Determination of thyreostats in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry

Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.

Detection of 36 antibiotics in coastal waters using high performance liquid chromatography-tandem mass spectrometry

Among pharmaceuticals and personal care products released into the aquatic environment, antibiotics are of particular concern, because of their ubiquity and health effects. Although scientists have recently paid more attention to the threat of antibiotics to coastal ecosystems, researchers have often focused on relatively few antibiotics, because of the absence of suitable analytical methods. We have therefore developed a method for the rapid detection of 36 antibiotic residues in coastal waters, including tetracyclines （TCs）, sulfanilamides （SAs）, and quinolones （QLs）. The method consists of solid-phase extraction （SPE） and liquid chromatography-tandem mass spectrometry （LC-MS/MS） analysis, using electrospray ionization （ESI） in positive mode. The SPE was performed with Oasis HLB and Oasis MCX cartridges. Chromatographic separation on a Cr8 column was achieved using a binary eluent containing methanol and water with 0.1% formic acid. Typical recoveries of the analytes ranged from 67.4% to 109.3% at a fortification level of 100 ng/L. The precision of the method, calculated as relative standard deviation （RSD）, was below 14.6% for all the compounds. The limits of detection （LODs） varied from 0.45 pg to 7.97 pg. The method was applied to detemaine the target analytes in coastal waters of the Yellow Sea in Liaoning, China. Among the tested antibiotics, 31 were found in coastal ＇waters, with their concentrations between the LOD and 212.5 ng/L. These data indicate that this method is valid for analysis of antibiotics in coastal waters. The study first reports such a large number of antibiotics along the Yellow Sea coast of Liaoning, and should facilitate future comprehensive evaluation of antibiotics in coastal ecosystems

Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry

To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry （UPLC/MS/MS）. The water samples were extracted and condensed with solid-phase extraction （SPE） using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.

Determination of Steroid Hormone Residues in Fish Tissues Using Gel Permeation Chromatography and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.

Chemical Components of Achyranthes bidentata Leaves by Ultra High Performance Liquid Chromatography-Mass Spectrometry

[Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical components of A. bidentata leaves were rapidly analyzed using the ultra high performance liquid chromatography-time of flight-high resolution mass spectrometry (UHPLC-TOF-MS).[Results] Thirty eight chemical compounds were identified in samples of A. bidentata leaves collected from Wen County of Henan Province, in which seven chemical compounds had the relative content higher than 5%, linoleic acid reached 25.7% and inokosterone A reached 13.8%.[Conclusions] A. bidentata leaves contain many kinds of chemical compounds. This study is expected to provide a certain basis for further extraction of linoleic acid and inokosterone A.

Simultaneous Determination of Ultraviolet Absorbers and Antibacterial Agents in Textiles by Ultra-High Performance Liquid Chromatography/Orbitrap High Resolution Mass Spectrometry

This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile samples in methanol, the solutions were analyzed by ultra-high performance liquid chromotagraphy/orbitrap high resolution mass spectrometry (UPLC/Orbitrap HRMS). It showed that a good chromatographic separation for these target compounds was achieved by a Hypersil GOLD column (100 mm × 2.1 mm × 1.9 μm) with a gradient elution of methanol and 0.1% aqueous formic acid solution (containing 0.5 mmol/L ammonium acetate). Triclosan and 4-chloro-3,5-dimethyl phenol (PCMX) were detected by the orbitrap HRMS in an electrospray ionization (ESI) negative mode while the other twelve target compounds were detected by orbitrap HRMS in ESI positive mode. Full scan experiment was performed over the range from m/z 100 to m/z 500. These target compounds were routinely detected with mass accuracy below 2 × 10-6 (2 ppm) at the optimized conditions. The results showed that the limits of detection (LODs) were in the range from 0.1 to 0.3 μg/kg. The blank samples were spiked at three levels and their average recoveries varied from 80.5% to 96.3% while the relative standard deviation (RSD) changed from 3.2% to 9.9%. The present method was also applied for the determination of those ultraviolet absorbers and antibacterial agents in the commercial textiles.

