二亚油酰磷脂酰胆碱分析

通过HPLC/HPLC-MS研究了二亚油酰磷脂酰胆碱的测定方法,磷脂样品首先经过HPLC分离得到磷脂酰胆碱,该磷脂酰胆碱再进一步通过不同的HPLC系统分离二亚油酰磷脂酰胆碱,并通过标准样品和质谱进行二亚油酰磷脂酰胆碱的定性.定量方法通过标准样品外标法定量,由方法的回收率和精密度试验可知,该方法已用来测定一般磷脂样品和磷脂酰胆碱样品中的二亚油酰磷脂酰胆碱含量.     

HPLC-RI法快速准确测定大豆磷脂酰胆碱含量

用HPLC -RI法和HPLC -UV法对大豆卵磷脂样品中的磷脂酰胆碱含量进行分析 ,并与二维TLC -P法(AOCSJa7-86)作比较。以WatersSpherisorbS5W(5μmSilica)4.6×250mm硅胶柱为固定相 ,正己烷 -异丙醇 -水 (体积比1∶4∶1)为流动相。色谱条件 :流速0.8mL·min -1,进样量10μL,柱温35℃ ,RI检测器温度35℃。由外标法得出其中磷脂酰胆碱的含量 ,分别采用大豆磷脂酰胆碱标样和蛋黄磷脂酰胆碱标样作为外标物。结果表明HPLC -RI法受标样来源影响小 ,分析结果准确 ,分析过程简便、快速 ,适合作为常规分析方法     

熊胆中磷脂类化合物的等梯度高效液相色谱法分离分析

摘要：建立了测定熊胆中3种主要磷脂组分即磷脂酰胆碱（PC）、磷脂酰肌醇（PI）、磷脂酰乙醇胺（PE）的高效液相色谱法。将熊胆风干后研成粉末,经V（氯仿）:V（甲醇）=1:4提取液处理后,在P-ESilica柱上进行HPLC分析。流动相为V（乙腈）:V（甲醇）=76:24,流速1.5mL/min,紫外检测波长205nm。PC的平均回收率为89.30％,相对标准差RSD=2.0％。在精密度实验中,PI,PC,PE保留时间的RSD分别为3.9％,1.2％,1.9％,峰面积的RSD分别为1.6％,0.89％,2.     

乳化萃取技术抽提大豆磷脂中的磷脂酰胆碱

利用乳化萃取设备，乙醇为溶剂，进行固液抽提于大豆磷脂中制备磷脂酰胆碱。通过正交实验得出优化的分离条件为：抽提时间10min；抽提温度-10℃；磷脂／乙醇比25g／300mL；乙醇浓度95％。HPLC分析结果表明：抽提后产品中磷脂酰胆碱的含量可以从原料中的18．9％提高到69．6％。     

直接进样电喷雾串联质谱法测定草鱼肌肉组织中磷脂

建立了直接进样电喷雾串联质谱测定草鱼肌肉组织中磷脂的方法.以Bligh Dyer法提取总脂质,采用流动注射泵直接进样的方式将样品导人电喷雾离子源,利用串联三重四级杆质谱的母离子扫描和中性丢失扫描功能,通过扫描磷脂的特征性子离子或中性质量丢失实现对磷脂酰胆碱、磷脂酰乙醇胺、磷脂酰肌醇、磷脂酰丝氨酸、磷脂酰甘油和磷脂酸六类磷脂的源内分离和鉴定.结果显示,在-定的浓度范围内,磷脂的浓度与磷脂直接进样电喷雾电离后形成准分子离子的响应值呈现良好的线性关系,回收率(67.1％～96.6％)和精密度可以满足生物样品分析的要求.采用本方法测定了草鱼肌肉组织中磷脂酰胆碱、磷脂酰乙醇胺、磷脂酰肌醇和磷脂酰丝氨酸4类磷脂的分子种及含量.本方法前处理简单,定性和定量分析快速准确,可以应用于其它生物样本脂质组学中磷脂的分析.     

高效液相色谱法分析大豆中磷脂酰胆碱的分子种

用高效液相色谱法（HPLC）在正相半制备硅胶柱上将大豆磷脂酰胆碱与其它组分分离，从柱后收集磷脂酰胆碱（PC），然后在反相C18柱上分析其分子种组成，蒸发光散射检测器检测。在25min内将大豆磷脂酰胆碱分离成11个分子种组分，使用易挥发溶剂，可获得各种分子种的纯物质，供进一步分析。分子种根据HPLC峰的脂肪酸组成分析而确定。     

磷脂酰胆碱水溶液CMC的测定

磷脂酰胆碱水溶液ＣＭＣ的测定陈鲁生周武姜云生（山东师范大学化学系济南２５００１４）关键词磷脂酰胆碱临界胶束浓度磷脂酰胆碱是一种天然生物两性表面活性物质，也是一种重要的生命物质，具有广泛的用途［１］，由于磷脂酰胆碱的水溶性较差，所以较长时间以来对其溶液...     

