辉光放电质谱仪期间核查控制图在实验室质量控制中的应用

仪器设备的期间核查是实验室管理及实验室认证认可的一项基本要求,辉光放电质谱仪主要应用于高纯金属材料的分析,标样研制较为困难,使用高纯标准物质进行质量控制及期间核查的方法难以实现。对用液氮低温冷却离子源型的辉光放电质谱仪,使用纯钽片在进行日常仪器调试信号时得到的钨元素含量数据,用于绘制平均值-极差控制图作为实验室质量控制及期间核查的判定依据,以此评价仪器日常工作的性能状态,以保证检测结果的正确性和可靠性。     

液相色谱-质谱联用接口技术的研制及性能表征

自制了一套液相色谱-质谱联用接口,接口包含大气压接口、离子源及连接高效液相色谱进样器和质谱采集软件的电子通讯接口。成功地将赛默飞世尔高效液相色谱戴安U3000与团队自主研制的APITOFMS10000相连。实验结果表明,自行搭建的液质联用仪有很好的稳定性(RSD=5.6%),线性相关系数(r2)为0.995 8,线性范围为2~2 000 pg,定量下限为2 pg,检出限为0.5 pg。可明显检出吡罗昔康、茶碱和泼尼松3种标准药品。实验数据表明自行研发的液相色谱-质谱联用接口满足应用要求,搭建的液相色谱-质谱联用仪在生物化学、医药分析、食品安全、环境检测等领域具有应用潜力。     

高效液相色谱-质谱联用技术的应用进展

高效液相色谱-质谱联用技术具有高分离能力、高灵敏度、应用范围广和极强的专属性等特点。对高效液相色谱-质谱联用技术在药物分析、食品分析和环境分析等领域的应用,特别是在中草药成分分析、中药指纹图谱研究、药物代谢研究、体内药代动力学研究、西药及中成药成分分析、药物筛选研究等方面的应用进行了综述。     

理化实验室仪器设备的期间核查方法——以气相色谱仪的核查为实例

CNAS-CL01《检测和校准实验室能力认可准则》[1]及《实验室资质认定评审准则》[2]中要求实验室进行测量设备的期间核查。所谓"仪器设备期间核查"就是在两次正规的检定/校准间隔的期间,进行仪器的核查。其意义在于检查测量仪器的校准状态在校准有效期内是否得到保持,增加保持设备校准状态的可信度,防止使用不符合技术规范要求的仪器设备。通过期间核查及时发现出现的量值失准及缩短失准后的追溯时间,当核查发现不允许的偏     

HPLC-MS测定大鼠血浆中单硝酸异山梨酯

建立了高效液相色谱-质谱法测定血浆中单硝酸异山梨酯浓度的方法.以茶碱为内标,样品在碱性条件下,用乙酸乙酯提取,高效液相色谱-质谱(MSD)检测.线性范围为0.034 64~103.0 mg/L,回收率为93.1%~112.0%,相对标准偏差小于6%.该法处理血浆简单,检测结果准确度高,专一性强,适用于药代动力学和生物利用度研究.     

《液相色谱质谱联用技术在食品和药品分析中的应用》

随着现代仪器分析的发展,液相色谱质谱联用技术(LC/MS)日趋成熟,并在科研与生产中发挥了重要作用。该书由三部分组成:第一部分基础理论,介绍了液相色谱和质谱的工作原理、仪器结构及工作条件、LC/MS接口、质谱信息解析;     

环境监测常用测量仪器期间核查方法及实例

<正>期间核查是指为保持测量仪器校准/检定状态的可信度,而对仪器示值(或其修正因子或修正值)在规定时间间隔内是否保持其在规定最大允许误差或扩展不确定度或准确度等级内的核查。其目的就是在一个检定/校准周期内,防止使用不符合技术规范要求的仪器设备[1]。期间核查是实验室确保检测结果的行之有效的内部质量控制活动。环境监测中所用测量仪器种类多、数量大,部分测量仪器使用频率高、使用环境条件恶劣,测量仪器性能直接影响测     

气相色谱-质谱法测定大鼠血浆中尼古丁及其药物代谢动力学研究

采用气相色谱-质谱法测定大鼠血浆中的尼古丁。血浆样品采用蛋白沉淀法净化,采用DB-Wax毛细管色谱柱分离,质谱中选择电子轰击离子源和选择离子监测模式,以茴香脑为内标进行定量。并采用PKSlover 2.0软件计算药代动力学参数。尼古丁的线性范围为0.10~2.0mg·L-1,检出限为4.59μg·L-1。对空白样品进行加标回收试验,回收率在85.0%~90.1%之间,相对标准偏差(n=6)小于3.0%。应用此方法考察了灌胃给药的大鼠血浆样品中尼古丁代谢动力学特点,主要动力学参数AUC0-t,AUC0-∞,Tmax和ρmax分别为8.570mg·L-1·h-1,10.49mg·L-1·h-1,1.0h,998.9μg·L-1,结果呈现药物代谢动力学过程。     