Rapid Determination of Three Kinds of Microcystins in Environmental Water Samples by Disk SPE-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A method of rapidly detecting three kinds of microcystins( MCs) in environmental water samples by using disk SPE- ultra high performance liquid chromatography- tandem mass spectrometry( UPLC- MS / MS) was established. Firstly,environmental water samples were extracted by disk SPE column( C_(18)),and three kinds of MCs were separated by Waters BEH C_(18) chromatographic column with acetonitrile- 0. 2% formic acid solution as the mobile phase. After the gradient elution separation,the external standard method was used for quantitative and qualitative analysis under MRM of UPLC- MS / MS. The results showed that the three kinds of MCs in the range of 0. 05- 10 μg / L showed good linear relation,and the correlation coefficients were higher than 0. 999 4,while the method detection limit was 0. 04 ng / L. Under 0. 1,1,and 5 μg / L standard addition for the same environmental sample,the average recovery was 82. 8%- 108. 8%,and the relative standard deviation of determination results was2. 1%- 10. 1%( n = 6). This method is rapid,sensitive and accurate,so it can be effectively applied in the monitoring of MCs in environmental water samples.

Simultaneous Determination of 14 β-Receptor Agonists Residues in Mutton by High Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS)

[Objectives]A high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method was established for the determination of 14β-receptor agonist residues in mutton.[Methods]Samples were hydrolyzed byβ-glucuronidase and extracted with 5%acetic acid-acetonitrile(1:99,V/V)solution.An Eclipse plus C 18 column was used for separation,and the MRM mode was used for qualitative analysis,and the external standard method was used for quantitative analysis of matrix standard solutions.[Results]Under the optimal conditions,the retention time of the 14 kinds ofβ-receptor agonists ranged from 1.0 to 9.5 min.When the mass concentration was in the range of 0.05-0.50μg/ml,the linear relationship ofβ-receptor agonists was good,with correlation coefficients(r)≥0.9992.The detection limits of the method were in the range of 0.04-0.87μg/kg,and the quantitative limits were in the range of 0.35-1.86μg/kg.The average recovery values were in the range of 82.8%-108.9%,with RSDs(n=6)in the range of 1.9%-6.7%.[Conclusions]The method is simple,sensitive,reproducible,accurate,and can be used for simultaneous determination of the 14 kinds ofβ-receptor agonist residues in mutton.

Determination of okadaic acid related toxins from shellfish (<i>sinonovacula constricta</i>) by high performance liquid chromatography tandem mass spectrometry

Consumption of shellfish contaminated with algal toxins produced by marine dinoflagellates can lead to diarrhetic shellfish poisoning (DSP). It was therefore essential that there are analytical techniques to identify and quantify DSP toxins in shellfish. This new methodology could facilitate DSP monitoring and create a means of rapidly responding to incidents threatening public health. In the last years there were different analytical methods for DSP, such as mouse bioassay and LC-FLD. With the development of instrument, Liquid chromatography-mass spectrometry was substituted for other analytical methods with its good sensitivity and selectivity and without derivatization for the determination of DSP. In this report, a high performance liquid chromatogra-phytandem mass spectrometric(HPLC-MS/MS)method was developed for the simultaneous determination of okadaic acid (OA) and dinophysistoxins(DTX1) in Sinonovacula constricta. Optimization of pretreatment experiment was carried out to maximize recoveries and the effectiveness. The analytes were determined under multi-reactions monitoring (MRM) scan type with tandem mass analyzer using negative ion electrospray ionization (-ESI) mode .Finally, the detection and identification of OA and DTX-1 were based upon their retention times (RT) and the fragmentation patterns of their mass spectra. The method of LOQ for the two poisons was 0.02 mg·kg-1.The real sample test showed that this method could be used for sensitive, fast, and accurate determination of the two diarrheic shellfish poisons in shellfish.

