液相色谱串联质谱法测定血清维生素A、E含量

目的 建立液相色谱串联质谱法(LC-MS/MS法)测定血清维生素A和维生素E含量的方法.方法 采用硫酸锌沉淀蛋白,96孔蛋白沉淀板过滤.采用LCMS/MS[正离子电喷雾离子化(ESI+)的多反应监测模式(MRM)]氘代同位素内标法检测血清维生素A、E含量并进行相关方法学验证.结果 LC-MS/MS检测血清维生素A的批内精密度变异系数为3.2％(2.4％～3.9％),批间变异为5.5％(5.O％～6.0％);维生素E的批内精密度变异系数为4.1％(3.0％～5.1％),批间变异为8.0％(7.6％～8.3％).维生素A在0.06 ～2 μg/mL、维生素E在1.2 ～ 40μg/mL范围内线性良好,线性相关系数分别为0.9987、0.9909.维生素A、维生素E的定量限分别为0.03μg/mL、0.8μg/mL;检测限分别为0.02μg/mL and 0.01 μg/mL.维生素A低浓度回收率为107.5％,高浓度为106.9％;维生素E的低浓度回收率为91.9％,高浓度为88.4％.与液相色谱方法进行比对,两种方法的结果差异无统计学意义(P值均大于0.30)说明两种方法具有一致性.结论 LC-MS/MS检测血清维生素A及维生素E的灵敏度高,结果准确、稳定,可应用于临床分析.     

高效液相色谱-串联质谱法定量测定大鼠血浆中LMV-12(HE003)及其代谢产物M4

目的 建立一种高效液相色谱-串联质谱法(HPLC-MS/MS)同时测定SD大鼠血浆中LMV-12(HE003)(以下简称LMV-12)及其活性代谢产物M4的方法,并开展完整的生物分析方法学验证.方法 采用蛋白沉淀提取血浆中LMV-12及M4,用HPLC-MS/MS方法进行定量分析.采用ACQUITY HPLC?CSH ...     

液相色谱串联质谱法检测微量血维生素D含量

目的建立液相色谱串联质谱法(LC- MS/MS法)测定微量血维生素D含量的方法。方法采用非衍生处理方法,利用正离子电喷雾离子化(ESI+)、多反应监测模式(MRM)、同位素内标法检测微量血维生素D含量并进行相关方法学验证。结果 vitD2在5~100 ng/mL、vitD3在5~150 ng/mL范围内线性良好,线性相关系数分别为0.9988、0.9984。vitD2和vitD3的批内精密度和批间精密度变异系数均小于10%。vitD2低浓度回收率为87.58%,高浓度为94.68%;vitD3的低浓度回收率为92.62%,高浓度为87.65%。vitD2、vitD3的LOD分别为0.36 ng/mL和1.33 ng/mL,LOQ分别为2.5 ng/mL和2.5 ng/mL。患者样本在4℃的稳定性较好,可至少保存7d。vitD2和vitD3的携带污染分别为0.06%和 0.07%,满足要求。结论此LC- MS/MS检测法不仅样本用量少,而且操作简单,无污染,更适合临床检测分析。     

原子吸收法测定大米粉中镉的不确定度评定

目的 采用无火焰原子吸收法对大米粉中的镉进行测定。方法 分析测量不确定的主要来源,在整个分析测定过程:称量、容量器具的体积、标准物质、直线回归方程、重复性测定和仪器示值误差等是不确定度的主要来源。结果 按照JJF 1059.1-2012《测量不确定度评定与表示》的规定进行评定,舍弃贡献小,可以忽略不计的不确定度分量,最终计算给出扩展不确定度为: K=2,U=48 μg/kg,CCd=（300.01±48.00）μg/kg。结论 该结果更加客观和接近真值,降低了检测机构的检测风险。     

医用激光可达发射极限的测量及其不确定度评定

目的本文旨在测量表观光源、连续发射的医用激光的可达发射极限,并评定其不确定度。方法根据GB7247．1—2001《激光产品的安全第一部分：设备分类、要求和用户指南》的要求,测量光路由两个圆孔光栅、毫瓦（瓦）级激光功率计和激光输出终端锁定装置组成,激光输出终端锁定装置用于固定激光终端和探测器的相对位置,并对测量结果进行不确定度评定。结果实现了可达发射极限的测量,同时对不确定度评定的结果进行了分析,对降低医用激光测量不确定度给出了建议。结论本文所述方法对其他类型激光有参考价值,并对GB7247．1—2001的再修订给出了建议。     