高效液相色谱串联质谱法测定酸铜电镀液中硫代丙烷磺酸钠

基于高效液相色谱串联质谱建立了酸铜电镀液中硫代丙烷磺酸钠光亮剂的定性定量分析方法。以聚二硫二丙烷磺酸钠（SPS）和3-巯基-1-丙烷磺酸钠（MPS）为标准样品，以配置喷射流电喷雾离子源三重四级杆的高效液相色谱质谱联用仪为测试仪器，采用C18反相色谱柱，乙酸铵水溶液-乙腈为流动相。采用硫酸水溶液配制不同浓度梯度的SPS和MPS混合标准溶液，以标准样品的母离子和子离子作为定性定量离子，分别建立SPS和MPS的标准工作曲线，两者的质量浓度在0.05～2 mg/L范围内，标准工作曲线的线性相关系数均大于0.999 9，样品的加标回收率为96.8%～106.7%，测定结果的相对标准偏差小于2.0%(n=6)，聚二硫二丙烷磺酸钠和3-巯基-1-丙烷磺酸钠的检出限分别为0.003 0、0.003 6 mg/L，定量限分别为0.010 0、0.012 0 mg/L。该方法可应用于电镀工厂对电镀液中微量硫代丙烷磺酸钠光亮剂的检测分析。     

《液相色谱质谱联用技术在食品和药品分析中的应用》

随着现代仪器分析的发展,液相色谱质谱联用技术(LC/MS)日趋成熟,并在科研与生产中发挥了重要作用。该书由三部分组成:第一部分基础理论,介绍了液相色谱和质谱的工作原理、仪器结构及工作条件、LC/MS接口、质谱信息解析;第二部分食品功能成分分析,介绍了LC/MS方法分析食品中的蛋     

Implementation of DART and DESI ionization on a fieldable mass spectrometer

A recently developed prototype mobile laboratory mass spectrometer, incorporating an atmospheric pressure ionization (API) interface, is described. This system takes advantage of the small size, lower voltage requirements, and tandem MS abilities of the cylindrical ion trap mass analyzer. The prototype API MS uses small, low-power pumps to fit into a 0.1-m(3) self-contained package weighing <45 kg. This instrument has been adapted to allow rapid interfacing to electrospray ionization, desorption electrospray ionization, and direct analysis in real-time sources. Initial data indicate that these techniques provide rapid detection and identification of compounds for quality control, homeland security, and forensic applications. In addition, this instrument is self-contained and compact, making it ideally extensible to mobile laboratory and field analyses. Initial MS and MS/MS data for analyses of drugs, food, and explosives are presented herein.     

Electron ionization in LC-MS: recent developments and applications of the direct-EI LC-MS interface

The purpose of this article is to underline the possibility of efficiently using electron ionization (EI) in liquid chromatography (LC) and mass spectrometry (MS). From a historical perspective, EI accompanied the first attempts in LC-MS but, owing to several technical shortcomings, it was soon outshined by soft, atmospheric pressure ionization (API) techniques. Nowadays, two modern approaches, supersonic molecular beam LC-MS and direct-EI LC-MS, offer a valid alterative to API, and preserve the advantages of EI also in LC-MS applications. These advantages can be summarized in three crucial aspects: automated library identification; identification of unknown compounds, owing to EI extensive fragment information; inertness to coeluted matrix interferences owing to very unlikely ion–ion and ion–molecule interactions in the EI gas-phase environment. The direct-EI LC-MS interface is a simple and efficient solution able to produce high-quality, interpretable EI spectra from a wide range of low molecular weight molecules of different polarity. Because of the low operative flow rates, this interface relies on a nano-LC technology that helps in reducing the impact of the mobile phase on the gas-phase environment of EI. This review provides an extensive discussion on the role of EI in LC-MS interfacing, and presents in detail several performance aspects of the direct-EI LC-MS interface, especially in terms of response, mass-spectral quality, and matrix effects. In addition, several key applications are also reported.     

