食用油识别方法的研究

建立了用气相色谱－氢火焰离子检测器（ＧＣ－ＦＩＤ）准确测定了各种食用油中所有脂肪酸含量的方法，提出用脂肪酸含量的分布和相对不饱和度（Ｕ／Ｓ）来识别食用油，识别模型简便可靠，从而达到识别掺假的目的。     

24种安眠镇静药物的气相色谱及气相色谱－质谱系统分析

建立了２４种安眠镇静药物的气相色谱（ＧＣ）及气相色谱－质谱（ＧＣ－ＭＳ）系统分离分析方法。该法在选定的色谱条件下，能将２４种安眠镇静药物很好地分离，互不干扰。采用内标法定量，其线性范围在０～２４μｇ／ｍＬ血，最小检出浓度为０．１～０．４μｇ／ｍＬ血。用所建的ＧＣ方法对１１例中毒病人的生物样品进行分析鉴定，ＧＣ－ＭＳ法验证。从实际中证明所建方法操作简便，准确性和系统性强，灵敏度较高，能快速、准确地为医院的救治提供依据。     

24种安眠镇静药物的气相色谱及气相色谱－质谱系统分析

 建立了２４种安眠镇静药物的气相色谱（ＧＣ）及气相色谱－质谱（ＧＣ－ＭＳ）系统分离分析方法。该法在选定的色谱条件下，能将２４种安眠镇静药物很好地分离，互不干扰。采用内标法定量，其线性范围在０～２４μｇ／ｍＬ血，最小检出浓度为０．１～０．４μｇ／ｍＬ血。用所建的ＧＣ方法对１１例中毒病人的生物样品进行分析鉴定，ＧＣ－ＭＳ法验证。从实际中证明所建方法操作简便，准确性和系统性强，灵敏度较高，能快速、准确地为医院的救治提供依据。     

聚氨酯醇酸的裂解气相色谱-质谱研究

人工合成聚氨酯醇酸,用裂解气相色谱－质谱（ＰＧＣ－ＭＳ）法详细研究其热裂解产物的化学组成,探索其热裂解机理。裂解的主要产物为合成所用的单体甲苯二异氰酸酯（ＴＤＩ）、邻苯二甲酸酐及油脂相应的脂肪酸。     

单叶蔓荆子挥发油成分的GC/MS分析

采用气相色谱／质谱（ＧＣ／ＭＳ）联用技术对山东泰山产单叶蔓荆子挥发油的化学成分进行了分析,分离出３０多个峰,确认了其中２８种成分,占总离子流的９５％以上,并对挥发油的主要化学成分Δ３－蒈烯,用气相色谱／傅里叶红外光谱（ＧＣ／ＦＴＩＲ）法进行了验证。     

气相色谱－原子发射光谱联用仪测定18种安眠镇静药的元素比例及其在中毒病人全血样品中的应用

采用气相色谱－原子发射光谱联用仪（ＧＣ－ＡＥＤ）测定了１８种安眠镇静药的元素组成和元素比例。根据气相色浴－质谱（ＧＣ－ＭＳ）测定的分子量数据推测出它们的分子式，结果与实际值一致。以元素组成、元素比例和保留时间为判据，对一例中毒患者全血样品进行了定性分析，发现血中含有苯巴比妥。     

芳香烃异构体的毛细管柱气相色谱—傅里叶变换红外光谱联用技术分析

采用国产色谱仪与进口红外光谱仪及接口组成的气相色谱－傅里叶变换红外光谱（ＧＣ／ＦＴＩＲ）分析仪，使用大口径毛细管柱，分析了乙苯与苯乙烯固相催化反应液的复杂芳香烃异构体组成，讨论了ＧＣ／ＦＴＩＲ分析中随机噪声和基线漂的去除方法。采用等高线图９ＣＴＤ）分析技术得混合液中各组分的纯气相红外光谱图，最后了１４个气相色谱峰中的９个，占整个色谱峰面积９９５以上。     

气相色谱—红外光谱联用技术及其在催化反应机理研究中的应用

气相色谱－红外光谱（ＧＣ－ＩＲ）联用技术，在催化反应产物分析及催化机理的研究中具有独到的优越性。利用气相色谱－红外光谱联用仪，对多相催化反应产物及均相催化反应产物进行分析，捕捉到了一些对催化反应机理研究产生影响的物种。     

气相色谱－原子发射光谱联用仪测定18种安眠镇静药的元素比例及其在中毒病人全血样品中的应用

 采用气相色谱－原子发射光谱联用仪（ＧＣ－ＡＥＤ）测定了１８种安眠镇静药的元素组成和元素比例。根据气相色浴－质谱（ＧＣ－ＭＳ）测定的分子量数据推测出它们的分子式，结果与实际值一致。以元素组成、元素比例和保留时间为判据，对一例中毒患者全血样品进行了定性分析，发现血中含有苯巴比妥。     

