液相色谱-电喷雾串联质谱法检测鸡组织中5种聚醚类药物残留

建立了鸡组织中聚醚类药物多残留检测的高效液相色谱-电喷雾串联质谱方法。采用甲醇提取鸡组织中的拉沙洛菌素、盐霉素、莫能菌素、甲基盐霉素和马杜霉素,经硅胶柱净化,以乙腈(含0.1%甲酸)-0.1%甲酸水溶液(体积比为97:3)为流动相,Symmetry Shield RP18作为色谱分析柱,多反应监测(MRM)正离子扫描方式进行质谱检测。当5种聚醚类药物的添加水平为鸡肉0.1～1500 μg/kg、鸡肝0.2～4500 μg/kg时,平均回收率为71.6%～99.1%,日内测定的相对标准偏差(RSD)(n=5)为3.2%～10.7%,日间RSD(n=3)为4.6%～14.7%。2种鸡组织中5种聚醚类药物的定量限为0.1～1.0 μg/kg。该方法的灵敏度、准确度和精密度均符合兽药残留分析技术的要求,适用于鸡肉和鸡肝中5种聚醚类药物的多残留检测。     

超高效液相色谱-串联质谱法同时测定调味料中的17种防腐剂和抗氧化剂

建立了超高效液相色谱-串联质谱(UPLC-MS/MS)同时测定调味料中11种防腐剂和6种抗氧化剂的定性、定量分析方法。低脂肪和中等脂肪含量的调味料样品用饱和NaCl水溶液(用磷酸调pH为2～3)稀释混合均匀,然后用乙腈提取,正己烷液-液萃取净化(中等脂肪含量的样品提取液还需经C8固相萃取柱进一步的净化处理);脂肪含量高的样品先用正己烷稀释,再用饱和NaCl水溶液(用磷酸调pH为2～3)溶解样品,然后用乙腈提取,提取液进一步经C8固相萃取柱净化处理。提取液经C18反相色谱柱(150 mm×2.1 mm, 1.7μm)分离,流动相为20 mmol/L乙酸铵水溶液和乙腈,梯度洗脱,以电喷雾离子源负离子多反应监测(MRM)模式进行MS/MS检测。17种分析物在线性范围内具有较好的线性关系,相关系数r≥0.9955,其定量限(LOQ,信噪比为10)为0.05～5 mg/kg;空白样品中的添加回收率为79.7%～118%,精密度(以相对标准偏差计)为0.57%～13.1%。该方法适用于调味品中防腐剂和抗氧化剂的检测。     

固相萃取-超高效液相色谱-电喷雾串联质谱法同时测定地表水中9种微囊藻毒素

建立了固相萃取-超高效液相色谱-电喷雾串联三重四极杆质谱(SPE-UPLC-ESI-MS/MS)联用技术分析水中9种微囊藻毒素的方法。样品经SPE提取和净化后,以Waters ACQUITY UPLCTM BEH C18色谱柱为分离柱,以含0.1%甲酸乙腈和含0.1%甲酸水作为流动相进行梯度洗脱,电喷雾离子源电离、正离子多反应监测模式质谱进行定性和定量分析。9种微囊藻毒素在0.1～50 μg/L或0.5～100 μg/L质量浓度范围内线性良好,相关系数为0.9990～0.9998,方法的检出限(以3倍信噪比计)为0.1～0.5 ng/L;高、中、低3个添加水平的回收率为75.8%～109%,相对标准偏差为0.49%～10.0%。结果表明,该方法灵敏、准确,检测范围广,分析速度快。应用该方法检测了杭州市两处水库水样中的微囊藻毒素,分别检出了3种和8种微囊藻毒素。     