血清淀粉酶分析中不确定度评定方法的比较与选择

目的 比较血清淀粉酶(AMY)分析中不确定度的评定方法,根据现有数据来源和实际需求选择合适的评定方法。方法 参考CNAS-GL037文件中的方法测量2个浓度水平冰冻人血清AMY国家标准物质各5批、每批3次;采用JCTLM参考方法和常规方法同时测量40份浓度为(41.2～1 237.0)U/L单人份血清标本各2次;收集2015至2020年我院卫健委正确度验证计划数据;测量2个浓度水平人血清标本各5批、每批5次;收集我院半年内同一批号2个浓度水平室内质控在控数据。参考CNAS-TRL-001:2012文件中的方法,采用以上来源的数据分别计算由测量偏倚引入的不确定度分量[u_crel(bias)]和由实验室内测量复现性引入的不确定度分量[u_rel(R_w)]。分别将不同来源数据计算的u_crel(bias)和u_rel(R_w)两两组合计算相对合成标准不确定(u_crel)。比较结果差异,分析实验室如何选择合适的评定方法。结果 采用测量标准物质的数据、...     

“自上而下”法评定检验项目的测量不确定度

目的 对本核医学实验室电化学发光检验项目的测量不确定度进行评价.方法 依据CNAS技术报告“医学实验室一测量不确定度的评定与表达”,采用“自上而下”的方法,评定偏移和实验室内测量复现性两部分分量引入的不确定度并合成,计算相对扩展不确定度.结果 本核医学实验室电化学发光检验项目的相对扩展不确定度分别是AFP,8.56％;CEA,12.01％;t-PSA,11.87％;f-PSA,12.14％;FER,16.32％;CA125,8.53％;CA15-3,11.89％;CA19-9,9.40％(k=2).结论 核医学实验室对定量项目的测量不确定度进行评定很有必要.     

蒸馏酒中甲醇测量结果不确定度分析

目的 蒸馏酒中的甲醇含量测量是衡量白酒质量安全的重要卫生指标之一,本文研究用气相色谱法检测蒸馏酒中甲醇含量测量结果的不确定度.方法 以蒸馏酒及配制酒卫生标准的分析方法测酒中甲醇含量的方法,根据数学模型从标准溶液浓度、注射器体积、酒精度测量、稀释系数几个不确定分量进行了计算.结果 气相色谱法检测蒸馏酒中甲醇含量测量结果不确定度为0.0004g/100mL.结论 在检测研究中进行不确定度分析,可了解被测值波动的置信区间范围,反应测量结果的质量水平.     

Sequence-Level and Dual-Phase Identification of Salmonella Flagellum Antigens by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Forty-three reference strains involving the 24 most common serovars of Salmonella enterica were examined by using a mass spectrometry-based H antigen typing platform (MS-H). The results indicate that MS-H can be used as a sensitive, rapid, and straightforward approach for the typing of Salmonella flagella at the molecular level without antiserum and phase inversion.     

Determination of Volatile Aroma Compounds of Ganoderma Lucidum by Gas Chromatography Mass Spectrometry (HS-GC/MS)

This study was conducted at Horticulture Department of Cukurova University, Adana, Turkey during 2010–2011. Fresh sample of Ganoderma lucidum collected from Mersin province of Turkey was used as material. Volatile aroma compounds were performed by Headspace Gas Chromatography (HS-GC/MS). Alcohols, aldehydes, acids, phenol, L-Alanine, d-Alanine, 3Methyl, 2-Butanamine, 2-Propanamine were determined. 1-Octen-3-ol (Alcohol) and 3-methyl butanal (Aldehyde) were identified as major aroma compounds.     

高效液相色谱-串联质谱法测定人血浆盐酸伪麻黄碱浓度

目的 建立一种高效液相色谱-质谱联用技术（LC-MS/MS）测定人血浆盐酸伪麻黄碱浓度的方法。方法 血浆样品经液液萃取后,以甲醇∶水∶甲酸（60∶40∶1,V/V/V）为流动相,流速0.35 ml/min,采用Cap cell pack C18色谱柱分离,150 mm×2.1 mm, 5 μm（USA）;柱温20℃,选择离子喷雾离子化源串联质谱,通过正离子方式检测;选择反应监测（MRM）方式转化m/z=166.3/148.2（盐酸伪麻黄碱）和m/z= 152.2/134.15（内标苯丙醇胺）进行定量分析,用内标法测定含量。结果 伪麻黄碱浓度分别在5.0~400.0 ng/ml的范围内线性良好,R=0.9962,最低检测限为1.0 g/ml。结论 本方法操作简便、快速,结果准确,可用于该药物的含量测定,同时也可为临床药动学研究提供一定的参考。     

