liquid chromatography‐mass spectrometry

  • 文章类型: Journal Article
    背景:马尾藻(MTC),一种流行的中药,已广泛应用于肿瘤疾病的治疗。仙女草(PSC),这在外观上与MTC相似,是一种常见的假冒产品。传统方法难以有效区分MTC和PSC。因此,迫切需要一种快速准确的方法来识别MTC和PSC。
    目的:目的是通过分析非挥发性有机化合物(NVOC)的差异来区分MTC和PSC,味道,气味,和挥发性有机化合物(VOCs)。
    方法:利用液相色谱-质谱(LC-MS)分析MTC和PSC的NVOCs。分别使用电子舌(E-t舌)和电子鼻(E-nose)分析其味道和气味。采用气相色谱-离子迁移谱(GC-IMS)技术对VOCs进行分析。最后,进行了多变量统计分析,以进一步研究MTC和PSC之间的差异,包括主成分分析,正交偏最小二乘判别分析,判别式因子分析,类分析的软独立建模。
    结果:这项研究的结果表明,LC-MS的综合策略,电子舌,电子鼻,GC-IMS,多变量统计分析可以有效地区分MTC和PSC。使用LC-MS,在MTC中鉴定出25种NVOCs,而在PSC中鉴定出18种NVOCs。MTC中的主要化合物是类固醇,而PSC中的主要化合物是环烯醚萜苷。同样,E舌准确揭示了MTC和PSC之间明显的味觉差异。具体来说,PSC中明显的苦味被证明是源于环烯醚萜苷,而MTC中明显的苦味与类固醇密切相关。电子鼻在MTC中检测到八种气味成分,在PSC中检测到六种气味成分,分别。随后的统计分析揭示了它们的气味特征的显著差异。GC-IMS提供了MTC和PSC之间VOC差异的视觉表示。结果表明,MTC中82种VOCs的相对含量相对较高,与PSC中表现出类似高相对含量的32种VOC形成对比。
    结论:在这项研究中,第一次,联合使用LC-MS,电子舌,电子鼻,GC-IMS,和多元统计分析已被证明是从多个角度区分MTC和PSC的有效方法。该方法为其他视觉相似中药的鉴别提供了有价值的参考。
    BACKGROUND: Marsdeniae tenacissimae Caulis (MTC), a popular traditional Chinese medicine, has been widely used in the treatment of tumor diseases. Paederiae scandens Caulis (PSC), which is similar in appearance to MTC, is a common counterfeit product. It is difficult for traditional methods to effectively distinguish between MTC and PSC. Therefore, there is an urgent need for a rapid and accurate method to identify MTC and PSC.
    OBJECTIVE: The aim is to distinguish between MTC and PSC by analyzing the differences in nonvolatile organic compounds (NVOCs), taste, odor, and volatile organic compounds (VOCs).
    METHODS: Liquid chromatography-mass spectrometry (LC-MS) was utilized to analyze the NVOCs of MTC and PSC. Electronic tongue (E-tongue) and electronic nose (E-nose) were used to analyze their taste and odor respectively. Gas chromatography-ion mobility spectrometry (GC-IMS) was applied to analyze VOCs. Finally, multivariate statistical analyses were conducted to further investigate the differences between MTC and PSC, including principal component analysis, orthogonal partial least squares discriminant analysis, discriminant factor analysis, and soft independent modeling of class analysis.
    RESULTS: The results of this study indicate that the integrated strategy of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis can be effectively applied to distinguish between MTC and PSC. Using LC-MS, 25 NVOCs were identified in MTC, while 18 NVOCs were identified in PSC. The major compounds in MTC are steroids, while the major compounds in PSC are iridoid glycosides. Similarly, the distinct taste difference between MTC and PSC was precisely revealed by the E-tongue. Specifically, the pronounced bitterness in PSC was proven to stem from iridoid glycosides, whereas the bitterness evident in MTC was intimately tied to steroids. The E-nose detected eight odor components in MTC and six in PSC, respectively. The subsequent statistical analysis uncovered notable differences in their odor profiles. GC-IMS provided a visual representation of the differences in VOCs between MTC and PSC. The results indicated a relatively high relative content of 82 VOCs in MTC, contrasted with 32 VOCs exhibiting a similarly high relative content in PSC.