超高效液相色谱-电喷雾串联质谱法测定动物饲料中的大环内酯类和林可胺类抗生素

建立了动物饲料中竹桃霉素、红霉素、吉他霉素、交沙霉素、罗红霉素、泰乐菌素6种大环内酯和林可霉素、克林霉素2种林可胺抗生素的超高效液相色谱-电喷雾串联质谱(UPLC-ESI-MS/MS)检测方法。饲料样品采用甲醇提取,Oasis HLB固相萃取柱富集净化,Waters Acquity UPLC BEH C18色谱柱分离,以0.1%甲酸和乙腈为流动相进行梯度洗脱,流速为0.3 mL/min,正离子模式扫描,多反应监测模式检测,外标法定量。实验结果表明,8种药物在1～100 μg/L范围内具有良好的线性关系。在空白饲料样品中分别添加1、10和100 μg/kg 3个加标水平的8种药物,其平均回收率为68.6%～95.2%,相对标准偏差(RSD)为4.9%～11.8%,定量限均为1 μg/kg。结果表明,该方法简便快速、灵敏度高,适用于动物饲料中大环内酯类和林可胺类抗生素的同时检测。     

Simultaneous determination nucleosides in marine organisms using ultrasound-assisted extraction followed by hydrophilic interaction liquid chromatography-electrospray ionization time-of-flight mass spectrometry

A new method has been developed based on ultrasound-assisted extraction (UAE) followed by hydrophilic interaction chromatography (HILIC) and electrospray ionization time-of-flight mass spectrometry (ESI-TOF/MS) for the simultaneous determination of 16 nucleosides and nucleobases in medicinal extracts of various marine organisms. The separation was achieved on a Venusil HILIC column (250×4.6 mm id, 5 μm) and gradient elution using a solution of acetonitrile and buffer (0.20% formic acid and 20 mmol/L ammonium acetate) as the mobile phase. Identification of the 16 target nucleosides and nucleobases was based on the retention time, UV spectra, and mass measurements of the protonated molecules ([M+H](+)) and main fragment ions (ESI-TOF/MS). In addition, non-target compounds of 2'-deoxyinosine and four other amino acids were also tentatively identified by ESI-TOF/MS. The 16 target compounds were quantified by HILIC-ESI-TOF/MS under optimized mass conditions. All calibration curves showed good linearity (r(2)>0.9951). The recoveries were 84.72-124.10%, and the limits of detection of the 16 target compounds were 0.6-130.0 ng/mL. The developed method was applied to quantify the target compounds in 15 batches of various marine organisms. The method has potential applicability for the identification and determination of highly polar and low-concentration active compounds in marine organisms.     

超高效液相色谱-串联质谱法同时测定聚合物食品包装材料中8种添加剂

建立了同时测定聚合物食品包装材料中8种常用添加剂Irgafos 168、Irganox 1010、Irganox 1076、丁基羟基茴香醚（BHA）、没食子酸丙酯（PG）、没食子酸十二酯（DG）、叔丁基对苯二酚（TBHQ）和苯三唑甲酚（UV-326）的超高效液相色谱-串联质谱方法。试样以二氯甲烷为溶剂进行超声提取;采用Waters BEH-C18柱（50 mm×2.1 mm,1.7 μm）分离,以0.05%甲酸水溶液和甲醇为流动相进行梯度洗脱;采用电喷雾离子源正、负离子切换模式和多反应监测模式进行检测。8种添加剂在相应的质量浓度范围内定量离子的峰面积与质量浓度均呈良好线性关系（相关系数R²均大于0.993）,回收率为63.9%~127.0%,相对标准偏差（RSD,n=6）≤15.8%,检出限（S/N=3）为0.13~5.50 μg/L,定量限（S/N=10）为0.45~17.50 μg/L。该方法简便快捷、灵敏度高,适合食品包装材料中常用添加剂的分析测定。     

