超声提取正相高效液相色谱法测定大豆及大豆油中的磷酸甘油酯

建立了超声提取-固相萃取纯化/正相高效液相色谱测定大豆及大豆油中磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)、磷脂酰肌醇(PI)的方法。考察了提取溶剂、超声功率、超声时间、提取温度及净化方式的影响,并研究了不同色谱固定相对磷酸甘油酯分离效果的影响。优化的实验条件为:以氯仿-甲醇(2∶1,体积比)为提取溶剂,1 500 W功率超声提取30 min;氨基固相萃取柱为纯化小柱;正己烷-异丙醇-1%HAc(8∶8∶1,体积比)为流动相。在该条件下,PC、PE、PI的线性范围分别为0.08～8.00、0.15～15.00、0.30～20.00 g.L-1,定量下限分别为0.021、0.050、0.060 g.L-1,检出限在8～23 mg.L-1之间,其在大豆和大豆油中的回收率为85%～108%。日内与日间精密度分别不大于4.7%和8.6%。     

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.     

基于HPLC-MS技术的黄颡鱼中不同部位脂质成分分析

利用超高效液相色谱-飞行时间质谱技术(UPLC-Q-TOF-MS/MS)分析了黄颡鱼不同部位的脂质成分。采用甲醇-氯仿(1∶1,体积比)对血清、肌肉和肝脏进行脂质成分提取。液相色谱采用C8色谱柱,柱温40℃,流动相A为乙腈-甲醇-异丙醇(1∶1∶1),流动相B为乙腈-水(0.1%甲酸,0.01%氯化锂)。根据高分辨质谱获得精确分子量,推测出元素组成,并结合脂质成分的二级质谱裂解规律,在血清、肌肉和肝脏中共鉴定出85个脂质成分,主要有PC,Lyso-PC,PE,Lyso-PE,PI,PS,DAG,TAG,SM和Cer。在这3个部位中有19个共有脂质成分,包括Lyso-PC 16∶0,9个PC,3个PI,4个TAG和2个SM。此外PS和Lyso-PE仅在肌肉中鉴定出,分别为PS 18∶0/22∶6,Lyso-PE 16∶0和Lyso-PE 18∶1;神经酰胺仅在肝脏中观察到,为Cer(d18∶1/24∶1);而PE和DAG只在肌肉和肝脏中存在,在血清中未发现。该方法操作简单、灵敏、高效,为快速、全面了解黄颡鱼中的脂质分布提供了科学依据。     

跨膜Ca~(2+)梯度通过磷脂酰胆碱调节肌质网Ca~(2+)-ATP酶

将纯化的肌质网Ca~(2+)-ATP酶重组在具有或不具有跨膜Ca~(2+)梯度的脂质体上,研究了磷脂(特别是磷脂酰胆碱)在跨膜Ca~(2+)梯度对肌质网Ca~(2+)-ATP酶功能调节中的作用。结果表明:(1)高浓度的(Ca~(2+)对与不同磷脂保温的去脂Ca~(2+)-ATP酶都产生抑制,但对与PC保温的Ca~(2+)-ATP酶抑制最大。(2)当存在一个正向跨膜Ca~(2+)梯度时(酶活性中心一侧Ca~(2+)浓度较低,类似生理条件),它只对与中性磷脂PC:PE重组的Ca~(2+)-ATP酶产生抑制,且PC:PE(摩尔比)为1:1时,抑制程度最大。如以酸性磷脂PS或PG替代PC则均无明显抑制。(3)比较不同脂肪酸侧链的PC的作用表明,当DOPC或DPPC存在时均有明显抑制作用,而DMPC则几乎不表现抑制作用。(4)若Ca~(2+)梯度逆转,则无论是与酸性磷脂或中性磷脂重组的肌质网Ca~(2+)-ATP酶都会被抑制。     

高效液相色谱测定大鼠肺细胞膜磷脂

磷脂酰胆碱(phosphatidylcholine,PC)和磷脂酰丝氨酸(phosphatidylserine,PS)是膜磷脂家族中的重要成分。它们对细胞膜中蛋白激酶C(proteinkinase C,PKC)的激活有着重要的调节作用,其浓度上的变化对PKC系统产生激活或抑制作用。本工作用高效液相色谱测定了大鼠肺细胞膜中的磷脂含量。     

HPLC与MALDI-TOF MS联用技术分析蛋黄中的磷脂

蛋黄中含有大量磷脂,其中磷脂酰胆碱(PC)和磷脂酰乙醇胺(PE)最为丰富.本研究采用高效液相色谱法(HPLC)与基质辅助激光解吸电离飞行时间质谱(MALDI-TOF MS)联用技术分析了蛋黄中磷脂粗提物.将从蛋黄中提取的多种磷脂通过HPLC预先分离,收集各组分后分别进行MAIDI-TOF MS分析得到比较清晰的质谱图.通过质谱图解析确定了蛋黄中磷脂酰胆碱、神经鞘磷脂(SM)的脂肪酸组成.     

