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建立了采用二维超高效液相色谱-三重四极杆/复合线性离子阱质谱联用快速测定全血和尿液中鱼藤酮的检测方法。尿液经水等量稀释后直接进样分析;全血用乙腈沉淀除蛋白质,上清液用水稀释后进样分析。样品中的鱼藤酮被Cyclone柱保留并去除大分子杂质,然后再被流动相洗入第1维Kinetex Biphenyl色谱柱(联苯基核壳柱)进行分离,再将含有鱼藤酮的流分切割至第2维Acquity BEH C_8色谱柱上进行分离,采用多离子监测触发的增强子离子(MRM-IDA-EPI)扫描方式检测,溶剂标准外标法定量。全血和尿液中的平均加标回收率分别为84.6%~94.3%和88.4%~95.7%,相对标准偏差为2.6%~7.3%和2.8%~6.8%(n=6),方法的检出限为0.2和0.03μg/L。该方法已成功应用于鱼藤酮中毒样品的检测。  相似文献   
2.
高雯  宋慧鹏  杨华  李萍 《色谱》2017,35(1):121-128
中药的组成复杂,其化学成分的表征和识别一直是中药研究的基础和关键。在线二维液相色谱是基于两种分离模式构建的色谱分析技术,主要包括中心切割二维液相色谱和全二维液相色谱两种模式,因二者具有更高的峰容量而在中药研究中备受青睐。该文对在线二维液相色谱技术的概念和特点进行了讨论,并对二维液相色谱在中药研究中的应用进行了综述,以期为该技术在中药质量控制、物质基础表征、活性成分筛选等研究方面提供一定参考。  相似文献   
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The separation of compounds with similar polarities is challenging. In the present study, five flavone glycosides, including two groups with similar polarities, were obtained from Dracocephalum tanguticum by three high-speed counter-current chromatography modes, including flow rate conversion mode, recycling mode, and heart-cut mode. With flow rate conversion mode, compounds 3 and 4 with similar polarities and compound 5 were separated by high-speed counter-current chromatography with ethyl acetate/methanol/water (5.0% acetic acid) (8:2:10, v/v) system. The flow rate was controlled as: 1.8 mL/min for 0–160 min, 2.2 mL/min for 160–200 min, and 2.5 mL/min for 200–400 min. However, compounds 1 and 2 with similar polarities were not separated due to the similar distributive properties. Then, a recycling and heart-cut mode were introduced to improve the separation efficiency. The heart-cut mode was introduced in the second and third cycles, and compounds 1 and 2 were well separated in the fourth cycle. Consequently, five flavone glycosides, including two groups with similar polarities were obtained and identified as cosmosiin (1), pedaliin (2), quercetin-3-O-rutinoside (3), pedaliin-6''-acetate (4), and sorbifolin-6-O-β-glucopyranoside (5). The current strategy provides a reference for separating compounds with similar polarities from a crude sample.  相似文献   
4.
Dual-mode heart-cutting two-dimensional liquid chromatography (DMHC 2D-LC) was applied to isotope dilution mass spectrometry (IDMS) to reduce the bias in the quantitative analysis of a target analyte present in a limited quantity in human plasma. Based on a Waters I-Class LC system, the DMHC 2D-LC system was operated in one- and two-dimensional modes to facilitate the determination of heart-cutting time and the efficient trapping of the target LC eluate. Experiments to determine the feasibility of coupling with IDMS were performed with triple quadrupole mass spectrometry using folic acid standards and/or 13C5-folic acid. To validate the performance of the DMHC 2D-LC/IDMS system on a complex sample, human plasma was analyzed for folic acid and the result was compared with that obtained using conventional single-column LC. The total run time of the DMHC 2D-LC system was 20 min, the same as that of the single-column LC system. The peak profile of the spiked 13C5-folic acid obtained with single-column LC/MS was affected by matrix effects, but resolved with DMHC 2D-LC/MS, thus improving the accuracy of the analysis. The DMHC 2D-LC/IDMS system showed reliable performance in analyzing the target analyte in human plasma, eliminating matrix effects and saving analysis time.  相似文献   
5.
A simple but effective GC approach to odour evaluation and fraction collection with capillary columns is described. An allglass device splits the column effluent, with one splitter arm going to an FID. For odour evaluation, the other splitter arm is led via teflon tubing to the nose. Off-line heart-cutting is carried out by collecting the split effluent on a glass capillary microtrap, the inner walls of which are coated with OV-101. This allows recovery of nanogram amounts of material. Multipass operation or repeated collection leads to preparative capillary GC for further spectroscopic investigation. These techniques do not involve sophisticated equipment or valves. Applications of this type of smell analysis, heart-cutting and enrichment in the analysis of Rhododendron fragrantissimum essential oil, black pepper essential oil and hop essential oil, illustrating the versatility of the systems, are presented.  相似文献   
6.
A method for separation and identification of peaks in essential oil samples based on rapid repetitive heart-cutting using multidimensional gas chromatography (MDGC)-mass spectrometry (MS) coupled with a cryotrapping interface is described. Lavender essential oil is analyzed by employing repetitive heart-cut intervals of 1.00 and 1.50 min, achieved in a parallel MDGC-MS/GC-FID experiment. The number of peaks that were detected in 1D GC operation above a given response threshold more than tripled when MDGC-MS employing the cryotrapping module method was used. In addition, MDGC-MS enabled detection of peaks that were not individually evident in 1D GC-MS, owing to effective deconvolution in time of previously overlapped peaks in 1D GC. Thus separation using the cryomodulation approach, without recourse to using deconvolution software, was possible. Peaks widths decreased by about 5-7-fold with the described method, peak capacity increased from about 9 per min to 60 per min, and greater sensitivity results. Repeatability of retention times for replicate analyses in the multidimensional mode was better than 0.02% RSD. The present study suggests that the described heart-cutting technique using MDGC-MS can be used for general improvement in separation and identification of volatile compounds.  相似文献   
7.
Owing to increasing demand for Panax notoginseng-based medicines and health products, establishing a fast, simple, and reliable assay to analyze the chemical differences between its root and rhizome is important. Although previous studies showed that the chemical and biological differences between the root and rhizome of P. notoginseng seem to be small, efforts should be taken to investigate such differences to ensure the safety and efficacy of the products. This work describes a holistic approach that combines characteristic fingerprinting using ultra-high performance liquid chromatography-tandem mass spectrometry parent ion scanning with charged aerosol detection and targeted separation by online heart-cutting two-dimensional liquid chromatography, to identify and evaluate characteristic markers allowing differentiation of the root and rhizome. A total of five potential markers chikusetsusaponin L5, ginsenoside Rb2, stipuleanoside R2, malonyl-ginsenoside Rb1, and malonyl-ginsenoside Rd, were identified and confirmed by comparing chromatographic retention time, the accurate mass of molecular weight, and the fragments of secondary MS with the available reference materials. The results showed that all five markers were 2.8–7 times higher in content in the rhizome than in the root.  相似文献   
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