LC-MS/MS测定大鼠血浆中黄藤素含量及其药代动力学研究

目的建立大鼠血浆中黄藤素的LC-MS/MS定量方法,并利用此方法考察黄藤素在大鼠体内的药物动力学。方法色谱柱为ZorbaxEclipseXDB-C1(82.1mm×50mm,1.8μm),流动相为0.1%甲酸溶液-乙腈(70:30),采用多级反应模式(MRM)检测;通过大鼠眼底静脉取血,血浆经乙腈沉淀蛋白,取上清液进行LC-MS/MS分析,测定黄藤素血药浓度,通过DAS2.0计算其药动学参数。结果血浆中黄藤素在0.442~44.2ng/ml范围内呈现良好的线性关系,方法学精密度、回收率、稳定性等均符合要求;大鼠体内黄藤素药动学符合二室模型特征,灌胃给予40mg/kg黄藤素后,大鼠血浆中的黄藤素浓度在2.8h达峰值,t1/2为6h,最大血药浓度为19.8ng/ml。结论本研究建立的大鼠体内黄藤素测定方法灵敏度高、专一性好,可用于黄藤素的体内药物动力学研究,为黄藤素应用研究提供了有力支持。     

LC-MS/MS法测定家兔血浆中奥昔布宁浓度及其在生物等效性评价中的应用

目的建立家兔血浆中奥昔布宁的液相色谱-串联质谱联用(HPLC-MS/MS)定量方法,用于评价自制盐酸奥昔布宁凝胶和国外上市品Gelnique的生物等效性。方法以盐酸苯海拉明为内标,血浆样品经0.5 mol/L NaOH碱化后采用叔丁基甲醚液-液萃取。用Kinetex C₁₈色谱柱分离,流动相采用水相(1‰甲酸-10 mmol/L乙酸铵缓冲液)-乙腈(50∶50,v/v)进行洗脱;电喷雾离子源正离子检测,离子对为m/z 358→142(奥昔布宁),m/z 256→167(苯海拉明)。用以上方法测定家兔单次经皮给予自制盐酸奥昔布宁凝胶和Gelnique后血浆中奥昔布宁的浓度,评价两者的生物等效性。结果奥昔布宁在1~200μg/L范围内线性关系良好,低中高质控浓度的批间和批内精密度(RSD)介于1.67%~9.79%,准确度在92.9%~103%。自制盐酸奥昔布宁凝胶和Gelnique经评价生物等效。结论本方法简便,专属性强,灵敏度好且准确性高,适用于透皮制剂在家兔体内的药动学研究和生物等效性评价。     

Direct detection of extended-spectrum beta-lactamases (CTX-M) from blood cultures by LC-MS/MS bottom-up proteomics

Rapid bacterial species identification and antibiotic susceptibility testing in positive blood cultures have an important impact on the antibiotic treatment for patients. To identify extended-spectrum beta-lactamases (ESBL) directly in positive blood culture bottles, we developed a workflow of saponin extraction followed by a bottom-up proteomics approach using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The workflow was applied to positive blood cultures with Escherichia coli and Klebsiella pneumoniae collected prospectively in two academic hospitals over a 4-month period. Of 170 positive blood cultures, 22 (12.9%) contained ESBL-positive isolates based on standard susceptibility testing. Proteomic analysis identified CTX-M ESBLs in 95% of these isolates directly in positive blood cultures, whereas no false positives were found in the non-ESBL producing positive blood cultures. The results were confirmed by molecular characterisation of beta-lactamase genes. Based on this proof-of-concept study, we conclude that LC-MS/MS-based protein analysis can directly identify extended-spectrum beta lactamases in E. coli and K. pneumoniae positive blood cultures, and could be further developed for application in routine diagnostics.     

Identification of proteins from formalin-fixed paraffin-embedded cells by LC-MS/MS

There exists a need for robust approaches for tandem mass spectrometry (MS/MS)-based identification of proteins in formalin-fixed paraffin-embedded (FFPE) material. We demonstrate herein the identification of proteins in FFPE material using enzymatic cleavage for extraction of peptides from the FFPE specimen and liquid chromatography (LC) followed by MS/MS. We identified 324 proteins from a 3-year-old FFPE cell-block of a human lymphoma cell line. The identified proteins were assigned to the membrane, cytosol and nucleus, with diverse cellular functions. The results were comparable to those obtained with lysates from a fresh specimen of the lymphoma cell line. Western blotting analysis and immunofluorescence microscopy confirmed the expression of selected proteins. The functional significance of one protein (PKC eta) was validated using a PKC inhibitory peptide which resulted in lymphoma cell death in vitro. The ability to identify proteins from FFPE specimens has significant implications for MS/MS-based proteomics of vast repositories of archival primary tissue samples for disease-related discovery research.     