基于超高效液相色谱-高分辨质谱法的油料作物脂质组学分析

针对油料脂质分子众多、结构难识别的难题,采用超高效液相色谱-高分辨质谱对油菜籽、大豆、花生、向日葵籽、玉米5种油料作物中脂质进行分析。使用反相色谱柱ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm,1.7μm)分离脂质,超高效液相色谱-高分辨质谱仪(UPLC-Orbitrap Fusion Mass)正、负离子模式下采集Data Dependent MS~2数据,利用二级质谱碎片特征、精确分子质量、保留时间以及数据库匹配对脂质分子进行定性分析,获得脂质分子的唯一结构式。共鉴定出油料作物中132种脂质分子,包括8种甘油二酯(DG)、5种溶血磷脂酰胆碱(LPC)、2种溶血磷脂酰乙醇胺(LPE)、24种磷脂酰胆碱(PC)、18种磷脂酰乙醇胺(PE)、8种磷脂酰肌醇(PI)、1种磷脂酰甘油(PG)、1种磷脂酰丝氨酸(PS)以及65种甘油三酯(TG),并使用峰面积比进行相对含量的比较。该方法可以很好地实现脂质成分的分离,将油料作物中脂质成分的分析从脂肪酸分析水平提升到脂质分子层面,为更好地实现油料作物中脂质成分的应用提供了研究基础,并促进了脂质组学的发展。     

胆固醇与磷脂酰乙醇胺/磷脂酰胆碱混合膜的热力学特性及其单层膜形态的AFM观察

研究了不同比例下胆固醇(Chol)对磷脂酰乙醇胺/磷脂酰胆碱(PE/PC,1∶1物质的量比)混合膜的影响,并在表面压力-平均分子面积(π-A曲线)等温线基础上,通过对过量平均分子面积(ΔAex)和过量吉布斯自由能(ΔGex)的计算分析,研究了不同比例Chol与PE/PC(1∶1物质的量比)三元混合膜的热力学特性.实验结果表明:Chol在一定程度上加速了混合膜的相变,增强了膜的凝聚性;当XChol=0.2,0.6,0.8时,过量平均分子面积和过量吉布斯自由能在所研究的表面压力下都为负值,分子之间相互作用力表现为引力,促使混合膜的凝聚,而在XChol=0.4时,过量平均分子面积和过量吉布斯自由能在15,20,25,30 mN/m下为正值,分子之间相互作用力表现为斥力,促使熵的增加,并且在20 mN/m压力下出现极值.实验中利用LB膜技术制备了不同比例Chol与PE/PC(1∶1物质的量比)混合膜,并在原子力显微镜下对其结构形态进行了观测.     

固相萃取-高效液相色谱法同时测定克伦特罗和沙丁胺醇

提出用固相萃取 -高效液相色谱法同时测定饲料中微量克伦特罗和沙丁胺醇的新方法。选用 Dikma Diamonsil C18-ODS分析柱 (2 0 0× 4.6mm,5μm) ,乙腈 -0 .0 1mol/ L KH2 PO4 (p H 3 .0 )作流动相 ,应用波长编程进行检测。克伦特罗和沙丁胺醇的线性范围为 0 .1～ 1 0 0μg/ m L,相关系数分别为 0 .99999和 0 .99977,检出限分别为0 .3 1 ng/ m L和 0 .2 4ng/ m L ,回收率分别为 91 .2 %～ 92 .0 %和 91 .9%～ 93 .0 % ,相对标准偏差分别是 1 .2 0 %～ 2 .0 5%和 1 .2 9%～ 2 .51 %。     