气相色谱－质谱法测定赤鳞鱼肉中的脂肪酸

利用气相色谱质谱（ＧＣ／ＭＳ）电子轰击方法，对６种不同年龄和不同性别的赤鳞鱼肉中的饱和、不饱和脂肪酸（经甲酯化后）进行了测定，用色谱法作了定量，共鉴定出１８种脂肪酸。     

Purification and in vitro Activity of an Antimicrobial Peptide from Skin of Rana Temporaria Chensinensis, David

In this study,an antimicrobial component(RTCI)was purified from the skin of Rana temporaria chensinensis,David.Antimicrobial activities of RTCI against clinical multi-drug resistant bacterial strains,including Escherichia coli,Pseudomonas aeruginosa,Staphylococcus aureaus,Klebsiella oxytoca,Klebsiella pneumoniae,Enterococcus faecalis,and Proteus mirabilis were measured in vitro by means of minimal inhibitory concentration and time-kill studies.The results indicate that RTCI could inhibit the growth of these bacteria at a proper concentration and suggest that RTCI shows a better antimicrobial activity to Gram-negative bacterial strains than to Gram-positive bacterial strains.     

Purification and Characterization of an Antibacterial Peptide from Rana Temporaria Chensinensis Skin

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一种中国林蛙抗菌肽的光谱研究

从中国林蛙皮中纯化得到了一种抗多种临床多重耐药菌的抗菌肽(RTCⅠ), 初步氨基酸组成分析结果表明其不含碱性氨基酸, 此抗菌肽在276.5和356.5 nm波长光的激发下发射出448 nm的荧光, 利用傅里叶变换红外光谱、拉曼光谱、电子吸收光谱及荧光光谱等技术研究了此特定荧光产生的结构依据. 此抗菌肽的主要组成是Tyr, Asn(Asp)和Glu(Gln), 抗菌肽特殊的荧光光谱和电子吸收谱与Tyr的酚羟基和Asn侧链的强氢键有关. 这一特殊的荧光(448 nm)及圆二色谱(259, 263和267 nm)信号为进一步在分子水平上研究此抗菌肽的抗菌机理提供了依据.     

Evaluation of gas chromatographic methods for the determination of <Emphasis Type="Italic">trans</Emphasis> fat

Consumption of trans fat has been associated with increased risk of coronary heart disease. For nutrition labeling purposes, the US Food and Drug Administration (FDA) defines trans fat as the sum of all the fatty acids with at least one nonconjugated double bond in the trans configuration. The FDA regulation states that label declarations of trans fat are not required for products that contain less than 0.5 g of trans fat per serving if no claims are made about fat, fatty acids or cholesterol. While attenuated total reflection Fourier-transformed infrared spectroscopy (ATR-FT-IR) provides reproducible measurements for samples containing more than 5% trans fat, methods based on gas chromatography (GC) are needed to measure lower trans fat levels. Trans fat quantitation by GC has recently been updated by considering more fatty acids, focusing more attention on fatty acids present in low amounts, and by using 100-m high-polarity capillary columns for optimal separation. The consistently high interlaboratory relative standard deviations (RSD, e.g., 21% at 1% trans fatty acids (TFA), 60% at 0.17% TFA), and intralaboratory RSD values (e.g., 10% at 1% TFA, 16% at 0.17% TFA) for trans fat at 1% or less of total fat reported in the collaborative study data for American Oil Chemists Society Official Method Ce 1h-05 suggest the need to carefully define the parameters associated with GC analysis of fatty acids.     

Determination of lipids in infant formula powder by direct extraction methylation of lipids and fatty acid methyl esters (FAME) analysis by gas chromatography.

Fatty acid methyl esters (FAMEs) of pure triglyceride standards, oils, and fat from dry matrixes were formed by transesterification using sodium methoxide in methanol-hexane. FAMEs were produced by direct addition of sodium methoxide-hexane to samples and heating to simultaneously extract and transesterify acyl lipids. FAMEs were quantitated by capillary gas chromatography (GC) over a fatty acid concentration range of 0 to 1.7 mg/mL (r > or = 0.9997). Total fat was calculated as the sum of individual fatty acids expressed as triglyceride equivalents, in accordance with nutrition labeling guidelines. Saturated, polyunsaturated, and monounsaturated fats were calculated as sums of individual free fatty acids. Absolute recoveries determined from individual fatty acids in test samples ranged from 69.7 to 106%. Recoveries (relative to the C13:0 internal standard) for individual fatty acids in test samples ranged from 95 to 106%. Reproducibility was constant at each fatty acid level in the reaction mixture (n = 5, coefficient of variation [CV] < 2%). Absolute recovery determined from the sum of total fatty acids in standard reference material (SRM) 1846 (powdered infant formula) was 96.4%. Analysis of SRM 1846 gave results that agreed closely with the certified fat and fatty acid values. Analysis of commercial infant formula gave results that were comparable to those obtained with AOAC Method 996.01. The direct extraction methylation procedure is rapid, and the transesterification of acyl lipids to form FAMEs is complete within 15 min. Classical saponification and refluxing are not required. This method provides FAMEs free of interferences and easily quantitated by GC or confirmed by GC/mass spectrometry (MS). Unambiguous MS identification of individual FAMEs derived from pure standards, SRM 1846, and powdered infant formula product was obtained.     