    CONCLUSIONS: In this study, for the first time, the combined use of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis has proven to be an effective method for distinguishing between MTC and PSC from multiple perspectives. This approach provides a valuable reference for the identification of other visually similar traditional Chinese medicines.
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  • 文章类型: Journal Article
    准确测量复杂样品的成分是日常生活中使用的一系列产品的安全性和有效性的关键,样品制备是此工作流程中的关键步骤。QuEChERS就是这样一种方法,然而,公布的协议没有明确解决酸性问题,基本的,中性,和两亲性物种在一个单一的方案,并经常使用额外的步骤或替代准备来恢复化学类型的广度。我们的工作通过研究QuEChERS用于监测环境固体和血浆中的广泛化学物质的使用来满足这一需求。使用可以容纳毫升和微升样品体积的方案。虽然已发布的方法可能需要大量的资源和时间,我们的方法减少了制备时间(对于环境样品),与“micro-QuEChERS”协议提供了进一步降低成本。使用反相LC-MS评估了这些方法的分析性能,并显示出良好的准确性,精度,和灵敏度的预期浓度在测试的应用。从土壤中提取并分离了亲油性/酸度可变的目标分析物,具有基本上可重复的基体效应<15%RSD和39-100%的回收率。使用“micro-QuEChERS”协议进行的初步“概念验证”调查显示,土壤的基质增强(中值为90%ME)降低,并改善基质效应和血浆回收率(>65%)。因此,这种新颖的样品制备方法可以提供一种改进的方法,该方法具有更广泛的适用性,比其他用于高通量临床分析的方法提供“更清洁”的提取物。
    Accurate measurement of the composition of complex samples is key for the safety and efficacy of a range of products used in daily life, with sample preparation a critical step in this workflow. QuEChERS is one such method, however published protocols do not explicitly address acidic, basic, neutral, and amphiphilic species in a single protocol and often use extra steps or an alternative preparation to recover the breadth of chemical types. Our work addresses this need by investigating the use of QuEChERS for monitoring this wide range of chemistries within environmental solids and blood plasma, using a protocol that can accommodate both milliliter and microliter sample volumes. While published methods can require significant resource and time, our approach offers a reduction in preparation time (for environmental samples), with the \"micro-QuEChERS\" protocol offering a further reduction in cost. The analytical performance of these methods were assessed using reversed-phase LC-MS and showed good accuracy, precision, and sensitivity for the expected concentrations in the tested applications. Target analytes of variable lipophilicity/acidity were extracted and isolated from soil, with largely repeatable matrix effects < 15%RSD and recoveries of 39-100%. An initial \"proof-of-concept\" investigation using the \"micro-QuEChERS\" protocol showed reduced matrix enhancement (median value of 90%ME) for soil, and improved matrix effects and recovery (>65%) for blood plasma. This novel sample preparation method can therefore offer an improved approach with wider applicability providing \"cleaner\" extracts than other methods used for high-throughput clinical analysis.