固相萃取-超高效液相色谱-电喷雾串联质谱法同时检测尿样中的麻黄碱和N-甲基麻黄碱

建立了固相萃取-超高效液相色谱-电喷雾串联质谱(SPE-UPLC-ESI MS/MS)联用方法,定量测定尿样中的麻黄碱和N-甲基麻黄碱。样品经Oasis MCX柱提取、纯化和富集后,采用电喷雾(ESI)离子源电离,正离子多反应监测(MRM)模式质谱进行定性和定量分析。麻黄碱和N-甲基麻黄碱在0.0250~2.50 μg/L质量浓度范围内线性关系良好,线性相关系数分别为0.9998和0.9992,提取回收率高于80%,提取效率的RSD小于5.0%,检出限均达到0.01 μg/L,可大大延长尿样检材中麻黄碱和N-甲基麻黄碱的检测周期。结果表明,该方法快速、准确,为尿液中痕量麻黄碱和N-甲基麻黄碱的分析提供了灵敏的分析方法。     

超高效液相色谱-电喷雾串联四极杆质谱法同时测定配合饲料中29种兽药

建立了同时测定配合饲料中喹诺酮类、磺胺类、大环内酯类和硝基呋喃类共计29种兽药的超高效液相色谱-电喷雾串联四极杆质谱(UPLC-ESI-MS/MS)检测方法。饲料样品用甲醇-乙腈(1:1, v/v)混合溶液提取,提取液经Oasis HLB固相萃取柱净化,采用UPLC-ESI-MS/MS检测。以甲醇和含0.1%(v/v)甲酸的水溶液作为流动相,进行梯度洗脱,用C18色谱柱分离,正离子模式扫描,多反应监测模式检测。29种兽药在0.01～5.0 mg/L范围内线性关系良好,相关系数(r)均大于0.99;在复合预混饲料、全价配合饲料、浓缩饲料中4个添加水平下29种兽药的平均回收率在61.2%～94.3%范围内,相对标准偏差(RSD)为2.2%～15.0%;方法的检出限(以信噪比大于10计)为0.01 mg/kg或0.05 mg/kg。该方法简便、快速、准确,重现性好,灵敏度高,适用于配合饲料中多种兽药的同时检测。     

Simultaneous determination of fluoroquinolone, sulfonamide, and trimethoprim antibiotics in wastewater using tandem solid phase extraction and liquid chromatography-electrospray mass spectrometry

A robust and sensitive method for the detection of fluoroquinolones, sulfonamides and trimethoprim has been developed. Wastewater samples were acidified and extracted through an anion-exchange cartridge in tandem with a hydrophilic-lipophilic balance (HLB) cartridge, a procedure that reduced interferences from wastewater organic matter. The extracted antibiotics were analyzed using liquid chromatography electrospray mass spectrometry and selected ion monitoring. Quantification of antibiotics was assessed both by internal standard and standard addition methods. Average recoveries for a range of wastewater matrices were 37 to 129% for a 1 microg/L spiking concentration. The method detection limits (MDLs) of antibiotics in deionized water, final and secondary effluent ranged from 2 to 7 ng/L, from 20 to 50 ng/L, and from 30 to 90 ng/L, respectively. Assessment of matrix interference shows that signal suppression and MDL increases with higher amounts of organic matter in the sample. Analyses of samples from two municipal wastewater treatment plants indicate that ciprofloxacin, ofloxacin, sulfamethoxazole and trimethoprim are present in the secondary effluents at median concentrations of 100-160, 205-305, 395-575, and 40-705 ng/L, respectively.     

同位素稀释液相色谱-串联质谱法准确测定猪肉中的氯霉素

建立了同位素稀释质谱测定猪肉中氯霉素残留的方法,对影响溶剂提取、萃取净化、液相色谱-质谱检测方法准确度的因素进行了量化与优化。猪肉样品经液氮冷冻粉碎,加入氯霉素-D5同位素内标和0.1 mol/L醋酸钠缓冲溶液(pH 5),用乙酸乙酯提取4次,正己烷脱脂,HLB固相萃取小柱净化后采用负离子多反应监测模式下的液相色谱-质谱技术检测。方法的线性范围为0.01～0.5 ng/g,相关系数r2大于0.999;检出限和定量限分别为0.004 ng/g和0.02 ng/g;在0.02 ng/g和1.0 ng/g加标水平的回收率(n=3)分别为95.2%～109.1%和99.7%～102.5%;日内和日间相对标准偏差均小于2%。研究了氯霉素及氯霉素-D5的基体效应,测得不同流动相和稀释溶剂组成时基体效应因子k的范围在0.950～1.015之间。研究结果对同位素稀释质谱痕量残留检测结果准确度的控制、方法的建立与验证具有参考意义。     

