毛细管气相色谱法测定炼厂气中单体烃组分的含量

采用PLOT／Al2O3石英毛细管气相色谱柱和氢火焰离子化检测器，建立了炼厂气中单体烃组分含量测定的毛细管气相色谱法，当炼厂气中单体烃组分的含量大于或等于2．1％时，RSD≤0．95％，当炼厂气中单体烃组分的含量为0．5％－2．1％时，RSD为0．95％－10．0％，当炼厂气中单体烃组分的含量为0．2％－0．5％时，RSD为10．0％－25．0％，该方法对单体烃组分的测定结果与行业标准SH／T0230－92《液化石油气组成测定法》的测定结果基本一致。     

K系数—多波长线性回归吸光光度法同时测定人发中铜铁锌

将双波长K系数吸光光度法与多波长线性回归吸光光度法相结合,提出一种同时测定三组分的方法,即K系数－多波长线性回归吸光光度法,采用OP－5－Br-PADAP为显色体系,控制溶液PH值为5．7,利用此方法对人发中铜、铁、锌同时测定,结果满意,相对标准偏差为0．59％－4．95％,加标加收率为95．0％－105．0％之间。方法具有简便,选择性及灵敏高的优点。     

冠心苏合丸中挥发性组分的分析及主成分冰片的测定

采用同时蒸馏-萃取法提取冠心苏合丸中的挥发性组分,测得两种冠心苏合丸中的挥发性组分含量分别为14％和9．8％。利用GC-MS方法对两种冠心苏合丸所得的挥发性组分进行分析,通过检索NIST98谱图库,并结合标准谱图库和有关文献,从冠心苏合丸的挥发性组分中分别确定出14、19种化学成分,分别占挥发性组分总检出量的97．24％和98．76％。用峰面积归一化法,得出各化学成分在挥发性组分中的相对百分含量。主要挥发性组分是冰片。并采用气相色谱法对冠心苏合丸中冰片的含量进行了测定冰片质量浓度在1．0～5、0mg／mL范围内成良好的线性关系,冰片的平均回收率为98％～106％。     

火焰原子吸收光谱法测定蜂蜜中的钙和锌

报道了用直接消解法处理蜂蜜,在选定光谱条件下,用火争原子吸收分光光度计测定其中的钙和锌,与湿法,干法消解处理的试样相比较,该法操作简单,结果令人满意,加标回收率钙为99－101．9％。锌为98．8％－105％,相对标准偏差钙为4．4％－5．9％,锌为2．1％－3．8％检出限钙为0．138ug.mL^-1,锌为0．084ug.mL^-1。     

碳18键合硅胶桩—流动注射—电感耦合等离子体质谱联用技术及其在海水分析中的应用

建立了碳18键合硅胶柱－流动注射－电感耦合等离子体质谱（C18－FI－ICP／MS）联用系统。对螯合反应的pH,碳18柱的尺寸和填充松紧度,洗脱液中甲醇含量及洗脱液流速等进行了优化选择。联用系统已成功地应用于实际样品的在线富集分离分析。对Cd、Pb、Co、Ni和Zn种元素的检测限（3σ）分别为0．03、0．09、0．1、0．3μg/L,6次测定海水的RSD分别为6．8％、3．4％、1．3％、2．6％、0．5％,标准加入方法的回收率分别为91．3％、95．1％、100．4％、100．3％、95．2％。     

反相高效液相色谱法同时测定食品和多维片中8种水溶性维生素

建立了以0．05mol/L KH2PO4-甲醇为流动相的梯度洗脱反相高效液相色谱同时测定水溶性维生素C,B1,B2,B6,B12,烟酸,烟酰胺和叶酸的分析方法,方法检出限为1．4－0．76ng,用该法测定了奶粉,玉米粉,饮料及复合维生素片中水溶性维生素,相对标准偏差为2．8％－8．8％,加标回收率为74．7％－112．5％。     

佛手挥发油的化学成分

用色谱－质谱－计算机联用法对佛手挥发油的化学成分和相对含量进行了系统分析,得到６７种组分,鉴定出３１个组分,主要组分是柠檬烯（４８．４％）、１－甲基－２－（１－甲乙基）－苯（３０．８％）。     

离子色谱法测定大气总悬浮颗粒物中的F~-,Cl~-,NO_3~-及SO_4~(2-)

介绍了用离子色谱法测定大气总悬浮颗粒物（TSP）中的F~－,Cl~－,NO~-_3及SO~2-_4。对过氯乙烯采样滤膜用去离子水（DIH_2O）作为提取液进行超声波提取。方法的平均回收率分别为F~-98．7％,Cl~-103％,NO~-_3101％及SO~2-_499．8％,相对标准偏差为F~－0．29％,Cl~－0．32％,NO~-_30．30％及SO~2-_40．25％。     

离子色谱法测定大气总悬浮颗粒物中的F~-,Cl~-,NO_3~-及SO_4~(2-)