母乳中甲硝唑、替硝唑测定及药代动力学

采用高效液相色谱法测定哺乳妇女单剂量静滴甲硝唑 ( 2 0mg/kg ,n =8)、替硝唑 ( 1 3mg/kg ,n =7)乳汁药物浓度 ,色谱柱为 pecoshereC1 8( 3μm ,3.3cm× 4.6mm) ,氯仿提取乳汁中药物 ,其平均回收率大于 88.8% .乳汁中甲硝唑与替硝唑药代动力学参数tmax,Cmax,t1 / 2Ke分别为 1 .7± 1 .0h ,2 0 .1 0± 4.95μg/mL ,6.4± 3.3h和 1 .3±0 .6h ,1 7.2 3± 3.1 2 μg/mL ,1 1 .0± 3.5h .     

用高效液相色谱法测定热应激时大鼠肺及肝组织中细胞膜磷脂的变化

 应用高效液相色谱法（ＨＰＬＣ）测定了正常大鼠肺及肝组织中细胞膜磷脂的含量及热应激时膜磷脂的含量变化。流动相为甲醇∶乙腈∶８５％磷酸（３∶１００∶１，Ｖ／Ｖ／Ｖ），色谱柱为μ－Ｐｏｒａｓｉｌ柱（３．９ｍｍｉ．ｄ．×３００ｍｍ）。通过测定膜磷脂的变化，可以为阐明机体的发病机理提供可靠的数据。     

HPLC analysis of mitochondrial membrane phospholipids in rice

The effects of different columns and mobile phases on the separation of mitochondrial membrane phospholipids in rice by high-performance liquid chromatography (HPLC) were studied. The results suggest that the main six kinds of phospholipids in the rice mitochondrial membrane can be successfully separated within 22 min on a KR 100-SIL (250 × 4.6 mm, 5 μm) column with a mobile phase of acetonitrile-methanol-85% phosphoric acid (100: 10: 0.8, V/V) and DAD detector (205 nm). The quantitative analysis of five important components—phospatidylinositol (PI), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphotidic acid (PA), and phosphatidylcloline (PC)—has been achieved with an external standard method. The linear range is 0.005–2.00 mg/mL, the recovery ratio is 95.9–100.6%, and the relative standard deviation is 0.32–1.24%. The study indicates that the HPLC method that has been applied to the analysis of the trace content of biomembrane phospholipids is characterized by a satisfactory linear relationship, reproducibility, and stability. The text was submitted by the authors in English.     

Sodium ion internalized within phospholipid membranes

Seven phospholipids, modified with ester groups in their hydrophobic chains, were synthesized and examined for their ability to promote sodium ion flux across vesicular membranes. It was found by 23Na NMR that only the phospholipids having short chain segments beyond their terminal ester groups catalyze sodium ion transfer by up to 2 orders of magnitude relative to a conventional phospholipid, POPC. The rates increase with the concentration of the ester-phospholipid admixed with POPC in the bilayer. More surprisingly, the rates increase with the time allowed for the vesicles to age. This was attributed to ester-phospholipid migrating in the bilayers to form domains that solubilize the sodium ion within the hydrocarbon interior of the membrane. Such membrane domains explain why shift reagent-modified NMR spectra display three 23Na signals representing sodium outside the vesicles, sodium within the vesicular water pools, and sodium within the membranes themselves.     

磷脂膜的相行为对氧化石墨烯与磷脂膜相互作用的影响

通过使用不同相变温度的磷脂分子并调节二者的比例构筑了不同相态的磷脂膜, 并利用表面增强红外光谱和激光共聚焦显微镜研究了磷脂膜的相行为对氧化石墨烯和磷脂膜相互作用的影响. 结果表明, 氧化石墨烯对磷脂膜中磷脂分子的抽提作用具有显著的相态选择性, 其选择性地抽提流动相的磷脂分子; 氧化石墨烯对流动相磷脂的抽提作用受到膜中凝胶相磷脂存在比例的影响, 只有在流动相磷脂分子占磷脂膜中磷脂分子的绝大部分时才能够发生抽提作用, 且只有流动相的磷脂分子被抽提.     

