超高效液相色谱-串联四极杆质谱法测定水产品中氯霉素残留量

建立超高效液相色谱-串联四极杆质谱法测定水产品中氯霉素残留量的方法。样品均质后经乙酸乙酯提取,正己烷脱脂(或用固相萃取柱净化),超高效液相色谱分离,串联四级杆质谱检测,同位素内标法定量。方法在0.05～1.0μg/kg的添加范围内的平均回收率为84.9%～103.3%,相对标准偏差为3.2%～5.2%,定量检测限为0.02μg/kg。方法适用于各种水产品基质的氯霉素残留检测。     

乳及乳制品中黄曲霉毒素B_1、M_1测定方法改进

建立了一种检测乳及乳制品中黄曲霉毒素B1、M1的高效液相色谱-荧光检测(HPLC-FD)方法。样品经60%乙腈溶液提取,自制固相萃取柱净化,流出液经正己烷、三氟乙酸衍生后荧光检测器检测。考察了填料、柱容量、取样量、提取溶液和流速等对检测的影响,优化了实验条件。结果表明,黄曲霉毒素B1、M1的检测线性范围为0.40~100μg/L,线性系数为0.9991~0.9998,方法检出限为0.050μg/kg。对样品进行0.40、1.0和15μg/L 3种浓度水平的加标回收实验,回收率为53%~105%,相对标准偏差为2.6%~5.1%。该方法操作简单、灵敏度高、准确度好,可用于乳及乳制品中黄曲霉毒素B1、M1的测定。     

高效液相色谱-串联质谱法测定乳及乳制品中大观霉素药物残留

建立了检测乳及乳制品中大观霉素药物残留量的高效液相色谱-串联质谱方法。样品直接采用0.1 mol/L乙二胺四乙酸二钠水溶液提取。挥发性离子对试剂七氟丁酸水溶液和甲醇作为流动相,增加了大观霉素的保留时间。本方法对液态奶、奶粉、酸奶、奶酪、奶油中大观霉素的测定低限均为100μg/kg。方法的线性范围为5～500 ng/mL(相关系数r0.991),回收率为75.6%～99.3%,相对标准偏差小于7.5%,能够满足乳及乳制品中大观霉素残留量的快速检测。     

超高效液相色谱-串联质谱法测定鱼粉中孔雀石绿

建立了鱼粉中孔雀石绿及其代谢物隐色孔雀石绿残留量的超高效液相色谱-串联质谱仪(UPLC-MS-MS)测定法。样品经乙腈提取,中性Al2O3固相小柱净化,超高效液相色谱C18柱分离,电喷雾正离子多反应模式(MRM)检测,内标法定量。方法的定量限为1.00μg/kg,线性范围为0.25～20.0μg/L。在1.00～20.0μg/kg的加标量下,孔雀石绿平均回收率范围为85.3%～104.4%,隐色孔雀石绿平均回收率范围为85.7%～101.4%,相对标准偏差均小于15%。方法适用于鱼粉样品中孔雀石绿残留的快速检测。     

同位素内标-高效液相色谱串联质谱法测定乳及乳制品中13种β-受体激动剂类药物残留

建立了乳及乳制品中13种β-受体激动剂类药物多残留的同位素内标-高效液相色谱串联质谱分析方法。样品经三氯乙酸沉淀蛋白,提取液经SupelcleanLC-SCX固相萃取柱净化后,用HPLC-MS/MS进行测定。采用AgilentEclipse Plus C18色谱柱(2.1×150 mm,3.5μm),0.1%甲酸水-乙腈流动相进行梯度洗脱,用电喷雾离子源正离子多反应监测(MRM)模式进行MS/MS检测。其中克伦特罗在0.05～5.0μg/kg线性范围内,其余12种分析物在0.25～10μg/kg线性范围内具有较好的线性关系,相关系数r>0.9988。方法检出限(LOD)为0.02～0.17μg/kg,定量限(LOQ)为0.05～0.48μg/kg。空白样品添加回收率为83.2%～102.6%,相对标准偏差为5.0%～13%。     