高效液相色谱串联质谱法测定牛奶中林可酰胺类和大环内酯类抗生素残留量的研究

建立了牛奶样品中洁霉素、氯洁霉素、红霉素、螺旋霉素、交沙霉素、泰乐菌素、竹桃霉素等7种林可酰胺类及大环内酯类药物残留量的确证方法。用乙腈萃取样品中7种林可酰胺类及大环内酯类抗生素,然后用正己烷脱脂,旋转蒸发仪浓缩,以Luna C18(2)色谱柱分离,在正离子模式下以电喷雾电离串联质谱仪进行测定。在20、50、200μg/kg 3个浓度水平进行验证试验,方法的线性范围为20~200μg/kg,总体平均回收率为74.5%~97.5%,相对标准偏差为2.7%~11.3%。该方法各项技术指标满足国内外法规的要求,可用于牛奶样品中林可酰胺类及大环内酯类抗生素残留量的确证检测。     

Simultaneous determination of tetracylines and quinolones antibiotics in egg by ultra-performance liquid chromatography-electrospray tandem mass spectrometry

We report here an ultra-performance liquid chromatography coupled with tandem mass spectrometric (MS/MS) method for the simultaneous quantitation of multiclass veterinary drugs in egg. The analysis of the target compounds, including 7 tetracyclines and 4 types of quinolones, may be accomplished in 15 min of total run time. The egg was extracted with ethylenediaminetetraacetic acid-Mcllvaine buffer solution and further purified using a polymer-based Oasis HLB solid-phase extraction cartridge. A C18 column was used to separate the analytes followed by MS/MS using an electrospray ion source. The overall average recoveries of the analytes based on matrix-fortified calibration ranged from 71 to 112% with acceptable relative standard deviations of <20% for 6 trials. For all of the target compounds, the limits of quantitation ranged between 0.02 and 4.29 microg/kg. The proposed method is sufficiently sensitive and highly selective.     

液相色谱-电喷雾串联质谱法同时检测鸡组织中5种抗病毒类药物的残留量

建立了鸡组织中抗病毒类药物多残留检测的液相色谱-电喷雾串联质谱法(LC-ESI-MS/MS)。采用三氯乙酸-乙腈溶液提取鸡组织中的金刚烷胺、金刚乙胺、美金刚、咪喹莫特和吗啉胍,离心过滤后经强阳离子交换柱(SCX)净化,色谱柱Xamide(100 mm×2.1 mm, 5 μm)分离,多反应监测(MRM)正离子扫描方式进行质谱检测。结果表明,鸡组织与鸡肝中5种药物的检出限为0.06～0.30 μg/kg,定量限为0.2～1.0 μg/kg。当5种药物的添加水平为0.2～10.0 μg/kg时,在鸡肉中的平均回收率为72.3%～94.2%,相对标准偏差(RSD)(n=6)为3.5%～11.3%;在鸡肝中的平均回收率为70.8%～92.7%, RSD(n=6)为5.3%～12.6%。该方法选择性好,抗干扰能力强,可作为鸡肉和鸡肝中抗病毒药物残留检测的确证方法。     