Development of a Rapid and Simultaneous Detection Method for Buprenorphine, Norbuprenorphine and Naloxone in Human Plasma Using Ultra-high Performance Liquid Chromatography- tandem Mass Spectrometer with Solid-phase Extraction

A simultaneous method was successfully established and validated for the separation and determination of bu- prenorphine （BP）, its primary metabolite, nor-buprenorphine （NBP） and a proposed co-formulate, naloxone （NLX） in human plasma. The method used buprenorphine-d4 （BP-D4）, nor-buprenorphine-d3 （NBP-D3）, naltrexone （NTX） as internal standards （ISs）. 100 μL of plasma sample fortified with the ISs was cleaned up by solid-phase extraction （SPE）, and was then separated on a Waters AcquityTM BEH C18 column with gradient elution using methanol and water （containing 0.2% formic） at a flow rate of 0.25 mL·min^-1. The mass spectrometer was used for detection and was operated in the positive electrospray ionization with multiple reaction monitoring （MRM） mode. The three compounds were effectively separated in 5 min. The linear ranges of the compounds were 0.1--25, 0.25--25 and 0.05--25 ng·mL^-1 for BP, NBP and NLX, respectively, with r≥0.9935. The method had high sensitivity （the lim- its of detection were 0.02, 0.1 and 0.01 ng.mL-1 for BP, NBP and NLX, respectively） and high recoveries （≥97.6%）. The result was shown to be linear and satisfactorily met current acceptance criteria for validation of bio- analytical method： intra and inter assay precisions within the required limits of ≤25% RSD. The LOQs fulfilled the LOQ requirements： precision≤25% RSD, and was fully validated according to the State Food and Drug Administration （SFDA） regulations. The results demonstrated that ultra-high performance liquid chromatography- tandem mass spectrometer （UPLC-MS/MS） with SPE was a powerful detection tool and contributed to pharmaceutical analysis in biological matrices.

Determination of chlorpromazine in porcine muscle using high performance liquid chromatography-tandem mass spectrometry

A rapid and accurate high performance liquid chromatography tandem mass spectrometry（HPLS-MS） method was established for quantification of chlorpromazine in pork. The porcine samples were pretreated with acetonitrile to precipitate proteins and followed by extraction with tert--butyl methyl ether（TBME）. The separation was performed on a 5 μm Agilent XDB--C18 column with gradient elution. The mobile phase A was 0.01 mol/L ammonium formate in water and mobile phase B was acetonitrile. The flow rate was at 0.8 mL/min. Quantification was performed on a triple-quadrupole tandem mass spectrometer using the multiple selected reaction monitoring（MRM） mode. Transition of m/z ＋319.1 to 58.1 was used for the quantification of chlorpromazine. The method was validated at the concentration range of 0.4040 μg/kg to 8.080 μg/kg for chlorpromazine with correlation coefficient of 0.9999. The spiked recoveries were more than 80.0% and the limit of detection（LOD） was 0.052 μg/kg. The developed method, which offers advantages of convenience, rapid, specificity and higher sensitivity, can be used for determination of chlorpromazine hydrochloride in porcine muscles.

基于网络药理学探究双孢菇的肝脏保护作用

为研究双孢菇乙醇提取物(Agaricus bisporus ethanol extract,ABEE)保肝活性的物质基础及其作用机制,采用超高效液相色谱-串联质谱(ultra-high performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)技术对ABEE的成分进行分析鉴定,通过网络药理学结合CCl4致小鼠急性肝损伤动物模型对其活性物质及作用机制进行分析。UPLC-MS/MS分析鉴定化合物75个,其中网络药理学预测与肝损伤活性相关化合物15个,作用靶点11个。动物实验结果显示,ABEE能够显著改善由CCl4导致的小鼠急性肝损伤,与模型组相比,高剂量组(1000 mg/kg)肝功能指标谷草转氨酶、谷丙转氨酶、碱性磷酸酶得到了显著恢复(P<0.001),同时小鼠体内抗氧化能力得到显著提高,与模型组相比,超氧化物歧化酶、谷胱甘肽过氧化物酶活力显著提高(P<0.001),丙二醛含量显著下降(P<0.01)。采用实时荧光定量聚合酶链式反应和Western blot技术对相关基因的mRNA和蛋白表达水平进行检测,结果显示,与模型组相比,高剂量组Bcl-2表达显著上升(P<0.001),MYC、NF-κB1、RELA、MMP9表达显著降低(P<0.01),证实了预测结果。因此,ABEE可能是通过水杨酸、棕榈酸、α-亚麻酸、白杨素调节Bcl-2、MYC、NF-κB1、RELA的表达及其所在的化学致癌-受体激活等信号通路,从而发挥肝脏保护作用。本研究结果表明ABEE可能是通过多成分、多靶点、多通路抑制细胞凋亡、癌变,抑制自由基脂质过氧化来发挥肝脏保护作用。