 介绍了用离子色谱法测定大气总悬浮颗粒物（TSP）中的F~－,Cl~－,NO~-_3及SO~2-_4。对过氯乙烯采样滤膜用去离子水（DIH_2O）作为提取液进行超声波提取。方法的平均回收率分别为F~-98．7％,Cl~-103％,NO~-_3101％及SO~2-_499．8％,相对标准偏差为F~－0．29％,Cl~－0．32％,NO~-_30．30％及SO~2-_40．25％。     

金刚烷合成体系成分的毛细管气相色谱及色谱-质谱法分析

采用毛细管气相色谱及色谱－质谱法分析了两种不同催化剂催化合成笼状烃金刚烷反应体系的各主要组分。给出了测试条件和标准曲线。对于AICI3催化反应体系各组分回收率在98％－101％之间,RSD＜5．0％。对于沸石催化反应体系,各组分回收率在96％－103％之间,RSD＜7．0％。该法定量分析快速、简便、准确。     

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.     

超临界流体色谱法分析大豆磷脂

 采用以CO2 为流动相的超临界流体色谱方法 ,以含 0 0 5 % (体积分数 )三乙胺的乙醇作为改性剂 ,对具有重要生物功能的大豆磷脂组成进行分析 ,获得了大豆磷脂提取物中 6个重要组分的定性结果 ,并讨论了流动相组成、操作温度和压力对分离的影响。对其中有代表意义的磷脂酰胆碱 (PC)进行了外标法定量分析 ,在PC质量浓度为0 0 2 0 g/L～ 0 0 75 g/L时具有较好的线性关系 ,PC加样回收率为 96 7% (n =5 ) ,重现性好。此方法可用于实际样品的分析。     

Detection of related substances in polyene phosphatidyl choline extracted from soybean and in its commercial capsule by comprehensive supercritical fluid chromatography with mass spectrometry compared with HPLC with evaporative light scattering detection

Supercritical fluid chromatography with tandem mass spectrometry was used to comprehensively profile polyene phosphatidyl choline (PPC) extracted from soybean. We achieved an efficient chromatographic analysis using a BEH‐2EP column (3 × 100 mm², 1.7 μm) with a mobile phase consisting of CO₂ and a cosolvent in gradient combination at a flow rate of 1.0 mL/min. The cosolvent consisted of methanol, acetonitrile, and water (containing 10 mM ammonium acetate and 0.2% formic acid). The total single‐run time was 7 min. We used this method to accurately detect ten different phospholipids (PLs) during extraction. The limits of quantification for phosphatidyl choline, lyso‐phosphatidylcholine (LPC), phosphatidic acid (PA), sphingomyelin, phosphatidyl glycerol, phosphatidyl inositol (PI), cholesterol, cardiolipin, phosphatidyl serine, and phosphatidyl ethanolamine (PE) were 20.6, 19.52, 1.21, 2.38, 0.50, 2.28, 54.3, 0.60, 0.65, and 4.85 ng/mL, respectively. However, adopting the high‐performance liquid chromatography with evaporative light scattering detection method issued by the China Food and Drug Administration, only PA, LPC, PE, PI, and PPC could be analyzed accurately, and the limits of quantification were 33.89, 60.5, 30.3, 10.9, and 61.79 μg/mL, respectively. The total single‐run time was at the least 20 min. Consequently, the supercritical fluid chromatography with tandem mass spectrometry method was more suitable for the analysis of related PLs.     

2‐(2‐Aminoethylamino)‐5‐nitropyridine as a basic matrix for negative‐mode matrix‐assisted laser desorption/ionization analysis of phospholipids

Fast and easy analysis of phospholipids (PLs) by matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) has been well demonstrated. However, when using common organic matrices, such as 2,5‐dihydroxybenzoic acid (DHB), the detection of most PL classes in positive‐ion mode is difficult when PLs containing zwitterionic groups, such as phosphatidylcholines (PCs) and sphingomyelins (SMs) are present. To reduce this limitation, 2‐(2‐aminoethyloamino)‐5‐nitropyridine (AAN), a basic compound, was evaluated as an alternative matrix. Negative‐ion spectra showed enhanced detection of phosphatidyl ethanolamines (PEs), phosphatidyl serines (PSs), phosphatidyl glycerols (PGs), and phosphatidyl inositols (PIs) in simple mixtures and in a crude methanolic soybean extract. The relative ionization efficiency (RIE) was highest for PIs and lowest for PGs, PSs, and PEs. Compared to DHB and para‐nitroaniline, AAN resulted in greater sensitivity for the detection of PL classes in the negative mode. Indeed, the S/N ratio was nearly an order of magnitude higher than that reported for similar PI concentrations but with DHB. MALDI spots produced with AAN were homogeneous thus allowing automation and improved reproducibility. Positive‐mode traces could also be acquired with AAN as the matrix, but with lower sensitivity than in the negative mode. Copyright © 2008 John Wiley & Sons, Ltd.     