超高效液相色谱-串联四极杆质谱法同时检测乳制品中β-内酰胺酶抑制剂克拉维酸钾、他唑巴坦和舒巴坦的残留量

建立了乳制品中克拉维酸钾、他唑巴坦和舒巴坦的提取和固相萃取净化法。样品采用水溶后用丙酮沉淀蛋白,在弱酸性条件下用PWAX,60 mg/3 mL固相萃取小柱富集、净化,0.05%氨水/甲醇溶液洗脱后采用超高效液相色谱-串联四极杆质谱(UPLC-MS/MS)检测,分析柱为Waters BEH C18,1.7μm,2.1×100 mm;流动相为0.1%甲酸-乙腈。该方法对克拉维酸钾、他唑巴坦和舒巴坦的最低检测质量浓度为0.01,0.003和0.009μg/mL;对纯牛奶、酸奶和奶粉的回收率在81.2%～103.2%之间,相对标准偏差RSD在1.3%～4.8%之间(n=6);在0.05～5μg/mL浓度范围内均呈良好的线性关系,线性回归系数r>0.999。方法适用于乳制品中β-内酰胺酶抑制剂的测定。     

固相萃取-高效液相色谱法测定乳及乳制品中土霉素、四环素和金霉素残留

建立了固相萃取-高效液相色谱同时测定乳及乳制品中土霉素、四环素和金霉素的方法。样品经pH 4.0的Na2EDTA-mcllvaine缓冲溶液漩涡超声提取后,采用Oasis HLB固相萃取(SPE)小柱净化,洗脱液用N2吹至近干后用流动相溶解并定容,过PTFE滤膜后在Shiseido MG C18色谱柱上,以V(乙腈):V(10 mmol/L草酸)=27∶73的溶液为流动相进行分离,检测波长为360 nm。在最优的色谱条件下,各目标化合物的加标回收率为83.0%~109.2%,相对标准偏差在2.8%~6.1%之间。3种抗生素含量在0.10~20.0 mg/L范围内线性关系良好,相关系数≥0.999,乳及乳制品中土霉素、四环素和金霉素的检出限分别为10,10和20μg/kg。     

乳制品中那他霉素的超高效液相色谱-串联质谱法快速测定

建立了超高效液相色谱-电喷雾串联质谱(UPLC-MS/MS)快速检测乳制品中那他霉素的方法。样品用甲醇提取,以甲醇-水为流动相经反相色谱柱分离后,采用多反应监测(MRM)负离子模式检测,定性离子对为m/z663.6/421.1和m/z663.6/439.1,其中m/z663.6/421.1用于外标法定量。空白样品及其加标实验结果表明:特征离子相对强度比值稳定,无基质干扰,结合保留时间可实现准确的定性定量;方法定量下限为50.0μg/kg;乳制品加标量为50~500μg/kg时,平均回收率为80%~91%,相对标准偏差(n=6)为2.7%~5.2%。方法简单、灵敏、稳定,可满足乳制品中那他霉素的快速检测与确证需要。     

超高效液相色谱-串联质谱法同时测定尿液与血清中23种双酚类化合物

建立了基于吡啶-3-磺酰氯衍生和超高效液相色谱-串联质谱(UPLC-MS/MS)检测尿液和血清中23种双酚类化合物(BPs)的方法。尿液样品采用乙酸乙酯提取;血清样品采用乙腈提取,上清液经PRiME HLB柱净化。提取液经吡啶-3-磺酰氯衍生后,以乙腈和0.1%甲酸水溶液为流动相,采用ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm,1.7μm)色谱柱进行分离。质谱离子源为电喷雾电离源,正离子模式检测。23种目标物在0.005～100μg/L范围内线性关系良好,检出限为0.002～0.030μg/L,定量下限为0.005～0.100μg/L,回收率为76.6%～122%,相对标准偏差(RSD)为0.60%～14%。使用建立的方法分别对20份尿液和20份血清样品进行了检测。该方法样品用量少,灵敏度高,可以满足尿液和血清样品中23种BPs的同时测定要求。     

固相萃取/超高效液相色谱-串联质谱法测定乳与乳制品中万古霉素、去甲万古霉素残留

建立了固相萃取/超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定乳和乳制品中万古霉素、去甲万古霉素残留量的分析方法。样品经乙腈-水溶液提取,三氯乙酸沉淀蛋白,二氯甲烷去除脂肪等杂质,Strata-X-C SPE小柱净化,以乙腈和0.1%甲酸水溶液作为流动相进行梯度洗脱,采用电喷雾离子源(ESI)在正离子多反应监测(MRM)模式下进行测定。万古霉素、去甲万古霉素在4～5 000μg/L范围内呈良好的线性关系,相关系数(r2)大于0.99。空白基质样品在15、60、150μg/kg加标水平的平均回收率均大于80%,相对标准偏差均小于5%。万古霉素、去甲万古霉素的方法检出限(LOD)分别为0.5、0.8μg/kg,定量下限(LOQ)分别为2.0、3.0μg/kg。该方法实用性强、准确性好、灵敏度高,适用于乳和乳制品中万古霉素、去甲万古霉素残留量的测定。     