基于肠道菌群和广泛靶向代谢组学的山柰酚抗骨质疏松的作用机制

背景:山柰酚具有抗骨质疏松的作用,但山柰酚通过调控肠道菌群、代谢物防治骨质疏松的作用机制尚不明确。目的:基于肠道菌群和广泛靶向代谢组学探究山柰酚抗骨质疏松的可能作用机制。方法:将雌性Sprague-Dawley大鼠18只随机分为假手术组、模型组和山柰酚组,每组6只,后2组切除双侧卵巢制备骨质疏松大鼠模型。造模后8周,假手术组和模型组采用蒸馏水灌胃,山柰酚组采用40 mg/kg山柰酚灌胃,各组均连续给药12周。取大鼠粪便进行16SrDNA扩增子测序,观察肠道菌群结构的变化;采用超高效液相色谱-串联质谱技术、自主开发的数据库和多元统计分析的方法进行血清样本广泛靶向代谢组学检测。结果与结论:①连续干预12周后,16SrDNA扩增子测序结果显示,与假手术组相比,模型组肠道菌群丰度增加;与模型组相比,山柰酚组上调Latilactobacillus菌属(P=0.021)丰度,下调泛菌属(Pantoea)(P=0.034)、肠杆菌属(Enterorhabdus)(P=0.000)、Monoglobus菌属(P=0.024)、丁酸单胞菌属(Butyricimonas)(P=0.034)、Rothi属(P=0.043)、梭杆菌属(Clostridia)(P=0.004)等菌属丰度。②连续干预12周后,血清样本广泛靶向代谢组学检测结果显示,假手术组与模型组、模型组与山柰酚组之间分别鉴定出120和79种代谢物,3组间共有17种交集差异代谢物,包括乌头酸、巴比妥酸、L-高瓜氨酸、3,4,5-三甲氧基肉桂酸、L-3-苯基乳酸、环(脯氨酸-脯氨酸)、L-苯丙氨酸-L-丝氨酸、脯氨酸-异亮氨酸、L-冬胺基乙酸-L-苯丙胺基乙酸、苯丙氨酸-天冬氨酸等。大部分属于氨基酸及其代谢物、甘油磷脂类和脂肪酰类。差异代谢物涉及的KEGG通路主要富集在D-氨基酸代谢、组氨酸代谢、丙酸代谢、赖氨酸降解、脂肪酸代谢、鞘脂代谢等。③连续干预12周后,联合分析发现,肠杆菌属(Enterorhabdus)、Latilactobacillus属、Rothia属和瘤胃球菌属(Ruminococcus)等与血清差异代谢物密切相关。④山柰酚可能通过调节肠道菌群的丰度、多样性及结构,调控氨基酸及其代谢物的代谢、脂肪酸代谢等发挥抗骨质疏松的作用。

固相萃取-超高效液相色谱-串联质谱法测定蜂蜜中39种植物源性毒素

为有效评估蜂蜜中可能残留多种植物源性毒素的食品安全风险,建立和验证固相萃取-超高效液相色谱-串联质谱测定蜂蜜中39种植物源性毒素的检测方法。试样经0.1%甲酸水提取,HLB小柱净化,多反应监测模式检测,基质匹配外标法定量。本方法中39种植物源性毒素在各自浓度范围内线性关系良好,平均回收率介于78.7%~112.8%,相对标准偏差介于1.6%~15.2%(n=6)。该方法具有操作简单、检测通量大、灵敏度高等特点,能够满足蜂蜜中该类毒素监测的应用需求。在实际36批次样品的检测过程中,部分样品分别检出了不同含量的吡咯里西啶生物碱和闹羊花毒素III,证明蜂蜜中确具有残留该类植物毒素的风险。