Micellar electrokinetic chromatography profiles of human high-density lipoprotein phospholipids

A simple and fast micellar electrokinetic chromatography (MEKC) method was developed to investigate phospholipids isolated from human high-density lipoproteins (HDL). To optimize the MEKC conditions, several factors including bile salt concentration and organic modifier concentration in the separation buffer as well as temperature have been examined. The optimal separation buffer chosen was a mixture of 50 mM bile salts, 30% v/v 1-propanol and 10 mM sodium phosphate (pH 8.5). The applied voltage and temperature selected were 25 kV and 40°C, respectively. Meanwhile, high-salt stacking has been performed for sample pre-concentration to enhance peak sensitivity. Several factors including organic modifier concentration and salt concentration in the sample matrix as well as sample injection time have been optimized. The optimal sample buffer selected was a mixture of 100 mM NaCl and 20% 1-propanol, and the optimal sample injection time selected was 32 s under a pressure of 0.5 psi. Several phospholipid standards including lysophosphatidyl choline, phosphatidyl choline (PC), sphingomyelin, phosphatidyl ethanolamine, phosphatidyl inositol, phosphatidyl serine and phosphatidic acid have been studied using the optimal MEKC method. The MEKC profile of the mixed phospholipid standards showed good separation and reproducibility. The linear ranges for PC and sphingomyelin were 0.025-1.2 and 0.025-2.0 mg/mL, respectively. The concentration limits of detection of PC and sphingomyelin were 0.0156 and 0.0199 mg/mL, respectively. Using phosphatidic acid as an internal standard, precision and accuracy have been measured for PC and sphingomyelin. The intraday and interday quantitative analysis showed good results. The new MEKC method has been used to characterize native, in vitro oxidized and glycated human HDL phospholipids within 16 min. At absorbance 200 nm, two similar peaks were observed for native and oxidized HDL phospholipids, but three peaks were observed for glycated HDL phospholipids. Interestingly, at absorbance 234 nm, distinctively different MEKC profiles were observed for the three HDL phospholipids.     

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%。     

A new high-performance liquid chromatographic method with evaporative light scattering detector for the analysis of phospholipids. Application to Iberian pig subcutaneous fat

A new method for the analysis of phospholipids by normal-phase HPLC is described using a silica column. Addition of ammonia and triethylamine to a gradient based on chloroform/methanol/water promoted a good and rapid separation of phospholipid classes (20 min run). The use of an evaporative light scattering detector permitted an accurate analysis of a mixture of phospholipids. Calibration curves were linear within different range for each phospholipid class. The LOD and LOQ obtained were below 0.03 and 0.05 mg kg⁻¹ for all cases, respectively. Besides, a new method for the separation of phospholipids from total lipids before HPLC analysis by a solid-phase extraction (SPE) with Si cartridges has been developed. This methodology gave a good recovery ranging from 97 to 117%. The method was validated with a standard mixture of phospholipids. This method has been applied to characterize the phospholipid fraction of subcutaneous fat from Iberian pig. Cardiolipin, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidylcholine, and sphingomyelin have been described for first time in these samples. The fatty acid composition of the different phospholipid classes and their HPLC electrospray ionization mass spectrometry have been used for characterizing the molecular species present in each one.     

Fenitrothion-induced changes in lipids of rats

The dose-dependent lipid accumulation caused by fenitrothion administration is associated with alteration of the ratio of various components of phospholipids and neutral lipids in various organs of rats up to 48 h. The concentration of triacylglycerol, phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl glycerol increased in liver, kidney and brain in treated rats whereas phosphatidyl serine was greatly reduced. High-performance liquid chromatography and gas-liquid chromatography were used for quantiative analysis of phospholipids and triacylglycerol. The changes in relative composition of various lipids by fenitrothion administration may lead to malfunctioning and alteration of biological properties.     

Estimation of amniotic fluid phospholipids by high-performance liquid chromatography

We have developed a high-performance liquid chromatographic (HPLC) method for the analyses of surface-active amniotic fluid phospholipids, lecithin (L), sphingomyelin (S), phosphatidyl glycerol (PG), phosphatidyl inositol (PI), phosphatidyl ethanolamine (PE), and phosphatidyl serine (PS), which are important in the prediction of fetal lung maturity. The method incorporates an internal standard in the amniotic fluid extract, and utilizes a 10-microliter aliquot of a 2:1 chloroform-methanol extract of amniotic fluid injected onto a 5-micron DIOL or CN HPLC column, and a variable-wavelength detector set at 203 nm. Amniotic fluid phospholipid estimations were determined on 40 amniotic fluid samples by the HPLC method and by the routine thin-layer chromatographic (TLC) method. Good agreement was observed between the two methods for the L/S ratio, PG, and PI (rPG 0.94, rPI 0.95, rL/S 0.97). The advantages of the HPLC procedure include: Selective separation for PG, PI, PS, and PE, as well as L and S at the same time. The internal standard allows individual concentration of phospholipids to be estimated. The procedure is rapid: 16 min for a single assay compared with 50 min for the standard TLC procedure.     

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%。