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  • 文章类型: Journal Article
    先天性代谢错误(IEM)是一组由代谢途径中断引起的疾病,这导致了积累,循环水平降低,或由于潜在的遗传缺陷而导致的代谢物排泄增加。这些异质性的疾病群体在全世界造成大量的新生儿和婴儿死亡率,由于缺乏意识和标准的预防策略,如新生儿筛查(NBS),这是印度等发展中国家最关注的问题。虽然IEM的预测累积发生率据说是~1:800新生儿,在印度人口的背景下,没有与单个IEM的真实患病率有关的数据。需要进行大规模的基于人群的研究,以清楚地了解不同IEM的流行情况。筛选IEM的最佳方法之一是应用先进的液相色谱-质谱(LC-MS)技术,使用定量代谢组学方法,例如选择或多反应监测(SRM或MRM)。基于LC-MS/MRM的新生儿标记代谢物定量的最新进展为从微小体积的生物流体中同时筛查多种疾病开辟了新的机会。在这篇评论文章中,我们强调了基于LC-MS/MRM的代谢组学方法及其高灵敏度和诊断能力如何通过NBS计划对国家公共卫生产生影响.
    Inborn errors of metabolism (IEMs) are a group of disorders caused by disruption of metabolic pathways, which leads to accumulation, decreased circulating levels, or increased excretion of metabolites as a consequence of the underlying genetic defects. These heterogeneous groups of disorders cause significant neonatal and infant mortality across the whole world and it is of utmost concern for developing countries like India owing to lack of awareness and standard preventive strategies like newborn screening (NBS). Though the predictive cumulative incidence of IEMs is said to be ∼1:800 newborns, data pertaining to the true prevalence of individual IEMs is not available in the context of Indian population. There is a need for a large population-based study to get a clear picture of the prevalence of different IEMs. One of the best ways to screen for IEMs is by applying advanced liquid chromatography-mass spectrometry (LC-MS) technology using a quantitative metabolomics approaches such as selected or multiple reaction monitoring (SRM or MRM). Recent developments in LC-MS/MRM based quantification of marker metabolites in newborns have opened a novel opportunity to screen multiple disorders simultaneously from a minuscule volume of biological fluids. In this review article, we have highlighted how LC-MS/MRM based metabolomics approach with its high sensitivity and diagnostic capability can make an impact on the nation\'s public health through NBS programs.
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  • 文章类型: Journal Article
    目的:人类绒毛膜促性腺激素(hCG)治疗缺乏促性腺激素的不育男性使用尿(uhCG)或重组(rhCG)来源的hCG,但是这些治疗方法尚未进行比较,也没有研究定义rhCG在男性中的剂量。
    方法:hCG产品在标准的随机交叉单剂量研究中进行了研究(研究1,1500IU和62.5µg,分别)或高(研究2,5000IU和250µg)剂量和hCG使用的多剂量人群药理学研究。
    方法:8名(研究1)和7名(研究2)交叉志愿者和52名促性腺激素缺乏的男性在多剂量研究中测量:在交叉研究中,血清睾酮(T),双氢睾酮(DHT)和雌二醇通过液相色谱-质谱(LCMS)和血清hCG,LH,FSH,通过免疫测定的SHBG和T(观察性研究)。
    结果:在标准和高剂量注射后,血清hCG和睾酮反应具有相似的时间和峰值浓度,除了早期(<48h)血清睾酮与uhCG轻度降低.在多剂量研究中,两种hCG具有相似的药代动力学(合并半衰期5.8天,p<.001),而注射后血清睾酮浓度稳定,不同hCG产品之间没有差异。台架测试验证了来自4/10个体的20%的笔被不适当地使用。
    结论:尽管hCG的药代动力学在形式上不是生物等效的,对血清睾酮的相似药效学效应表明,在所测试的剂量下,两种hCG提供了相当的临床效果.用于治疗促性腺激素缺乏的男性的rhCG的起始剂量应为rhCG笔的62.5µg(6次点击)。
    OBJECTIVE: Human choriogonadotrophin (hCG) treatment of gonadotrophin-deficient infertile men uses hCG of urinary (uhCG) or recombinant (rhCG) origin, but these treatments have not been compared nor are there studies defining rhCG dosing in men.
    METHODS: hCG products were studied in randomized cross-over single-dose studies of standard (Study 1, 1500 IU and 62.5 µg, respectively) or high (Study 2, 5000 IU and 250 µg) dose and a multi-dose population pharmacology study of hCG use.
