QuEChERS-超高效液相色谱-四极杆/静电场轨道离子阱质谱法检测鱼肉中15种降血脂药

建立了QuEChERS结合超高效液相色谱-四极杆静电场轨道离子阱质谱测定鱼肉中15种降血脂药残留量的方法。样品前处理采用优化的QuEChERS法,通过响应面法优化了吸附剂材料乙二胺-N-丙基硅烷(PSA)(20、60、100、140和180 mg)、C18(40、100、160、220和280 mg)及乙酸钠(0.2、0.6、1.0、1.4和1.8 g)的用量。液相色谱采用XBridge-C18色谱柱(100 mm×2.1 mm, 3.5μm),以乙腈-0.1%(v/v)甲酸水溶液(含1.5 mmol/L乙酸铵)为流动相进行梯度洗脱,采用加热电喷雾电离(HESI)源,在正、负离子同时检测模式下以全扫描(full-MS)和二级质谱扫描(dd-MS²)方式对目标物进行定性和定量分析。15种降血脂药在各自范围内线性关系良好,相关系数(R²)大于0.99;检出限(LOD,S/N=3)和定量限(LOQ,S/N=10)分别为0.2～1.0μg/kg和0.3～3.1μg/kg;鱼肉样品中15种降血脂药在LOQ、2倍LOQ和10倍LOQ水平下的加标回收率为7...     

高效液相色谱-线性离子阱/静电场轨道阱高分辨质谱法快速筛查和确证纺织品中禁用的偶氮染料

建立了高效液相色谱-线性离子阱/静电场轨道阱高分辨质谱(HPLC-LTQ/Orbitrap MS)快速筛查确证纺织品中禁用的偶氮染料的方法。样品在柠檬酸缓冲液中由连二亚硫酸钠还原成芳香胺,经硅藻土提取柱净化后,用Acquity UPLC BEH C18柱(50 mm×2.1 mm, 1.7 μm)分离,以甲醇和0.1%(v/v)甲酸作为流动相进行梯度洗脱,电喷雾正离子(ESI+)模式电离,高分辨质谱一级全扫描用于筛选分析,数据依赖扫描模式的二级碰撞诱导解离(CID)谱图用于确证,对纺织品样品中的偶氮染料进行定性鉴别。在0.05~2.00 mg/L范围内,21种致癌芳香胺的线性相关系数均大于0.99。通过实际样品的加标回收测定,回收率范围为65.5%~111.5%,相对标准偏差(n=6)为0.87%~2.49%。该方法的定量限可以达到0.08 mg/kg,可用于纺织品中禁用偶氮染料的实际检验工作。     

Structural characterization of ether lipids from the archaeon Sulfolobus islandicus by high‐resolution shotgun lipidomics

The molecular structures, biosynthetic pathways and physiological functions of membrane lipids produced by organisms in the domain Archaea are poorly characterized as compared with that of counterparts in Bacteria and Eukaryota. Here we report on the use of high‐resolution shotgun lipidomics to characterize, for the first time, the lipid complement of the archaeon Sulfolobus islandicus. To support the identification of lipids in S. islandicus, we first compiled a database of ether lipid species previously ascribed to Archaea. Next, we analyzed the lipid complement of S. islandicus by high‐resolution Fourier transform mass spectrometry using an ion trap‐orbitrap mass spectrometer. This analysis identified five clusters of molecular ions that matched ether lipids in the database with sub‐ppm mass accuracy. To structurally characterize and validate the identities of the potential lipid species, we performed structural analysis using multistage activation on the ion trap‐orbitrap instrument as well as tandem mass analysis using a quadrupole time‐of‐flight machine. Our analysis identified four ether lipid species previously reported in Archaea, and one ether lipid species that had not been described before. This uncharacterized lipid species features two head group structures composed of a trisaccharide residue carrying an uncommon sulfono group (?SO₃) and an inositol phosphate group. Both head groups are linked to a glycerol dialkyl glycerol tetraether core structure having isoprenoid chains with a total of 80 carbon atoms and 4 cyclopentane moieties. The shotgun lipidomics approach deployed here defines a novel workflow for exploratory lipid profiling of Archaea. Copyright © 2015 John Wiley & Sons, Ltd.     