丙烯腈单收液组成分析

采用HP-INNOWAX大孔径毛细管色谱柱对丙烯腈单收液进行分离,经气相色谱-质谱联用分析,对24种组分进行定性。用氢火焰离子化检测器检测,采用内标法对样品中的杂质进行了定量分析。相对标准偏差和相对误差均小于10%。     

Determination of Zy 17617B in plasma by solid-phase extraction and liquid chromatography with automated pre-column exchange.

An automated chromatographic system, combining solid-phase extraction and automated pre-column exchange, is described for the routine determination of Zy 17617B at the pmol/ml level in human plasma. The sample extraction and elution onto the analytical column were performed automatically and concomitantly using a conventional liquid chromatographic apparatus equipped with a Merck OSP-2 on-line sample preparator. Validation data demonstrate the reliability of the method.     

Design of a portable gas chromatography with a conducting polymer nanocomposite detector device and a method to analyze a gas mixture

A portable chromatography device and a method were developed to analyze a gas mixture. The device comprises a chromatographic column for separating components of a sample of the gas mixture. It has an air pump coupled to the inlet of a chromatographic column for pumping air and an injector coupled to the inlet of chromatographic column for feeding the sample using the air as a carrier gas. A detector is arranged downstream from and coupled to the outlet of the chromatographic column. The detector is a nanostructure semiconductive microfiber. The device further comprises an evaluation unit arranged and configured to evaluate each detected component to determine the concentration. The designed portable system was used for simultaneous detection of amines. The possibility of applying dispersive liquid–liquid microextraction for the determination of analytes in trace levels is demonstrated. The reproducibility of this method is acceptable, and good standard deviations were obtained. The relative standard deviation value is less than 6% for all analytes. Finally, the method was successfully applied to the extraction and determination of analytes in water samples.     

Établissement du profil chromatographique liquide non aqueux des métabolites phytochimiques apolaires des phytomédicaments

Chromatographic profiling of plant metabolites is therefore a good tool for quality control of such herbal medicinal products. Our objective was to propose a protocol for sample preparation and liquid chromatographic profiling of non-polar metabolites for quality assessment of African herbal medicinal products. The methodology is based on the chemometric assessment of liquid chromatographic profiles of non-polar metabolites issued from several batches of leaves of Combretum micranthum and Mitracarpus scaber. Metabolic profiling is carried out by non-aqueous liquid chromatography on porous carbon graphite, coupled with mass spectrometry, after extraction with dichloromethane and removal of chlorophyll. Our method using liquid chromatography, coupled to mass spectrometry can detect non-polar metabolites already identified in the two herbal drugs. Chemometric data analysis of chromatographic profiles using the PLS-discriminant analysis with or without orthogonal signal correction, allowed a distinction between the two herbal drugs.     

疏水型色谱饼对人血清蛋白质组学样品的快速分离与制备

建立了疏水型色谱饼(10 mm×20 mm i.d.)与反相色谱(RPLC)离线二维色谱快速分离制备人血清蛋白质组学样品,并用基体辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)进行检测的方法。以4种标准蛋白质的稀溶液为模型进行分离富集,得到细胞色素c(Cyt-c)与肌红蛋白(Myo)的检出限均为1 pmol/μL,溶菌酶(Lys)和胰岛素（Ins）的检出限为0.1 pmol/μL。将此方法用于人血清蛋白质组学样品的分离与制备,随着血清处理量的增大,质谱可检出的组分数目与信号强度均增加,当血清处理量达到1.0 mL时,可检出低丰度蛋白质或多肽285个(相对分子质量均在15000以下)。研究中将1 μg Cyt-c加入到0.5 mL血清中,用上述方法在分离富集低丰度Cyt-c上取得了很好的效果。结果表明,采用疏水型色谱饼与反相色谱联用技术不仅可对血清样品中低丰度蛋白质进行有效的分离和富集,而且一次样品的处理量大,可显著提高低丰度蛋白质的分析、检测水平。     

Comprehensive two-dimensional separations of complex mixtures using reversed-phase reversed-phase liquid chromatography