A compact liquid chromatography-mass spectrometry instrument for the quantitation of immunosuppressants

Liquid chromatography tandem mass spectrometry (LC-MS/MS) plays an important role in clinical diagnostics. Although LC-MS/MS is superior in terms of accurately quantifying molecules in complex matrices, instrument footprint, operation and maintenance complexity also hinder its expansion as the analytical technique of choice. In this study, a compact LC-MS instrument was developed, in which an assembled liquid chromatograph was coupled with a miniature ion trap mass spectrometer. The overall instrument has a footprint of 69 cm × 31 cm × 31 cm, and it requires no gas supply as well as minimum maintenance. Furthermore, the use of LC-MS is in accord with conventional clinical diagnostic protocols, and the choice of ion trap offers tandem MS performance. The results showed that the use of LC could improve both mixture analysis capability and detection sensitivity of the miniature mass spectrometer. After optimization, feasibility of this instrument in clinical practice was demonstrated by the quantitation of four widely used immunosuppressants in blood samples. Relatively good linearities were obtained, which spanned the reference ranges of effective therapeutic concentrations of each immunosuppressant. Intra-day and inter-day accuracy and precision of analytical method were also assessed. This work showed that a compact LC-MS instrument could be used in clinical diagnosis, either to replace conventional lab-scale instruments or to be used in POCT applications.     

Solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry for determination of trace rosiglitazone in urine

This project evaluated solid-phase extraction (SPE) combined with liquid chromatography-tandem mass spectrometry (LC-MS/MS) to determine the trace amount of rosiglitazone in human urine. The analytical performance of four modes of LC-MS and tandem MS operation (atmospheric pressure chemical ionization (APCI), electrospray ionization (ESI), positive and negative ionization) was compared for two mass spectrometers, a triple-quadrupole and a quadrupole ion trap instrument. Rosiglitazone was extracted from urine using a SPE cartridge of 50mg C8 sorbent and acetonitrile used as the eluting solvent. Samples were then separated on a RP18 column interfaced with a tandem mass spectrometer. The recovery of rosiglitazone was greater than 91.2%. The urine assay combining SPE and LC-APCI-MS/MS of triple-quadrupole was proved a very selective and sensitive method for determination of trace rosiglitazone. The assay was linear over a wide range, with a lower limit of quantification of 0.1 ng/mL using 1 mL of urine. The intra- and inter-day precisions were <9.8% and <7.9%, respectively, and the accuracies were in the range 91.0-103.6%. The rosiglitazone concentration profile in human urine was also determined. The results of this study reveal the adequacy of SPE-LC-APCI-MS/MS method for analyzing rosiglitazone from diabetic patients' urines. The concentrations of rosiglitazone were detected to range from 760 to 164 pg/mL.     

液相色谱-串联质谱法测定水产品中麻醉剂MS-222残留

建立了液相色谱-串联质谱法测定水产品中麻醉剂3-氨基苯甲酸乙酯甲基磺酸盐(MS-222)残留量的方法。提取液为50%的甲醇及乙酸-乙酸钠缓冲溶液,提取液经C18固相萃取柱净化处理后用液相色谱-串联质谱仪进行测定,外标法定量。流动相为0.5%的甲酸溶液和乙腈(V:V=60:40),流速为0.2 mL/min。该方法的线性范围为0.001～1.0 mg/L,相关系数大于0.999,检出限为1μg/kg,定量限为2μg/kg。加标回收率可以达到80%～110%。     

Near infrared and Raman spectroscopy as Process Analytical Technology tools for the manufacturing of silicone-based drug reservoirs

Using near infrared (NIR) and Raman spectroscopy as PAT tools, 3 critical quality attributes of a silicone-based drug reservoir were studied. First, the Active Pharmaceutical Ingredient (API) homogeneity in the reservoir was evaluated using Raman spectroscopy (mapping): the API distribution within the industrial drug reservoirs was found to be homogeneous while API aggregates were detected in laboratory scale samples manufactured with a non optimal mixing process. Second, the crosslinking process of the reservoirs was monitored at different temperatures with NIR spectroscopy. Conformity tests and Principal Component Analysis (PCA) were performed on the collected data to find out the relation between the temperature and the time necessary to reach the crosslinking endpoints. An agreement was found between the conformity test results and the PCA results. Compared to the conformity test method, PCA had the advantage to discriminate the heating effect from the crosslinking effect occurring together during the monitored process. Therefore the 2 approaches were found to be complementary. Third, based on the HPLC reference method, a NIR model able to quantify the API in the drug reservoir was developed and thoroughly validated. Partial Least Squares (PLS) regression on the calibration set was performed to build prediction models of which the ability to quantify accurately was tested with the external validation set. The 1.2% Root Mean Squared Error of Prediction (RMSEP) of the NIR model indicated the global accuracy of the model. The accuracy profile based on tolerance intervals was used to generate a complete validation report. The 95% tolerance interval calculated on the validation results indicated that each future result will have a relative error below ±5% with a probability of at least 95%. In conclusion, 3 critical quality attributes of silicone-based drug reservoirs were quickly and efficiently evaluated by NIR and Raman spectroscopy.     