含芳基磷脂酰胆碱类似物的合成

磷胆酰胆碱;磷脂类似物;酰化;含芳基磷脂酰胆碱类似物的合成     

液相色谱-质谱用于卵巢肿瘤中磷脂轮廓的分析

卵巢肿瘤日益影响女性的健康和生活质量,其中的卵巢癌是女性三大恶性肿瘤之一,死亡率高居三者之首。因此卵巢肿瘤尤其卵巢癌是目前的一个研究热点。本研究利用液相色谱-质谱(LC-MS)联用技术对卵巢肿瘤进行磷脂轮廓分析,研究良性卵巢肿瘤(B)和卵巢癌(M)的患者血清中磷脂代谢的差异情况。首先用LC-MS采集血清中磷脂的指纹图谱,通过峰识别、峰匹配等得到峰表,然后利用正交校正的偏最小二乘法(OSC-PLS)进行多种分型,根据模型的变量重要因子(VIP)、VIP值的置信区间、S图和显著性差异检验结果等筛选有差异的磷脂。结果显示: M组和B组与正常对照(N)组比较都存在明显的磷脂代谢差异,发生改变的磷脂主要为缩醛磷脂酰乙醇胺、磷脂酰胆碱、缩醛磷脂酰胆碱、鞘磷脂和溶血磷脂酰胆碱。     

高效液相色谱-蒸发光散射检测法测定蛋黄卵磷脂的含量

建立了蛋黄磷脂中卵磷脂（即磷脂酰胆碱,PC)的高效液相色谱-蒸发光散射检测（HPLC-ELSD）的测定方法。以Nov a-Pak Silica 60A硅胶柱(3.9 mm i.d.×150 mm,4 μm)为分离柱,正己烷-异丙醇-3%冰醋酸水溶液(体积比为35∶65 ∶8)为流动相，等度洗脱,流速1.0 mL/min,柱温30 ℃。蒸发光散射检测器漂移管温度50 ℃,雾化气(空气)压力350 kPa。在上述条件下测得PC在0.16~1.61 g/L范围内线性关系良好(r2=0.9979),检测限为0.64 μg,方法的精密度为3.2%(n=5),回收率为98.2%~128.2%。将该方法用于实际样品的测定,获得了令人满意的结果。该方 法预处理简单,分析速度快,可用于蛋黄磷脂中卵磷脂的测定。     

Analysis of Phospholipids in Crucian Carp(Carassius auratus) Muscle by Offline HPLC-MALDI-TOF MS

The interest in the analysis of phospholipids(PLs), especially phosphatidylcholine(PC), has been increasing due to the importance of them in biochemistry as well as in industry. A method was reported based on the offline combination of MALDI-TOF MS and normal-phase HPLC for analyzing PLs extracted from crucian carp. Total PLs of crucian carp were extracted and then separated by HPLC before the collected subfractions were analyzed by MALDI-TOF MS. The mass spectra obtained show peaks of H+, Na+ and K+ adduct...     

A direct and simple method of coupling matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) to thin-layer chromatography (TLC) for the analysis of phospholipids from egg yolk

Although the most important application of matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) is "proteomics," there is growing evidence that this soft ionization method is also useful for phospholipid (PL) analysis. Although all PLs are detectable by MALDI-TOF MS, some lipid classes, particularly those with quaternary amines such as phosphatidylcholines (PCs), are more sensitively detected than others, and these suppress the signals of less sensitively detected PLs when complex mixtures are analyzed. Therefore, a separation of the total organic extract into individual lipid classes is necessary. As MALDI uses a solid sample, the direct evaluation of thin-layer chromatography (TLC) plates is possible. We report here on a method of directly coupling MALDI-TOF MS and TLC that can be easily implemented on commercially available MALDI-TOF devices. A total extract of hen egg yolk is used as a simple PL mixture to demonstrate the capabilities of this method. It will be shown that "clean" spectra without any major contributions from fragmentation products and matrix peaks can be obtained, and that this approach is even sensitive enough to detect the presence of PLs at levels of less than 1% of the total extract.     