超高效液相色谱-四极杆/静电场轨道阱高分辨质谱快速筛查及定量分析保健品中11种非法添加降糖药物

基于超高效液相色谱-四极杆/静电场轨道阱质谱建立了保健品中11种非法添加化学降糖药(那格列奈、盐酸吡格列酮、格列喹酮、格列齐特、格列吡嗪、格列本脲、盐酸二甲双胍、瑞格列奈、盐酸苯乙双胍、盐酸罗格列酮、格列美脲)的快速筛查和定量分析方法。样品采用甲醇提取,C18色谱柱(100 mm×4.6 mm, 2.7 μm)分离,用10 mmol/L乙酸铵水溶液和乙腈进行梯度洗脱,正离子模式扫描。化合物一级质谱的分辨率为70000,二级质谱分辨率为17500。实验结果表明,11种化合物在0.005~0.5 mg/L范围内具有良好的线性(线性相关系数均大于0.99),各降糖类药物检出限为2.7~5.1 μg/kg,回收率为87.3%~98.3%,相对标准偏差为2.18%~5.21%。本方法具有准确、简便、快速的特点,可用于降糖类保健品中11种降糖药物的定性筛查和定量分析。     

超高效液相色谱-线性离子阱/静电场轨道阱高分辨质谱法测定纺织品中的游离态致癌芳香胺

建立了超高效液相色谱-线性离子阱/静电场轨道阱高分辨质谱(UPLC-LTQ/Orbitrap MS)同时测定纺织品中24种游离态致癌芳香胺的方法。样品经二氯甲烷超声提取并稀释后,用ZORBAX SB-C₁₈色谱柱(150 mm×2.1 mm, 5 μm)分离,以0.1%甲酸水溶液和甲醇为流动相,电喷雾正离子(ESI⁺)模式电离,以准分子离子峰的精确质量数和保留时间定性,以提取的色谱图峰面积定量。在0.5~500 μg/L范围内,24种芳香胺的线性相关系数(R²) 大于0.99,样品加标回收率为87.8%~105.6%,相对标准偏差为1.6%~3.4%。方法检出限为0.5~1 μg/kg。应用本方法检测山东地区进出口含氨纶纺织品样品14个,在5个样品中检出游离态芳香胺4,4'-二氨基二苯甲烷,含量范围为0.21~25.6 mg/kg。     

Simultaneous determination of dyes in wines by HPLC coupled to quadrupole orbitrap mass spectrometry

A new method combining the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method with ultra high performance liquid chromatography and ESI quadrupole Orbitrap high‐resolution MS was developed for the highly accurate and sensitive screening of 69 dyes in wines. Response surface methodology was employed to optimize the QuEChERS sample preparation method for the determination of 69 different analytes in wines for the first time. After optimization, the maximum predicted recovery was 99.48% rate for canacert indigo carmine under the optimized conditions of 10 mL acetonitrile, 1.45 g sodium acetate, 107 mg primary secondary amine, and 96 mg C₁₈. For the matrices studied, the recovery rates of the other 68 compounds ranged from 87.2–107.4%, with coefficient of variation < 6.4%. The mass accuracy typically obtained is routinely better than 1.6 ppm and only needed to be calibrated once a week. The LODs for the analytes are in the range 1–1000 μg/kg. This method has been successfully applied on screening of dyes in commercial wines, and it is very useful for the fast screening of different food additives.     

超高效液相色谱-四极杆-静电场轨道阱高分辨质谱快速筛查与确证猪尿中74种抗生素及其他化合物

采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Exactive Orbitrap)建立了猪尿中74种抗生素及其他化合物的快速筛查与确证方法。猪尿样品经高速离心并稀释后,以Agilent SB C_(18)色谱柱(3.0 mm×100 mm,1.8μm)分离,0.1%甲酸水溶液和0.1%甲酸乙腈溶液为流动相进行梯度洗脱。结合精确分子质量数、保留时间和二级特征碎片离子对目标化合物进行筛查与确证。74种目标药物在各自的浓度范围内呈良好线性(r~20.99),检出限(LOD)为10 ng/mL,在检出限加标浓度下,回收率集中在55.8%～120%,相对标准偏差(RSD)为1.3%～21%。该方法简便、快速、灵敏、准确,适用于猪尿中多种抗生素及其他化合物的定性确证,有利于掌握养殖业用药情况。     

亲水相互作用色谱-四极杆/静电场轨道阱高分辨质谱检测奶粉中的氟乙酸钠

基于亲水相互作用色谱-四极杆/静电场轨道阱高分辨质谱系统,建立了奶粉中氟乙酸钠的快速筛查和定量检测方法。奶粉样品用水溶解后经正己烷脱脂,用6 mol/L硫酸调节pH值,经乙腈提取后用亲水相互作用色谱-四极杆/静电场轨道阱高分辨质谱进行分析。结果表明,该方法在1~50 μg/kg范围内线性关系良好,定量限为1 μg/kg,平均回收率为85.5%~106%,相对标准偏差为5.20%~13.6%。该方法可用于配方奶粉、脱脂奶粉和乳清粉等奶粉产品中氟乙酸钠的快速筛查和定量分析。