Comprehensive identification of proteins in Hodgkin lymphoma-derived Reed-Sternberg cells by LC-MS/MS

Mass spectrometry-based proteomics in conjunction with liquid chromatography and bioinformatics analysis provides a highly sensitive and high-throughput approach for the identification of proteins. Hodgkin lymphoma is a form of malignant lymphoma characterized by the proliferation of Reed-Sternberg cells and background reactive lymphocytes. Comprehensive analysis of proteins expressed and released by Reed-Sternberg cells would assist in the discovery of potential biomarkers and improve our understanding of its pathogenesis. The subcellular proteome of the three cellular compartments from L428 and KMH2 Hodgkin lymphoma-derived cell lines were fractionated, and analyzed by reverse-phase liquid chromatography coupled with electrospray ionization tandem mass spectrometry. Additionally, proteins released by Hodgkin lymphoma-derived L428 cells were extracted from serum-free culture media and analyzed. Peptide spectra were analyzed using TurboSEQUEST against the UniProt protein database (5.26.05; 188 712 entries). A subset of the identified proteins was validated by Western blot analysis, immunofluorescence microscopy and immunohistochemistry. A total of 1945 proteins were identified with 785 from the cytosolic fraction, 305 from the membrane fraction, 441 from the nuclear fraction and 414 released proteins using a minimum of two peptide identifications per protein and an error rate of <5.0%. Identification of proteins from diverse functional groups reflected the functional complexity of the Reed-Sternberg proteome. Proteins with previously reported oncogenic function in other cancers and from signaling pathways implicated in Hodgkin lymphoma were identified. Selected proteins without previously demonstrated expression in Hodgkin lymphoma were validated by Western blot analysis (B-RAF, Erb-B3), immunofluorescence microscopy (Axin1, Tenascin-X, Mucin-2) and immunohistochemistry using a tissue microarray (BRAF, PIM1). This study represents the first comprehensive inventory of proteins expressed by Reed-Sternberg cells of Hodgkin lymphoma and demonstrates the utility of combining cellular subfractionation, protein precipitation, tandem mass spectrometry and bioinformatics analysis for comprehensive identification of proteins that may represent potential biomarkers of the disease.     

Comparitive Study on Volatile Aroma Compounds of Two Different Garlic Types (Kastamonu and Chinese) Using Gas Chromatography Mass Spectrometry (HS-GC/MS) Technique

Backround

The medicinal use of garlic is much older than its usage as a food. The medical importance of garlic comes forward for its sulfur-containing components. In this study, it was aimed to compare Kastamonu garlic type with Chinese garlic type based on their aroma profiles.

Materials and Methods

Fresh Kastamonu garlic samples harvested from Kastamonu region of Turkey and Chinese garlic samples obtained from Turkish market were used as plant material. Volatile aroma compounds were determined using Headspace Gas Chromatography Mass Spectrometry (HS-GC/MS).

Results

Sixteen and twenty aroma components were identified in Kastamonu and Chinese garlic types, respectively. Kastamonu garlic type was found to be richer than Chinese garlic types in terms of sulfur-containing compounds. Diallyl disulphide, which is one of these components, was detected at level of 41.87% and 34.95% in the Kastamonu and Chinese garlic types, respectively. Also di-2-propenyl trisulfide was found only in Kastamonu garlic types. Disulfide, methyl 2-propenyl was determined at similar levels in both garlic types. Conclusion: The majority of garlic grown in Kastamonu region of Turkey is assessed by medical companies.

Conclusion

The results of the current study showed that Kastamonu garlic type has important medical properties. Therefore, this garlic can also be used in the medical field, as well as the consumption as food.     

电感耦合等离子体质谱法检测尿液中镍、铬含量

本文就使用电感耦合等离子体质谱仪同时测定尿液中镍、铬元素含量的方法进行了研究。样品经简单稀释后直接进样,采用动态反应池技术消除离子干扰,并使用内标进行校正。尿液中镍、铬元素的检出限分别为0.06μg/L和0.001μg/L,检测相对标准偏差在1.4%~4.7%间,加标回收率为99.1%~102.4%,同时质控样品值也落入可信参考范围。本方法样品处理简单,测量快速、灵敏、准确,值得临床推广应用。