超高效液相色谱-电喷雾串联质谱法同时测定地表水中28种皮质激素

建立了同时测定地表水中28种皮质激素的超高效液相色谱-电喷雾串联质谱（UHPLC-ESI-MS/MS）的分析方法。水样经HLB柱固相萃取、C₈反相色谱柱分离,在动态多反应监测（DMRM）模式下采用电喷雾离子化正、负离子模式（ESI±）进行信号采集与测定,内标法定量。结果发现,28种皮质激素在1.0~100 μg/L范围内具有良好的线性关系（R²>0.99）,方法检出限为0.21~0.48 ng/L,方法定量限为0.32~0.72 ng/L。在5.0、10、50 ng/L的基质加标水平下,28种目标物的平均回收率为68.8%~108.7%,相对标准偏差为0.1%~8.1%。该方法灵敏、准确、可靠,将广泛应用于环境中糖/盐皮质激素的痕量监测及其行为、风险研究。     

Rapid and sensitive determination of fatty acids in edible oil by liquid chromatography-electrospray ionization tandem mass spectrometry

A sensitive and robust on-line LC/MS method was developed for quantitative determination of linoleic acid,docosahexaenoic acid and docosanoic acid from edible oil samples.The oil samples were dissolved in chloroform-isopropyl alcohol(20:80,v:v)solution and the three fatty acids were separated by HPLC with a C4 column using 10 mmol/L ammonium acetate-isopropyl alcohol-acetonitrile(20:40:40,v:v:v)mobile phase in isocratic elution.Electrospray ionization mass spectrometry with the selected ion recording monitoring was used to detect and quantify the fatty acid.The calibration curves were linear in the range of 10.00–5000 pg/mL for linoleic acid and docosanoic acid,and 1.000–500.0 pg/mL for docosahexaenoic acid.The limit of detection was 2.0 pg/mL for linoleic acid,3.0 pg/mL for docosanoic acid,and 0.20 pg/mL for docosahexaenoic acid.The results showed that the method described in this paper could be utilized for rapid determination of three fatty acids at picogram levels in edible oils.     

Simultaneous determination of phoxim and its photo-transformation metabolite residues in eggs using liquid chromatography coupled with electrospray ionization tandem mass spectrometry

The principal objective of this study was to develop an appropriate, sensitive, and selective method for the simultaneous quantitative determination of phoxim and its photo-transformation product, O,O-diethyl α-cyanobenzylideneamino-thiophosphonate (DCTP) in both chicken and quail eggs. Eggs (1 g) were blended with anhydrous magnesium sulfate (1 g) for sample pretreatment and extracted with acetonitrile. The extracts were then further purified with SPE silica gel tubes deactivated with trimethylamine. Residues were analyzed via a reversed phase-liquid chromatography-tandem mass spectrometry (RP-LC-MS/MS) in positive-ion electrospray ionization (ESI) mode. Tebufenozide was utilized as an internal standard for the quantification of phoxim and its metabolite residues. The identification and quantification of analytes were based on ion transitions monitored by multiple reaction monitoring (MRM). LC-MS/MS analysis was performed from 0.02 to 1 mg kg⁻¹ and correlation coefficients (r²) ranging from 0.998 to 0.999 were obtained for both analytes in blank egg extracts. The relative standard deviations (RSDs) of intra- and inter-day variations ranged from 2.1% to 6.7% and from 2.8% to 6.4% for phoxim and DCTP in chicken and quail eggs. At all levels of fortification (0.02, 0.05, and 0.125 mg kg⁻¹), the recoveries fell within a range of 81.3% to 93.6% for phoxim and 83.3% to 90.1% for DCTP. The matrix effect was <2%, due to the partial dilution of the sample. Decision limits (CCα) and detection capabilities (CCβ) were in the range of 0.0005-0.0044 and 0.0054-0.0224 mg kg⁻¹, respectively. The method was evaluated further by analyzing real samples purchased from markets. All chicken and quail egg samples were free from residues of the target compounds.     