    METHODS: Eight (Study 1) and seven (Study 2) volunteers in cross-over and 52 gonadotrophin-deficient men in the multi-dose study MEASUREMENTS: In cross-over studies, serum testosterone (T), dihydrotestosterone (DHT) and estradiol by liquid chromatography-mass spectrometry (LCMS) and serum hCG, LH, FSH, SHBG and T (observational study) by immunoassays.
    RESULTS: After standard and high-dose injection, serum hCG and testosterone responses had similar timing and peak concentrations except for a mildly lower early (<48 h) serum testosterone with uhCG. In the multi-dosing study, both hCGs had similar pharmacokinetics (pooled half-life 5.8 days, p < .001), while serum testosterone concentrations were stable after injection and did not differ between hCG products. Bench testing verified that 20% of pens from 4/10 individuals were used inappropriately.
    CONCLUSIONS: Although hCG pharmacokinetics are not formally bioequivalent, the similar pharmacodynamic effects on serum testosterone indicate that at the doses tested both hCGs provide comparable clinical effects. The starting dose of rhCG for treating gonadotrophin-deficient men should be 62.5 µg (6 clicks) of the rhCG pen.
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  • 文章类型: Journal Article
    花生和葡萄干中四种黄曲霉毒素B1,B2,G1和G2的同时定量的优化和验证在超高效液相色谱上结合荧光检测器,没有衍生化。优点是分析时间短,简单的样品处理,减少溶剂消耗。AFB1、AFB2、AFG1和AFG2的仪器检出限分别为0.07、0.01、0.1和0.008μg/kg,分别,低于LCMSMS和衍生化HPLC-FLD获得的。为两种不同的基质选择了两种溶剂混合物,其基质效应不可忽略(花生为2.81%-8.04%,葡萄干为5.63%-11.43%)。AFB1和AFG1的线性范围为0.2至20μg/L,AFB2和AFG2的线性范围为0.05至5μg/L。花生和葡萄干的检出限和定量限为0.025-0.1和0.075-0.3μg/kg,分别。在SANTE11312/2021之后,在其他三个浓度下从0.75至125μg/kg的总黄曲霉毒素的回收率在76.5%至99.8%之间(RSD<6%)。验证参数符合ISO/IEC17025:2017的要求。提取物和样品可以在4°C和20°C下稳定24小时,在-20°C下稳定长达21天,分别。因此,该研究可用作分析花生和葡萄干基质中黄曲霉毒素(AFs)的标准方法。对在HCM市中心区市场收集的350份花生样品的调查显示,28.6%的人被AFB1污染,从0.31到554μg/kg;13.4%的人含有AFB2,5.7%的AFG1在0.4-53μg/kg和0.4-9.57μg/kg的范围内,分别检测到0.45至0.75μg/kg的AFG2(约0.6%)。同时,12.8%超过了黄曲霉毒素总量限值,13.4%超过AFB1限值。在350个葡萄干样品中几乎没有发现AF。
    Optimization and validation for simultaneous quantitation of four aflatoxins B1, B2, G1, and G2 in peanuts and raisins were performed on ultra-performance liquid chromatography in a combination of fluorescence detector, without derivatization. The advantages were short analysis time, simple sample handling, and reduced solvent consumption. Instrument detection limits of AFB1, AFB2, AFG1, and AFG2 were 0.07, 0.01, 0.1, and 0.008 μg/kg, respectively, lower than those obtained by LCMSMS and HPLC-FLD with derivatization. Two solvent mixtures were chosen for two different matrices whose matrix effect was not negligible (2.81%-8.04% for peanuts and 5.63%-11.43% for raisins). The linear ranges were from 0.2 to 20 μg/L for AFB1 and AFG1 and from 0.05 to 5 μg/L for AFB2 and AFG2. The limits of detection and quantification were 0.025-0.1 and 0.075-0.3 μg/kg for peanuts and raisins, respectively. Recoveries at three other concentrations from 0.75 to 125 μg/kg of total aflatoxins were obtained between 76.5% and 99.8% (with RSD < 6%) following the SANTE 11312/2021. Validation parameters complied with the requirements of ISO/IEC 17025:2017. The extracts and the sample could be stabilized at 4°C and 20°C for 24 h and at -20°C for up to 21 days, respectively. Thus, the study can be used as a standard method for the analysis of Aflatoxins (AFs) in peanut and raisin matrices. Investigation of 350 peanut samples collected at Markets in the central districts of HCM city showed that 28.6% were contaminated with AFB1 from 0.31 up to 554 μg/kg; 13.4% contained AFB2, and 5.7% of AFG1 in the range of 0.4-53 μg/kg and 0.4-9.57 μg/kg, respectively; AFG2 (about 0.6%) was detected from 0.45 to 0.75 μg/kg. Meanwhile, 12.8% exceeded the total aflatoxins limit, and 13.4% exceeded the AFB1 limit. AFs were almost not found in the 350 raisin samples.