高效液相色谱-三重四级杆质谱快速筛查及定量检测改善睡眠类保健品和中成药中的22个精神类化合物

液相色谱串联三重四极杆质谱（liquid chromatography tandem triple quadrupole mass spectrometry, LC-MS/MS）广泛应用于环境分析、食品安全、药物代谢研究、生物医学等领域,主要用于复杂样品基质中痕量目标物检测,既适用于小分子有机化合物定性,又可用于痕量化合物定量. 其主要检测模式是多反应监测模式（multiple reaction monitoring, MRM）,以定性离子对的丰度比来进行定性,以定量离子对的峰响应进行定量,在MRM检测模式下具有出色的检测灵敏度和定量功能. LC-MS/MS的合理规范使用与维护保养,是保证检测数据准确有效、仪器可持续正常运行的基本要求,也是降低仪器维修成本的重要举措. 阐述了安捷伦LC-MS/MS的工作原理、开机与关机、调谐,探讨了常见的故障及应对措施、日常维护保养的内容,旨在为合理规范使用仪器提供参考.

     

Comparison of sub-2-microm particle columns for fast metabolite ID

The use of sub-2-microm particle columns for fast high throughput metabolite ID applications was investigated. Three LC-MS methods based on different sub-2-microm particle size columns using the same analytical 3 min gradient were developed (Methods A, B, and C). Method A was comprised of a 1.8 microm particle column coupled to an MS, methods B and C utilized a 1.7 microm particle column (BEH 50 x 2.1 mm2 id) and 1.8 microm particle column coupled to a Q-TOF MS. The precision and the separation efficiency of the methods was compared with repeated standard injections (N=10) of reference compounds verapamil (VP), propranolol, and fluoxetine. Separation efficiency and MS/MS spectral quality were also evaluated for separation and detection of VP and its two major metabolites norverapamil (NVP) and O-demethylverapamil (ODMVP) in human-liver microsomal incubates. Results show that 1.8 microm particle columns show similar performance for separation of VP and its major metabolites and comparable spectral quality in MS(E) mode of the Q-TOF instrument compared to 1.7 microm particle columns. Additionally, the study also confirmed that sub-2-microm particle size columns can be operated with standard analytical HPLC but that performance is maximized by integrating column in UPLC method with reduced void volumes. All the methods are suitable for the determination of major metabolites for compounds with high metabolic turnover. The high throughput metabolite profile analysis using 384-well plate format of up to 48 compounds in incubates of human-liver microsomes was discussed.     

Development and application of a quantitative lateral flow immunoassay for fumonisins in maize

A quantitative lateral flow immunoassay for measuring fumonisins in maize was developed. Strip preparation and assay parameters were optimized to obtain a dipstick usable outside the laboratory with different samples, and which shows performance comparable with that of other screening methods, as confirmed by the intra- and the inter-day precision of data (RSD 5-16%). Quantification was obtained by an external calibration curve, which can be stored and used for measurements made with strips of the same batch in different days and at varying temperatures (22-37°C). Limit of detection (120 μgL(-1)) and dynamic range (200-5000 μgL(-1)) allow the direct assessment of fumonisin contamination at all levels of regulatory relevance. Twenty-seven maize samples were analyzed after a simple sample preparation which avoids the use of organic solvent. Linear correlation was observed (y=1.071x-0.2, r(2)=0.990) when data was compared with that obtained through a reference LC-MS/MS method, across a wide range of fumonisin contamination.     

Comparison of liquid chromatography/mass spectrometry, ELISA, and phosphatase assay for the determination of microcystins in blue-green algae products

More than 100 samples of blue-green algae products (consisting of Aphanizomenon, Spirulina, and unidentified blue-green algae) in the form of pills, capsules, and powders were collected from retail outlets from across Canada. The samples were extracted with 75% methanol in water and centrifuged to remove solids. Aliquots of the extracts along with spiked blank sample extracts were sent to each participating laboratory and independently analyzed for microcystins by enzyme-linked immunosorbent assay (ELISA), protein phosphatase inhibition assay, and by liquid chromatography-tandem mass spectrometry (LC-MS/MS) after sample cleanup using C18 solid-phase extraction. The results obtained by ELISA and LC-MS/MS agreed very well over a concentration range of about 0.5-35 microg/g. The colorimetric phosphatase results generally agreed with the other 2 methods. While the 2 biochemical assays measured total microcystin content compared with a standard of microcystin LR, the LC-MS/MS method measured specific microcystins (LA, LR, RR, YR) using external standards of these for identification and quantitation. Microcystin LR was found in all positive samples by LC-MS/MS. Microcystin LA was the only other microcystin found in the samples analyzed. These 2 microcystins represent essentially all the microcystins that were present in the extracts. Otherwise, the LC-MS/MS results would have been significantly lower than the results of the biochemical assays had other unknown microcystins been present.