鳗鱼油的脂肪酸组成分析

鳗鱼加工下脚料（头、骨等）所得鱼油经甲酯化处理后，用GC和GC-MS进行了脂肪酸的组成分析，共签定出27个组分，它们占色谱峰总面积的97．9％。其主组分为油酸、棕榈酸、棕榈油酸，并含有廿碳五烯酸、廿二碳六烯酸，与鳗鱼肉中油的化学组成类似，具有开发利用的价值。     

高效液相色谱法检测鳗鱼中氟苯尼考残留量

建立了鳗鱼肌肉中氟苯尼考残留的分析方法。采用乙酸乙酯作为提取剂,提取液挥干后溶于缓冲液中,经正已烷脱脂、C18SPE小柱净化后,采用高效液相色谱进行分析,方法在1～200ng之间呈线性相关;相关系数r=0．9999。对于0．05、0．10、0．50mg／kg 3个添加水平,平均回收率均在90％以上,相对标准偏差为4．24％～7．36％,方法检出限和定量限分别为9．1μg/kg和22．3μg／kg。     

高效液相色谱-串联质谱联用测定鳗鱼中孔雀石绿、结晶紫及其代谢物残留量

应用高效液相色谱与串联质谱联用技术测定了鳗鱼中孔雀石绿(MG)、结晶紫(CV)及其代谢物(LMG,LCV)的残留量.样品用乙腈提取后,经脱脂、浓缩及净化处理,所得残渣用流动相混合液溶解后,通过Acquity UPLCTM BEH C18色谱柱分离,流出液供串联质谱测定,用氘代孔雀石绿及氘代无色孔雀石绿作内标参比定量.结果表明:对MG、LMG、CV、LCV四种化合物在0.1～10.0 μg·L-1范围内均呈线性关系,在0.5 μg·kg-1及2 μg·kg-1的标准加入水平下进行了回收试验,所得回收率在86.5%～91.8%之间,方法的检出限为0.1 μg·L-1(对MG及LMG)和0.5 μg·L-1(对CV及LCV),测定结果的相对标准偏差(n=7)≤7%.     

HPLC法测定鳗鱼、猪肉和对虾中的痢特灵残留

在传统法的基础上，常量分析与微量分析技术有效地相结合，研究了测定动物性食品中痢特灵残留的快速ＨＰＬＣ法，用二氯甲烷提取样品中的痢特灵，浓缩提取液至干，８０％乙腈水溶液溶解残渣，在５ｍＬ离心管中用正已烷萃取、分离杂质，清液供ＨＰＬＣ分析用，方法回收率大于８０％，相对标准编差（ｎ＝６）小于８％。     

河豚鱼、鳗鱼和烤鳗中角黄素残留的超高效液相色谱法测定和超高效液相色谱-串联质谱法确证

建立了河豚鱼、鳗鱼和烤鳗中角黄素残留的超高效液相色谱测定方法和超高效液相色谱-串联质谱确证方法。样品用抗氧化剂焦性没食子酸保护,乙腈均质提取,正己烷液-液分配净化,超高效液相色谱-紫外检测器测定,外标法定量,超高效液相色谱-串联质谱法确证。测定方法采用BEHC18色谱柱(50 mm×2.1 mm,i.d.1.7μm),流动相为V(0.1%的甲酸)∶V(乙腈)=3∶97,检测波长470 nm。实验结果表明,角黄素在0.05~2.0 mg/L范围内线性关系良好(r=0.9999),在空白样品中,添加低、中、高3个浓度水平(0.05,0.1,1.0 mg/kg),角黄素的回收率均在82.52%~96.96%之间,相对标准偏差为6.9%~15%。方法的检出限(LOD)为0.02 mg/kg,定量限(LOQ)为0.05 mg/kg。串联质谱确证方法采用电喷雾(ESI)离子源,在正离子模式下以多反应监测(MRM)扫描方式检测,定性离子对565.5/203.2和565.5/133.1,定量离子对565.5/203.2。     

Large volume sample stacking capillary electrophoresis for metallothioneins analysis in eel liver

A large volume sample stacking procedure (LVSS) is developed here for metallothionein (MT) determinations in rabbit liver by using capillary electrophoresis with UV detection. A 10-time improvement in concentration-based LODs, when compared to the normal stacking mode (CE-UV analysis of samples solved in water), is achieved.The methodology is successfully applied to analysis of MTs in eel liver cytosolic extracts, preceded by an easy cleaning-up pre-treatment in order to eliminate the high salt content. Analysis of cytosol obtained from a group of eels previously exposed to Cd (induced group) resulted in several isoforms of MTs with differences in absorbance signal compared to a control group.     