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  • 文章类型: Journal Article
    椎间盘退变是与年龄有关的病症。它还伴随着脊索细胞的消失,是髓核(NP)发育阶段的残留物。分子变化,如细胞外基质分解代谢,细胞表型,和糖胺聚糖在NP中的损失已经被广泛研究。然而,作为最重要的共翻译和翻译后修饰之一,糖基化在变性细胞中被忽视。这里,我们旨在表征年轻和成熟NP的N-糖,并确定与衰老相关的模式。因此,我们从猪圆盘中的富含脊索细胞的NP中分离出N-聚糖,使用外切糖苷酶消化和亲水相互作用超高效液相色谱和质谱分析的组合方法对它们进行了表征。我们为每个年龄组分配了300多个单独的N-聚糖。此外,我们观察到大量的触角结构,半乳糖基化,岩藻糖基化,两个年龄组的唾液酸化。此外,正如我们的结果表明,随着年龄的增长,外臂岩藻糖基化增加和α(2,3)相关唾液酸化减少表明这些性状与年龄有关。最后,我们已经集中在一个广泛的表征的N-糖的丰富的细胞NP老化没有推断变性,仅描述特定于衰老的糖基化变化。我们的发现与其他研究相结合,表明NP的变性不涉及与衰老相同的过程。
    Degeneration of the intervertebral disc is an age-related condition. It also accompanies the disappearance of the notochordal cells, which are remnants of the developmental stages of the nucleus pulposus (NP). Molecular changes such as extracellular matrix catabolism, cellular phenotype, and glycosaminoglycan loss in the NP have been extensively studied. However, as one of the most significant co- and posttranslational modifications, glycosylation has been overlooked in cells in degeneration. Here, we aim to characterize the N-glycome of young and mature NP and identify patterns related to aging. Accordingly, we isolated N-glycans from notochordal cell-rich NP from porcine discs, characterized them using a combined approach of exoglycosidase digestions and analysis with hydrophilic interaction ultra-performance liquid chromatography and mass spectrometry. We have assigned over 300 individual N-glycans for each age group. Moreover, we observed a notable abundance of antennary structures, galactosylation, fucosylation, and sialylation in both age groups. In addition, as indicated from our results, increasing outer arm fucosylation and decreasing α(2,3)-linked sialylation with aging suggest that these traits are age-dependent. Lastly, we have focused on an extensive characterization of the N-glycome of the notochordal cell-rich NP in aging without inferred degeneration, describing glycosylation changes specific for aging only. Our findings in combination with those of other studies, suggest that the degeneration of the NP does not involve identical processes as aging.
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  • 文章类型: Comparative Study
    BACKGROUND: Thymosin beta-4 (TB4) is an X-linked gene product with cardioprotective properties. Little is known about plasma concentration of TB4 in heart failure (HF), and its relationship with other cardiovascular biomarkers. We sought to evaluate circulating TB4 in HF patients with preserved (HFpEF) or reduced (HFrEF) ejection fraction compared to non-HF controls.