顶空气相色谱法测定粉状大豆磷脂中的丙酮残留量

 采用顶空气相色谱法测定大豆磷脂中的丙酮残留量。色谱柱为 2m× 3mmi d 内填GDX 10 3的不锈钢柱 ,柱温为 16 0℃。试验结果的相对标准偏差为 1 2 % ,在 2 5 0 μg/g～ 10 0 μg/g范围内 ,回收率为 98 4%～10 4%。     

Triggered release of molecules across droplet interface bilayer lipid membranes using photopolymerizable lipids

A combination of nonpolymerizable phospholipids (DPPC or DPhPC) and a smaller amount of cross-linking photopolymerizable phospholipids (23:2 DiynePC) is incorporated in an unsupported artificial lipid bilayer formed using the droplet interface bilayer (DIB) approach. The DIB is formed by contacting lipid monolayer-coated aqueous droplets against each other in a dodecane-lipid medium. Cross-linking of the photopolymerizable lipids incorporated in the DIB was obtained by exposure to UV-C radiation (254 nm), resulting in pore formation. The effect of cross-linking on the DIB properties was characterized optically by measuring the diffusion of selectively encapsulated dye molecules (calcein) from one droplet of the DIB to the other droplet. Changes in DIB conductivity due to UV-C exposure were investigated using current-voltage (I-V) measurements. The leakage of dye molecules across the DIB and the increase in DIB conductivity after UV-C exposure indicates the formation of membrane pores. The results indicate that the DIB approach offers a simple and flexible platform for studying phototriggered drug delivery systems in vitro.     

顺二氨二水合铂(Ⅱ)与膜磷脂及膜蛋白相互作用的荧光光谱研究

用Tb~(3+)分别对用和未用顺二氨二水合铂(Ⅱ)(AAP)处理的红细胞膜和磷酰胆碱(PC)脂质体进行荧光滴定,测Tb~(3+)荧光。用AAP滴定红细胞膜,测蛋白质自身荧光变化。用间接Scatchard法求结合参数。表明蛋白质及磷脂均与AAP结合,蛋白质结合能力较强。     

非抑制电导检测离子色谱法测定硅藻培养液中硅酸根

采用戴安阴离子AS23(4 mm×250 mm)分析柱和AG23(4 mm×50 mm)保护柱、恒温电导检测器,建立了测定硅藻培养液中硅酸根(SiO2-3)含量的非抑制电导检测离子色谱法。以4 mmol/L碳酸钠为淋洗液,淋洗液流速1.0 mL/min,进样体积100 μL,采用峰高定量。该法测定SiO2-3的线性范围为0~40 mg/L,检出限为0.017 mg/L,重复测定同一标样的相对标准偏差( RSD,n=7 ) 小于5%,峰面积和峰高的RSD分别为10.9%、4.8%。测定不同生长时期硅藻培养液中的SiO2-3,样品的加标回收率为102%~120%。该法灵敏、准确、简便易行,适用于硅藻培养液中SiO2-3的检测。     

Lipids from Bud Meristem of Larix sibirica

The total lipids were isolated from meristematic bud tissues of Larix sibirica L. and cell membrane complexes. Their group composition was established. The dynamics of seasonal variation were studied. The principal lipids were found to be polar lipids residing in the membranes. Lipids in membranes were largely (up to 75% of the mass) replaced in winter by proteinaceous material. The principal lipids in the membranes were phospholipids.     

Separation and determination of metallocyanide complexes of Fe(II), Ni(II) and Co(III) by ion-interaction chromatography with membrane suppressed conductivity detection applied to analysis of oil refinery streams (sour water)

A separation and determination method for the analysis of cyanometallic complexes of Fe(II), Ni(II) and Co(III) was developed to be applied to the analysis of petroleum refinery streams (sour water). Ion-interaction chromatography was used employing an analytical column IonPac NS1 10 microm and a chromatographic system ICS 2500 equipped with a membrane conductivity suppression ASRS ultra 4mm, both supplied by Dionex Corporation. The mobile phase was composed of 2 mmol l(-1) TBAOH, 1 mmol l(-1) Na(2)CO(3), 0.1 mol l(-1) NaCN and ACN (77:23, v/v), flowing at 0.7 ml min(-1). At the optimized conditions, detection limits estimated by the calibration curve parameters and relative standard deviation were: 0.002 mg CNl(-1) and 3.1% for Fe(CN)(6)(4-); 0.003 mg CNl(-1) and 2.5% for Ni(CN)(4)(2-) and 0.003 mg CNl(-1) and 2.8% for Co(CN)(6)(3-). Sour water samples without any pretreatment (except membrane filtration) from a petroleum refinery in Brazil were analyzed successfully by external calibration method.