Quantitative determination of prostaglandins E1, E2 and E3 in frog tissue

A method was developed for quantitative determination of endogenous production of prostaglandin (PG)E1, PGE2 and PGE3 by Rana temporaria lung, heart and urinary bladder homogenates, since these tissues contain the precursors, 8,11,14-eicosatrienoic, arachidonic and 5,8,11,14,17-eicosapentaenoic acids. Following homogenization and shaking at 22 degrees C for 30 min, media were extracted by XAD-2, treated with sodium hydroxide in order to convert PGE compounds into PGB compounds, purified by thin-layer chromatography, and analyzed by high-performance liquid chromatography with homo-PGE1 as an internal standard. The ratio of prostaglandins E1, E2 and E3 compared to the ratio of fatty acid precursors in tissue suggested that the tissue content of precursor is not the only factor determining the type of prostaglandin synthesized.     

In-house validation of an improved sample extraction and clean-up method for GC determination of isomers of nervonic acid in meat products

An improved extraction and clean-up method for determination of brain-specific fatty acids, in particular lignoceric acid (C24:0) and the cis/ trans isomers of nervonic acid (15 c-t C24:1), in meat products has been developed. The method is based on isolation of the polar lipids of interest from the bulk lipids by solid-phase extraction. The fatty acids, derivatised to their fatty acid methyl esters, are quantified by GC in a DB5 column. Fresh meat samples were extracted by using a mixture of n-butanol:hexane (1:9) as solvent. The extract was loaded in a silica gel cartridge column previously equilibrated with hexane. The first fraction containing the major part of the fat was eluted with hexane while acetone and methanol allowed the elution of fatty acids bound to polar moieties such as nervonic and lignoceric acids. This second fraction containing the analyte was methylated and injected into the GC for quantification after addition octacosane (C(28)) as internal standard.     

人体胎盘合体滋养细胞质膜的脂肪酸组成分析

用Ｗｈｉｔｓｅｔｔ法提取１８只正常足月妊娠分娩的胎盘合体滋养细胞质膜（ＳＰＭ）,采用Ｌａｎｄｏｎ法提取脂质,使用气相色谱法和丁二酸二乙二醇酯（ＤＥＧＳ）填充柱分离测定ＳＰＭ的脂肪酸,结合气相色谱／质谱定性,将１３种碳数大于１４的脂肪酸进行了定性和定量。定量出的脂肪酸占出峰物质总量的７４．１％,其中饱和脂肪酸为３０．６４％,不饱和脂肪酸为４３．４６％。     

银离子固相萃取-气相色谱法检测乳脂肪中的反式脂肪酸

建立了分离反式油酸(C18:1)、亚油酸(C18:2)、亚麻酸(C18:3)的银离子固相萃取-气相色谱(Ag+-SPE/GC)方法,并应用于乳脂肪中反式脂肪酸的检测。采用自制的银离子固相萃取柱对样品进行预分离,总脂肪酸甲酯化后上样,依次经9 mL甲苯-正己烷(体积比5:95)、8 mL甲苯-正己烷(体积比17:83)、6 mL甲苯-乙酸乙酯(体积比17:83)、10 mL甲苯-乙酸乙酯(体积比30:70)洗脱并分别收集洗脱液,采用气相色谱分别进行检测。结果显示,除了反式亚麻酸的回收率为69.9%～101.0%、相对标准偏差(RSD)为11.0%～18.1%外,其余的反式脂肪酸的回收率均为88.4%～107.2%、RSD为1.2%～11.9%。该方法通过特异性固相萃取的方法对样品进行前处理,较好地避免了样品中顺式及饱和脂肪酸对反式脂肪酸检测的干扰。     

MAP: microwave-assisted extraction of fatty acids and Py/GC/MS analysis of selected insects

A Microwave-Assisted Process (MAP) solvent extraction procedure was used in conjunction with GC/MS analysis to investigate the chemical composition of dried silkworm, dried earthworm, silkworm droppings, and cicada nymph skin. Selected insect samples were also analyzed by pyrolysis-GC-MS. Silkworm and earthworm generated fatty acids, sterols and phenol derivatives. Cicada nymph skin was analyzed by pyrolysis/GC/MS and generated mainly heterocyclic compounds. The data indicated that insects can retain environmental contaminants such as 2,6-bis(1,1-dimethylethyl)-4-methyl phenol (BHT) and as such could be used as biological indicators. In addition, some of the therapeutic characteristics associated with insects could be attributed to the chemicals ingested from plant sources.