Sphingomyelin is more sensitively detectable as a negative ion than phosphatidylcholine: a matrix-assisted laser desorption/ionization time-of-flight mass spectrometric study using 9-aminoacridine (9-AA) as matrix

Phospholipids (PLs) are increasingly analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) and imaging MS. Different classes of PLs are preferentially detectable either as positive or negative ions depending on the charges of their headgroups. Sphingomyelin (SM) and phosphatidylcholine (PC) occur in virtually all biological samples and both are assumed to be detectable with the same sensitivity (in the positive ion mode) because their headgroups are identical. We will show here that the detectabilities of PC and SM depend on the matrix used. In the presence of 2,5-dihydroxybenzoic acid (DHB) SM is more sensitively detectable in positive ion mode than PC while the use of 9-aminoacridine (9-AA) as matrix inverts the detectabilities. Our explanation is that the preferred generation of negative ions from SM if 9-AA is used as matrix results in a reduced yield of positive ions. It will also be shown that this is not only valid if a simplified model system is investigated, but also if, for instance, extracts from human erythrocytes are investigated. It will also be outlined that this finding is particularly important in the context of imaging studies where no previous separation of the lipids of interest can be performed.     

A shotgun tandem mass spectrometric analysis of phospholipids with normal-phase and/or reverse-phase liquid chromatography/electrospray ionization mass spectrometry

Electrospray ionization mass spectrometry is used in lipidomics studies. The present research established a top-down liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) shotgun analysis method for phospholipids (PLs) using a normal-phase column or a C30 reverse-phase column with the data-dependent MS/MS scanning mode. A normal-phase column can separate most of the major different classes of PLs. By using LC/ESI-MS/MS with a normal-phase column, approximately 50 molecular species were identified in a PL mixture from rat liver. When the reverse-phase column was used, the PLs could be separated depending on their hydrophobicity, essentially the length of their fatty acyl chains and the number of unsaturated bonds in them. The LC/ESI-MS/MS method using a C30 reverse-phase column was applied to phosphatidylcholine (PC) and phosphatidylethanolamine (PE) mixtures as test samples. Molecular species with the same molecular mass but with different pairs of fatty acyl chains were separately identified. As a result, about 60 PC and 50 PE species were identified. PLs from rat liver were subjected to LC/ESI-MS/MS using the C30 reverse-phase column and about 110 molecular species were identified. Off-line two-dimensional LC/ESI-MS/MS with the normal-phase and C30 reverse-phase columns allowed more accurate identification of molecular species by using one-dimensional C30 reverse-phase LC/ESI-MS/MS analysis of the collected fractions.     

Separation of polysorbates by liquid chromatography on a HILIC column and identification of peaks by MALDI-TOF MS

Polysorbates can be separated according to their functionality and architecture by liquid chromatography on a hydrophilic interaction chromatography (HILIC) column in acetone–water mobile phases containing 90–97% acetone. The different polymer homologous series are separated according to the number of terminal hydroxy groups and elute as narrow peaks. The hydrophilic part (ethoxylates of sorbitan, isosorbide, and poly(ethyleneglycol)) and amphiphilic funtionalites (ethoxylated mono-, di-, tri-, and tetraesters) were separated by HILIC mode of high-performance liquid chromatography (HPLC). All these separated functionaities are identified and confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). This combination of HPLC and MALDI-TOF MS has been proven to be an excellent tool for the characterization of heterogenous complex samples.     

Efficient and rapid method for extraction of intact phospholipids from sediments combined with molecular structure elucidation using LC–ESI-MS–MS analysis

This paper presents the application of an efficient method for extraction and fractionation of intact phospholipids (PLs) from complex sediment matrices and elucidation of their molecular structure by normal-phase HPLC–ESI-MS–MS. Flow-blending extraction was tested with different solvent mixtures and the best recovery of all PLs classes from the sediment matrix was achieved by using methanol–dichloromethane–buffer, 2:1:0.8. The applied LC–ESI-MS system has linearity of R²=0.98 and a detection limit of 0.5 ng/PL, sufficient for reliable identification of complex mixtures of PLs. MS–MS analyses using a triple-quadrupole mass spectrometer enables detection of individual PL side-chain composition and, hence, characterization of the living organisms contributing to the sedimentary organic material. Parallel GC–MS analysis of the hydrolysed phospholipid fatty acids supports the characterized fatty acid patterns determined from intact PLs. The PL inventory of different investigated lacustrine surface sediments shows predominantly high abundance of phosphatidylglycerols and phosphatidylethanolamines and phosphatidyl-mono- and dimethyl-ethanolamines with fatty acyl side-chains typically known from bacteria. In a sample from Lake Baikal intense signals of bacterial 14:0-acyl-PGs were also identified, for the first time in sediments as far as we are aware.     