    RESULTS: TB4 was measured using a liquid chromatography and mass spectrometry assay in age- and sex-matched HFpEF (n=219), HFrEF (n=219) patients, and controls (n=219) from a prospective nationwide study. Additionally, a 92-marker multiplex proximity extension assay was measured to identify biomarker covariates. Compared with controls, plasma TB4 was elevated in HFpEF (985 [421-1723] ng/mL versus 1401 [720-2379] ng/mL, P<0.001), but not in HFrEF (1106 [556-1955] ng/mL, P=0.642). Stratifying by sex, only women (1623 [1040-2625] ng/mL versus 942 [386-1891] ng/mL, P<0.001), but not men (1238.5 [586-1967] ng/mL versus 1004 [451-1538] ng/mL, P=1.0), had significantly elevated TB4 in the setting of HFpEF. Adjusted for New York Heart Association class, N-terminal pro B-type natriuretic peptide, age, and myocardial infarction, hazard ratio to all-cause mortality is significantly higher in women with elevated TB4 (1.668, P=0.036), but not in men (0.791, P=0.456) with HF. TB4 is strongly correlated with a cluster of 7 markers from the proximity extension assay panel, which are either X-linked, regulated by sex hormones, or involved with NF-κB signaling.
    CONCLUSIONS: We show that plasma TB4 is elevated in women with HFpEF and has prognostic information. Because TB4 can preserve EF in animal studies of cardiac injury, the relation of endogenous, circulating TB4 to X chromosome biology and differential outcomes in female heart disease warrants further study.
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  • 文章类型: Review
    代谢组学分析可以揭示生物体代谢组与其表型状态的其他方面之间的关联,对许多生命科学研究人员来说,这是一个有吸引力的前景。代谢组学方法已经在一些地方被采用,但不是很多,昆虫研究系统,从1990年开始评估寄生虫对蛾幼虫的代谢作用。代谢组学现已应用于昆虫生物学的各个方面,包括行为,感染,温度应激反应,CO2镇静剂,和细菌-昆虫共生。从技术和报告的角度来看,这些研究采用了一系列利用既定实验方法的方法。这里,我们回顾了当前的文献,并评估了昆虫学家通常使用的代谢组学方法。我们建议可以在几个方面进行改进,包括抽样程序,采样和设备变化的减少,样品提取物的使用,统计分析,确认,和代谢物鉴定。总的来说,很明显,代谢组学可以识别表型状态和以前的潜在细胞代谢之间的相关性,更有针对性,方法是无法测量的。无针对性的全球分析与高分辨率定量分析的独特组合导致了一种具有未来昆虫学研究潜力的工具。
    Metabolomic analyses can reveal associations between an organism\'s metabolome and further aspects of its phenotypic state, an attractive prospect for many life-sciences researchers. The metabolomic approach has been employed in some, but not many, insect study systems, starting in 1990 with the evaluation of the metabolic effects of parasitism on moth larvae. Metabolomics has now been applied to a variety of aspects of insect biology, including behaviour, infection, temperature stress responses, CO 2 sedation, and bacteria-insect symbiosis. From a technical and reporting standpoint, these studies have adopted a range of approaches utilising established experimental methodologies. Here, we review current literature and evaluate the metabolomic approaches typically utilised by entomologists. We suggest that improvements can be made in several areas, including sampling procedures, the reduction in sampling and equipment variation, the use of sample extracts, statistical analyses, confirmation, and metabolite identification. Overall, it is clear that metabolomics can identify correlations between phenotypic states and underlying cellular metabolism that previous, more targeted, approaches are incapable of measuring. The unique combination of untargeted global analyses with high-resolution quantitative analyses results in a tool with great potential for future entomological investigations.
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