Quantification of zolpidem in human plasma by liquid chromatography-electrospray ionization tandem mass spectrometry

A simple and robust method for quantification of zolpidem in human plasma has been established using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI MS/MS). Es-citalopram was used as an internal standard. Zolpidem and internal standard in plasma sample were extracted using solid-phase extraction cartridges (Oasis HLB, 1 cm3/30 mg). The samples were injected into a C8 reversed-phase column and the mobile phase used was acetonitrile-ammonium acetate (pH 4.6; 10 mm) (80:20, v/v) at a flow rate of 0.7 mL/min. Using MS/MS in the selected reaction-monitoring (SRM) mode, zolpidem and Es-citalopram were detected without any interference from human plasma matrix. Zolpidem produced a protonated precursor ion ([M+H]+) at m/z 308.1 and a corresponding product ion at m/z 235.1. The internal standard produced a protonated precursor ion ([M+H]+) at m/z 325.1 and a corresponding product ion at m/z 262.1. Detection of zolpidem in human plasma by the LC-ESI MS/MS method was accurate and precise with a quantification limit of 2.5 ng/mL. The proposed method was validated in the linear range 2.5-300 ng/mL. Reproducibility, recovery and stability of the method were evaluated. The method has been successfully applied to bioequivalence studies of zolpidem.     

Large volume injection for the direct analysis of ionophores and avermectins in surface water by liquid chromatography-electrospray ionization tandem mass spectrometry

A simple method for the direct determination of residues of ionophore antibiotics and avermectin antiparasitics in surface water is reported. Using a large volume injector, a mixture of methanol and surface water is injected into an analytical liquid chromatography (LC) column and subsequently screened for residues of these veterinary pharmaceuticals using electrospray ionization tandem mass spectrometry. On-line sample enrichment and chromatographic separation are achieved using a single, short (20 mm) octadecylsilane LC column. The method permits the detection of four ionophores and two avermectins in surface water samples at low ng L⁻¹ concentrations. Minimal matrix effects were observed for a variety of surface water samples which permitted the use of reagent-based standards for quantitation.     

高效液相色谱-电喷雾串联质谱法同时测定鸡肉中残留的磺胺类和氟喹诺酮类兽药

建立了一种同时测定鸡肉中两类共10种兽药(3种磺胺和7种氟喹诺酮类药物)残留量的高效液相色谱-电喷雾串联质谱方法(HPLC -ESI-MS2)。样品经2%醋酸-乙腈提取,正己烷脱脂,过ENVI-18固相萃取柱净化,经氮气吹干后,残余物用流动相定容到1 mL。以乙腈和 0.05%甲酸溶液作为流动相,采用梯度洗脱程序进行液相色谱分离,用质谱检测器进行定性和定量分析,并对10种药物的二级质谱碎裂方 式进行分析。10种药物在0.02～2.0 mg/L范围内线性良好,相关系数均大于0.9988。检出限(LOD)为1.10～6.85 μg/kg,定量限(LOQ) 为3.68～22.85 μg/kg,样品的平均加标回收率为68.9%～102.6%,相对标准偏差均小于8.6%(n=3)。实验结果表明,该方法灵敏度高,重 现性好,确证能力强,分析时间短,可满足动物源性食品中磺胺和氟喹诺酮类药物的残留分析。     

液相色谱-电喷雾离子阱串联质谱同时分析烟草中的20种游离氨基酸

建立了液相色谱-电喷雾离子阱串联质谱(LC-ESI-IT-MS/MS)同时分析烟草中20种游离氨基酸的方法。烟草样品经萃取后过滤直接进样,无需进行衍生和固相萃取等其他前处理步骤。液相色谱采用HyPURITY C18反相色谱柱(200 mm×2.1 mm, 5 μm),采用1%(体积分数,下同)乙腈水溶液(含0.1%九氟戊酸)和90%乙腈水溶液(含0.1%九氟戊酸)为流动相进行梯度洗脱。结果表明,20种氨基酸的检出限(LOD)为0.01～0.05 μmol/L (S/N=3),线性相关系数均大于0.9977,峰面积测定的相对标准偏差(RSD)为0.78%～4.93%。该方法分析效率、灵敏度和选择性高,已成功应用于多种烟草样品中氨基酸的分析测定。