Sample handling and contamination encountered when coupling offline normal phase high performance liquid chromatography fraction collection of petroleum samples to Fourier transform ion cyclotron resonance mass spectrometry

Normal phase high performance liquid chromatography (HPLC) is used to separate a gas oil petroleum sample, and the fractions are collected offline and analyzed on a high resolution Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FT-ICR MS). The separation prior to MS analysis dilutes the sample significantly; therefore the fractions need to be prepared properly to achieve the best signal possible. The methods used to prepare the HPLC fractions for MS analysis are described, with emphasis placed on increasing the concentration of analyte species. The dilution effect also means that contamination in the MS spectra needs to be minimized. The contamination from molecular sieves, plastics, soap, etc. and interferences encountered during the offline fraction collection process are described and eliminated. A previously unreported MS contamination of iron formate clusters with a 0.8 mass defect in positive mode electrospray is also described. This interference resulted from the stainless steel tubing in the HPLC system. Contamination resulting from what has tentatively been assigned as palmitoylglycerol and stearoylglycerol was also observed; these compounds have not previously been reported as contaminant peaks.     

Thin-layer chromatography combined with MALDI-TOF-MS and 31P-NMR to study possible selective bindings of phospholipids to silica gel

High-performance thin-layer chromatography (HPTLC) is a highly established separation method in the field of lipid and (particularly) phospholipid (PL) research. HPTLC is not only used to identify certain lipids in a mixture but also to isolate lipids (preparative TLC). To do this, the lipids are separated and subsequently re-eluted from the silica gel. Unfortunately, it is not yet known whether all PLs are eluted to the same extent or whether some lipids bind selectively to the silica gel. It is also not known whether differences in the fatty acyl compositions affect the affinities to the stationary phase. We have tried to clarify these questions by using a readily available extract from hen egg yolk as a selected example of a lipid mixture. After separation, the complete lanes or selected spots were eluted from the silica gel and investigated by a combination of MALDI-TOF MS and ³¹P NMR spectroscopy. The data obtained were compared with the composition of the total extract (without HPTLC). Although there were significant, solvent-dependent losses in the amount of each lipid, the relative composition of the mixture remained constant; there were also only very slight changes in the fatty acyl compositions of the individual PL classes. Therefore, lipid isolation by TLC may be used without any risk of major sample alterations.

Simultaneous profiling of lysophospholipids and phospholipids from human plasma by nanoflow liquid chromatography-tandem mass spectrometry

In this study, an analytical method for the simultaneous separation and characterization of various molecular species of lysophospholipids (LPLs) and phospholipids (PLs) is introduced by employing nanoflow liquid chromatography-electrospray ionization tandem mass spectrometry (nLC-ESI-MS/MS). Since LPLs and PLs in human plasma are potential biomarkers for cancer, development of a sophisticated analytical method for the simultaneous profiling of these molecules is important. Standard species of LPLs and PLs were examined to establish a separation condition using a capillary LC column followed by MS scans and data-dependent collision-induced dissociation (CID) analysis for structural identification. With nLC-ESI-MS/MS, regioisomers of each category of LPLs were completely separated and identified with characteristic CID spectra. It was applied to the comprehensive profiling of LPLs and PLs from a human blood plasma sample and yielded identifications of 50 LPLs (each regioisomer pair of 6 lysophosphatidylcholines (LPCs), 7 lysophosphatidylethanolamines (LPEs), 9 lysophosphatidic acid (LPAs), 2 lysophosphatidylglycerols (LPGs), and 1 lysophosphatidylserine (LPS)) and 62 PLs (19 phosphatidylcholines (PCs), 11 phosphatidylethanolamines (PEs), 3 phosphatidylserines (PSs), 16 phosphatidylinositols (PIs), 8 phosphatidylglycerols (PGs), and 5 phosphatidic acids (PAs)).     

反相高效液相色谱/基质辅助激光解吸电离飞行时间质谱 分离鉴定螺蛳血管紧张素转换酶抑制肽

运用反相高效液相色谱(RP-HPLC)对酶解螺蛳腹足肌得到的血管紧张素转换酶(ACE)抑制肽进行两步分离提纯,第一步主要得到8个组分;选取其中活性最高的组分进一步分离,得到2个组分,其中活性较高组分的ACE半抑制浓度为43.5 μmol/L,基本为单一肽组分。对提纯的组分分别使用高效液相色谱/电喷雾离子质谱法(HPLC/ESI-MS)和基质辅助激光解吸电离飞行时间质谱法(MALDI-TOF MS)进行分析,同时结合氨基酸组成分析结果,最终得到的肽链一级结构为Lys-Glu-Ile-Trp(KEIW),符合已知的高活性ACE抑制肽的结构规律。经过对两种方法分析过程的比较,认为ESI-MS可以得到多方面的信息,但无法确定肽的序列;MALDI-TOF MS可以得到精确的二级质谱图(m/z精确至0.0001),从而可以得到确定的肽的序列。