Mitochondrial metabolomic profiling for elucidating the alleviating potential of Polygonatum kingianum against high-fat diet-induced nonalcoholic fatty liver disease

BACKGROUND Developing mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represent attractive strategies for therapy of nonalcoholic fatty liver disease(NAFLD).Polygonatum kingianum(PK)has been traditionally used in China as a medicinal and nutritional ingredient for centuries and can alleviate high-fat diet(HFD)-induced NAFLD by promoting mitochondrial functions.To date,the underlying molecular mechanism of PK for treating mitochondrial dysfunctions and thus alleviating NAFLD remains unclear.AIM To identify the molecular mechanism behind the mitochondrial regulatory action of PK against HFD-induced NAFLD in rats.METHODS NAFLD model was induced in rats with HFD.The rats were intragastrically administered PK(4 g/kg per day)for 14 wk.Metabolites in hepatic mitochondrial samples were profiled through ultra-high performance liquid chromatography/mass spectrometry followed by multivariate statistical analysis to find the potential biomarkers and metabolic pathways.RESULTS PK significantly restored the metabolites’levels in the mitochondrial samples.Ten potential biomarkers were identified in the analyzed samples.These biomarkers are involved in riboflavin metabolism.CONCLUSION PK can alleviate HFD-induced NAFLD by regulating the riboflavin metabolism and further improving the mitochondrial functions.Thus,PK is a promising mitochondrial regulator/nutrient for alleviating NAFLD-associated diseases.

改良QuEChERS技术结合超高效液相色谱-串联质谱法测定水产品中扑草净及其代谢物残留

采用改良QuEChERS技术作为前处理方法,建立了水产品中扑草净及其代谢物残留的超高效液相色谱-串联质谱分析方法。样品用乙腈提取,经增强型脂质去除吸附剂与Cleanert LipoNo组合净化,采用选择反应监测正离子模式测定,内标法定量。结果表明:扑草净及其代谢物在1.0~500 ng/mL质量浓度范围内线性关系良好,确定系数R2大于0.992,方法检出限和定量限分别低至0.20μg/kg和0.50μg/kg,在草鱼、克氏原螯虾和中华绒螯蟹等基质的加标实验中呈现良好的准确度与精密度,平均加标回收率和相对标准偏差分别为74.4%~113.7%和3.17%~11.47%。经内标法校正,5种扑草净及其代谢物在不同水产品中的基质效应不明显。方法实现了水产品中扑草净及其代谢物的识别与定量分析,并通过检测药浴扑草净的克氏原螯虾阳性样品验证了方法的适用性。

分散固相萃取净化-超高效液相色谱-串联质谱法测定蜂蜜中双甲脒、杀虫脒及其代谢物

该研究建立了分散固相萃取-超高效液相色谱-串联质谱(dispersive solid phase extraction-ultra-performance liquid chromatography,UPLC-MS-MS)检测蜂蜜中双甲脒、杀虫脒及其代谢物残留的分析方法。蜂蜜样品2 g加入10 mL水溶液充分混匀,经1%(体积分数)氨化乙腈超声辅助提取后离心,利用N-丙基乙二胺、C18、氨基键合硅胶混合材料进行分散固相萃取净化,采用ACQUITY UPLC BEH C18(2.1 mm×50 mm,1.7μm)色谱柱分离,以甲醇和0.1%(体积分数)甲酸水溶液为流动相进行梯度洗脱,多反应监测模式正离子扫描分析。6种农药及其代谢物平均回收率为84.1%~113.8%,相对标准偏差为0.9%~6.0%,检出限为0.2~0.8μg/kg,定量限为0.7~2.5μg/kg。实验结果表明该方法快速简便、灵敏度高,适用于蜂蜜中双甲脒、杀虫脒及其代谢物残留同时分析。