A comprehensive two-dimensional reversed-phase reversed-phase liquid chromatographic system for the separation of a complex mixture of oligostyrenes was developed using results from a previous theoretical assessment of the informational similarity, percent synentropy, orthogonality and peak capacity of hypothetically coupled systems. The degree of sample attribute order in the first separation dimension was also used in the development of the experimental two-dimensional system. A C18(methanol)/CCZ(acetonitrile) two-dimensional system was chosen for the comprehensive analysis of the oligostyrene mixtures because this system had the lowest solute crowding, highest orthogonality and was observed to have order with respect to a sample attribute in the first separation dimension. The separations achieved were in full agreement with the results from information theory and (a geometric approach to) factor analysis assessments. High sampling rates in the first liquid chromatographic dimension were shown to be impossible or inefficient when the peak capacity and separation time of the second dimension was high or when the aim of the exercise was to isolate individual sample constituents in high yield.     

5,5′-二硫硝基苯甲酸柱前衍生高效液相色谱法测定酶促反应液中的L-半胱氨酸

以5,5′-二硫硝基苯甲酸(DTNB)为柱前衍生试剂对酶促反应液进行衍生化,用C18色谱柱在室温下采用二元梯度洗脱,于330 nm波长下检测,同时以2-巯基乙醇和二硫苏糖醇(DTT)为对照,对L-半胱氨酸的分离峰进行确认,并对酶促反应液中的L-半胱氨酸进行分离测定。L-半胱氨酸浓度为5~950 μmol/L时,其浓度与峰面积呈显著的线性关系。高、中、低浓度水平的L-半胱氨酸加标回收率为99.7%~100.5%,相对标准偏差小于1.3%,检测限为0.8 μmol/L。方法简便、快速、可靠。用于样品分析,结果     

酚类环境雌激素的色谱分析方法

综述了近年来酚类环境雌激素的色谱分析研究进展,包括气相色谱和气质联用,高效液相色谱和各种检测器联用技术。比较了使用气相色谱和液相色谱两种方法的优缺点,并对环境雌激素样品预处理作了介绍。     

Determination of Plasma Pseudo-Ephedrine by Fluorescence Detection and High Performance Liquid Chromatography

Abstract

A sensitive and specific high-performance liquid chromatographic method has been developed for the determination of pseudoephedrine in plasma. The assay was based on the production of a highly fluorescent derivative of pseudoephedrine using 4-chloro-7-nitrobenzo-2, 1, 3-oxadiazole (NBD-Cl) as the derivatization agent. The fluorescent derivatives were separated using normal phase liquid chromatography after an automated, column-switching, sample clean-up procedure. Pseudoephedrine determination was accurate and precise at concentrations as low as 10 nanograms per milliliter of plasma. The chromatographic step separated derivatives of pseudoephedrine from those of norpseudoephedrine and several other amines. Measurement of pseudoephedrine concentrations in plasma following a single 120 milligram oral dose is illustrated.     

Determination of Ro 14-1761, a new third-generation cephalosporin, in the plasma and milk of cattle by column switching high-performance liquid chromatography

A sensitive and specific high-performance liquid chromatographic procedure was developed for the determination of the third-generation cephalosporin Ro 14-1761 in cow plasma and milk. The molecular structure of the new antimicrobial was very close to that of ceftriaxone, but the high-performance liquid chromatographic methods available for the latter could not be used as Ro 14-1761 adsorbed and/or degraded during the chromatographic process. Furthermore, the high-performance liquid chromatographic technique derived for ceftriaxone was not sensitive enough for our purposes. In the new assay, the plasma (milk) protein was precipitated with acetonitrile after dilution of the sample with water. For low concentrations (less than or equal to 10 micrograms/ml), the supernatant obtained after centrifugation was concentrated by extracting acetonitrile with methylene chloride. Quantification was performed by column switching high-performance liquid chromatography with UV detection (274 nm) using ion-pair reversed-phase chromatography. Ethylenediaminotetraacetic sodium salt had to be added to the mobile phase (1.2 mM) to prevent adsorption and/or degradation of the cephalosporin on the analytical column. The selectivity of the chromatographic separation was enhanced by heating the column to ca. 50 degrees C. The drug recovery was better than 85%. The limit for quantitative determination in both milk and plasma was 0.1 microgram of Ro 14-1761 per millilitre with an accuracy of 1% (coefficient of variation 10%). The overall accuracy and precision were 1-10% in the 0.1-100 micrograms/ml concentration range.