液相色谱-质谱联用法分析检测鳗鱼中4种硝基呋喃代谢物

建立了液相色谱-质谱联用法(LC-MS)测定鳗鱼中4种硝基呋喃代谢物的快速方法。方法首先采用甲醇水溶液(V甲醇:V水=8:1)粗提鳗鱼中的呋喃唑酮代谢物(AOZ),呋喃它酮代谢物(AMOZ),呋喃西林代谢物(SC)和呋喃妥因代谢物(AH),再用2-硝基苯甲醛(2-NBA)作为衍生剂,使鳗鱼中的这4种硝基呋喃代谢物被成功衍生,并最终实现LC-MS的分离检测。结果表明,本方法高效灵敏,检出限低,AOZ和AMOZ的检出限分别可达到0.08、0.06ng/g,AH和SC的检出限分别为0.16ng/g和0.15ng/g,可很好地运用于鳗鱼企业内部及市场监管部门对水产品中硝基呋喃抗生素代谢物的检测分析。     

超高效液相色谱-串联质谱法测定鳗鱼中四环素类药物残留

5.0g水产品组织样品,用乙二胺四乙酸二钠的柠檬酸缓冲溶液提取,用正己烷去除脂肪后,经GL-PakPLS-2小柱净化,旋转蒸发器减压蒸干后,用甲醇-水(30+70)溶液溶解,样液用超高压液相色谱分离,电喷雾串联四级杆质谱进行检测,外标法定量。测定4种四环素类药物的线性范围均为5.0～100.0μg.L-1,在5,20,50μg.kg-1的3个添加水平范围内平均回收率为70.6%～93.4%,相对标准偏差(n=6)为6.3%～10.5%,方法测定下限(10S/N)可达5.0μg.kg-1。     

鳗鲡肌肉冻干粉中呋喃唑酮代谢物3-氨基-2-(噁)唑烷酮残留标准物质的研制

建立了鳗鲡肌肉冻干粉中3-氨基-2-噁唑烷酮(AOZ)残留分析标准物质的研制和定值方法。以约0.16mg/L呋喃唑酮对鳗鲡进行药浴给药,使呋喃唑酮在鱼体中代谢,从而使鳗鲡肌肉中含有一定浓度的呋喃唑酮代谢物AOZ。经冻干、真空包装及辐照等处理后获得1批400个独立包装的肌肉冻干粉样本。经过均匀性与稳定性检验,由11家实验室采用同位素稀释液相色谱-串联质谱法进行协同定值,并进行了不确定度评估,已被国家质检总局批准确为国家二级标准物质。     

Determination of neonicotinoid insecticides residues in eels using subcritical water extraction and ultra-performance liquid chromatography–tandem mass spectrometry

A rapid, sensitive, and environmental-friendly multi-residue method has been developed for the simultaneous determination of seven neonicotinoid insecticides (dinotefuran, nitenpyram, thiamethoxam, imidacloprid, clothianidin, acetamiprid, and thiacloprid) residues in eel samples. Subcritical water extraction was investigated as a novel and alternative technology for the extraction of neonicotinoids from eel matrices and the results were compared with the conventional ultrasonic and shaking extraction. The target compounds were identified and quantitatively determined by ultra-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC–MS/MS) operated in multiple reaction monitoring mode. Under the current optimized chromatographic conditions, each LC run was completed in 5 min. Average recoveries of the seven analytes from fortified samples ranged between 84.6% and 102.0%, with relative standard deviations (RSD) lower than 10.8%. The limits of detection (LODs) and quantification (LOQs) for neonicotinoids were in the ranges of 0.12–0.36 μg kg⁻¹ and 0.42–1.12 μg kg⁻¹, respectively. The proposed method is fast, sensitive, easy to perform, water-based thus more environmentally acceptable, making it applicable for high-throughput monitoring of insecticides residues in aquatic products.