超高效液相色谱-串联质谱法测定水体和底泥中的阿维菌素和伊维菌素

为建立超高效液相色谱-串联质谱法(UHPLC-MS/MS)同时测定水产养殖环境(水体及底泥)中阿维菌素和伊维菌素的检测方法。先采用HLB固相萃取柱富集和净化水样,采用PSA和C18吸附剂净化底泥样品;样品中的目标物采用Phenomenex Kinetex C18色谱柱分离,以5 mmol/L乙酸铵水溶液和乙腈作为流动相进行梯度洗脱,在电喷雾离子源(ESI)、正离子扫描和多反应监测(MRM)模式下进行测定,外标法定量。在最优实验条件下,阿维菌素和伊维菌素在7.5 min内完成色谱分离分析,目标物在1~100μg·L^(-1)范围内线性关系良好,相关系数均大于0.995。空白水样在0.05,0.50,2.5和5.0μg·L^(-1)共4个添加水平下的回收率为71.6%~88.2%,相对标准偏差(RSD,n=6)在1.51%~8.81%,方法检出限(LOD)为0.02μg·L^(-1),方法定量限(LOQ)为0.05μg·L^(-1);空白底泥在1.0,10.0,50.0和100.0 ng·g^(-1)共4个添加水平下的回收率为75.3%~96.4%,RSD值(n=6)为3.45%~8.99%,LOD值为0.3 ng·g^(-1),LOQ值为1.0 ng·g^(-1)。该方法灵敏度高,重现性好,操作快速简便,适用于水产养殖环境(水体和底泥)中阿维菌素和伊维菌素的分析检测。

超高效液相色谱-四极杆-飞行时间高分辨质谱用于化妆品中15种前列腺素类似物的快速筛查和测定

建立了超高效液相色谱-四极杆-飞行时间高分辨质谱(UPLC-Q-TOF MS)快速筛查和测定化妆品中15种前列腺素类似物的方法。样品以饱和氯化钠作为分散剂(蜡质类样品以四氢呋喃分散),经乙腈提取,离心取上清液过滤后,采用Poroshell 120 EC-C_(18)柱(150 mm×3.0 mm,2.7μm)分离,以5 mmol/L甲酸铵(含0.1%甲酸)-乙腈为流动相梯度洗脱。在ESI正离子模式下,采用Targeted MS/MS模式采集15种前列腺素类似物的质谱信息,构建筛查数据库进行快速筛查,确证后的目标物通过外标法定量。结果表明,15种前列腺素类似物的线性关系良好,相关系数(r^(2))均大于0.99;检出限为0.3~17.6μg/g,定量下限为1.1~58.8μg/g。在低、中、高3个加标水平下,水剂、膏霜、乳类、粉类、凝胶5类化妆品基质的回收率为70.1%~134%,相对标准偏差不大于7.5%。该方法简单高效、准确度好,可用于化妆品中前列腺素类似物的定性确证和定量分析,为化妆品风险识别提供技术支撑。

荔枝中20种登记农药残留分析方法研究

为解决荔枝中20种登记农药多残留的同时快速检测问题,建立并优化基于超高效液相色谱-串联质谱(UPLC-MS/MS)同时检测荔枝中7种杀虫剂和13种杀菌剂的分析方法。荔枝全果样品经80%乙腈水溶液提取后,用石墨化碳黑(GCB)净化,流动相为乙腈和水,梯度洗脱,采用Extend C18色谱柱进行分离。电喷雾正负离子交替模式采集,多反应监测(MRM),外标法定量。20种供试农药的质量浓度与其对应的峰面积之间呈现良好线性关系,相关系数均大于0.9990;20种农药在荔枝基质中的平均回收率为71%~106%,相对标准偏差(RSD)在0.9%~9.8%之间,满足残留分析的要求。该方法简便、高效,可用于荔枝样品中20种农药残留的快速检测。