.
Junwei Liu Guozhen Fang Yan Zhang Wenjie Zheng Shuo Wang 《Journal of the science of food and agriculture》2009,89(1):80-87
BACKGROUND: An enzyme‐linked immunosorbent assay (ELISA) based on polyclonal antibodies with enhanced chemiluminescent (ECL) detection of sulfonamides in food samples has been optimised and characterised. The specificity of the assay was assessed by determining cross‐reactivities with a set of 16 sulfonamides. The aim of this study was to develop a method for determining sulfonamides with high sensitivity. RESULTS: The sensitivity of the developed ECL‐ELISA was higher than that of colorimetric ELISA. The sensitivities of five of the sulfonamides (sulfisozole, sulfathiazole, sulfameter, sulfamethoxypyridazine and sulfapyridine) ranged from 0.73 to 2.92 µg L?1, with limits of detection of 0.10–0.43 µg L?1. The coefficients of variation of intra‐assay and inter‐assay studies carried out over 5 days were mostly less than 10%. Recovery studies of chicken muscle and pig muscle were performed with simple and rapid extraction. Good recoveries (62.1–110.3%) were achieved and the results correlated well with those obtained using high‐performance liquid chromatography analysis. CONCLUSION: This study has provided an effective analytical technique for the rapid and reliable determination of residues of sulfisozole, sulfathiazole, sulfameter, sulfamethoxypyridazine and sulfapyridine in food samples with high sensitivity. To the authors' knowledge, this is the first report on chemiluminescent ELISA for sulfonamide analysis. Copyright © 2008 Society of Chemical Industry 相似文献
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V. Jiménez R. Companyó 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(7):969-977
A feasibility study of the preparation of quality control materials for the analysis of medicated feeds has been carried out. Two analytical methodologies for the analysis of sulfonamides in feeds were developed, validated and applied to homogeneity and stability studies. Pig feeds spiked with sulfadiazine and sulfadimidine were prepared. The drugs were spiked at 500 µg g?1, representing what can be expected in a commercial medicated feed, and at 2 and 5 µg g?1, which roughly correspond to drug-free feeds cross-contaminated during the fabrication process. The homogeneity of both the bulk and the bottled materials was verified. A stability study of the materials containing 2 and 5 µg g?1 of sulfonamides was carried out over an 18-month period at room temperature, at 4°C and ?20°C. The determination of sulfadiazine and sulfadimidine in samples coming from these homogeneity and stability studies of the quality control materials was carried out by high-performance liquid chromatography (HPLC) with either ultraviolet light or fluorimetric detection, depending on the concentration of the analytes in the samples. 相似文献
55.
设计合成了高能量密度材料1,4-二硝基呋咱并[3,4-b]哌嗪(DNFP)。即以N,N'-二叔丁基乙二胺为起始原料,低温条件下与二氯乙二肟缩合环化生成1,4-二叔丁基哌嗪-2,3-二酮肟(PDO—tB),而后在氢氧化钠的乙二醇溶液中高温反应脱水环化得1,4-二叔丁基呋咱并[3,4-b]哌嗪,经98%硝酸和硫酸的混酸体系硝解合成出DNFP,总收率32.6%,采用红外光谱、核磁共振谱、元素分析对DNFP和中间体结构进行了表征;改进了PDO—tB的合成工艺条件,加料方式由一次性加入改为缓慢滴加,并确定了适宜的冷浴温度为-18℃;研究了不同硝解体系对反应的影响,确定了适宜的硝解体系为硝硫混酸,硝解收率为61.7%。 相似文献
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目的建立同时测定蜂蜜中15种喹诺酮和17种磺胺类药物残留的液相色谱-串联质谱(liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)检测方法。方法样品经过磷酸盐缓冲溶液(pH=8)提取,过HLB(hydrophile-lipophile balance)固相萃取柱净化。以CORTECS C18色谱柱(2.1 mm×100 mm,1.6μm)分离,以5 mmol乙酸铵、0.1%甲酸水(A)和0.1%甲酸-乙腈(B)作为流动相进行梯度洗脱。质谱分析以电喷雾为离子源(electrospray ionization,ESI+),采用多反应监测(multiple reaction monitoring,MRM)。结果本方法在15 min内完成32种目标化合物的分离。15种喹诺酮和17种磺胺类药物在1.0、5.0和10.0μg/kg添加水平的回收率为54.9%~122.5%,相对标准偏差(relative standard deviation,RSD)小于18.7%(n=6),方法检出限为0.4μg/kg,定量限为1.0μg/kg。结论该方法快速、准确、灵敏,适合测定蜂蜜中喹诺酮和磺胺类药物残留。 相似文献
58.
目的 建立基质固相分散-高压液相色谱-高分辨质谱测定猪肉中22种磺胺类药物残留量的测定方法, 包括磺胺苯酰、磺胺醋酰、磺胺氯哒嗪、磺胺嘧啶、磺胺间二甲氧嘧啶、磺胺二甲嘧啶、磺胺甲基嘧啶、磺胺多辛、磺胺间甲氧嘧啶、磺胺甲氧哒嗪、磺胺对甲氧嘧啶、磺胺甲噁唑、磺胺甲噻二唑、磺胺二甲噁唑、磺胺苯吡唑、磺胺吡啶、磺胺喹噁啉、磺胺噻唑、磺胺异噁唑、磺胺胍、甲氧苄啶、磺胺索嘧啶。方法 猪肉样品与弗罗里硅土混合, 研磨均匀, 装入空的固相萃取管中, 用15 mL 1%乙酸二氯甲烷: 乙酸乙酯(1∶3, v/v)洗脱, 洗脱液用氮气吹干, 残渣用1 mL乙腈: 10 mmol/L乙酸铵溶液(15∶85, v/v)溶解。加入1 mL正己烷混合离心, 取下层溶液, 经0.22 μm滤膜过滤后用Agilent Poroshell 120 EC-C18(2.1 mm×150 mm, 2.7 μm)色谱柱分离, 高分辨质谱测定。结果 22种磺胺类药物在 10~100 μg/kg范围内线性关系良好, 相关系数r>0.99, 除磺胺甲噻二唑、甲氧苄啶和磺胺脒/磺胺胍加标回收率小于40%外, 其余均大于60%, 定量限为 5~10 μg/kg。结论 本方法具有前处理快速、高效、有机试剂用量少、成本小等优点, 适用于猪肉中磺胺类药物残留量的测定。 相似文献
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Renè Hommelsheim Robin van Nahl Lena M. Hanek Jas S. Ward Kari Rissanen Carsten Bolm 《Advanced Synthesis u0026amp; Catalysis》2024,366(4):717-724
A palladium-catalyzed domino reaction of 2-azidosulfonamides and isocyanides enables the synthesis of 3-amino-substituted 1,2,4-benzothiadiazine 1,1-dioxides at room temperature. By applying commercially available Pd(dba)2 in catalyst loadings as low as 1.0 mol%, a variety of 21 differently substituted 2H-1,2,4-benzothiadiazine 1,1-dioxides can be prepared within 2 h. Moreover, the developed protocol gives access to the related 4H heterocycles. 相似文献