摘要:本文用反相C18柱和巯基键合银离子柱分析三种食用油,结合APCI正离子质谱检测,对所得到各组分峰进行定性鉴别。得到质谱图中包括甘油二酯碎片([M+H—RCOOH]+峰)和分子离子峰([M+H]+)。因此本论文根据待测食用油脂肪酸的类型和含量,通过观察甘油三酯的分子离子峰(M+H)+以及甘油二酯碎片离子峰(M+H-RCOOH)+ 的峰簇,并考虑C18柱以碳当量分离、银离子柱以双键数分离的特点,来对各个峰进行定性识别。使用银离子巯基键合柱分析结果为,橄榄油主要由OOO组成,其他含量较大的甘油三酯分别为PPO、OPO和OLO。葵花籽油主要由LLL组成,其他含量较大的甘油三酯分别为OPO、OOO和PLL。大豆油的甘油三酯主要包括LLL、LLO、OOL和POL。这三种食用油中均未发现全饱和的甘油三酯。使用反相键合C18柱分析了葵花籽油和大豆油,定性的结果与银离子柱的结果基本一致。还将C18柱分离葵花籽油三个峰的馏分分别用气相色谱质谱联用检测,气质检测三个馏分的结果均能在液质结果中找到对应。24126
毕业论文关键词:高效液相色谱法;食用油;甘油三酯;定性
Qualitative analysis of edible oil using High performance liquid chromatography
Abstract:This paper describes an HPLC/MS procedure for the determination of main componments in three vegetable oils. The chromatographic separation was achieved using two different columns, reversed phase C18 column and sulfhydryl bond silver ion column. The detection was performed by atmospheric pressure chemical ionization (APCI) positive ion mass spectra. The mass spectrum consists of diacylglycerol fragments, namely [M+H-RCOOH]+, and the molecular ion peak, namely [M+H]+. According to the type and content of fatty acids in those three edible oils, the TAGs were identified on the basis of the peaks observed from their positive APCI mass spectra using [M+H]+ ions for the molecular weight determination and [M+ H -RCOOH] fragment ions for the identification of inpidual fatty acids. The facts that TAGs are separated by equivalent carbon number (ECN) using C18 column and that silver ion column separation is based on the number of double bonds (DB) were also taken into consideration when recognizing the TAG groups. Silver ion sulfhydryl bond column analysis found that olive oil is mainly composed of OOO, followed by PPO, OPO and OLO; sunflower seed oil is mainly composed of LLL, also contains OPO, OOO and PLL; the main triglycerides (TAGs) of soybean oil were represented by LLL, LLO, OOL and POL. Saturated triglycerides were not found in these three kinds of edible oil. Using reversed-phase bonded C18 column to analyze soybean oil got the the same results with silver ion column analysis. Combining gas chromatography mass spectrometry to detect the fractions of sunflower seed oil separated by C18 column, we found that the GC-MS results of the three major fractions are all confirmed by the corresponding results of LC-MS.
KeyWords: High performance liquid chromatography; edible oil; triglyceride; qualitative
目录
1 前言 1
1.1 选题意义 1
1.2.1食用油中甘油三酯的分析 3
1.2.2食用油中其他少量物质的分析 4
2 仪器与试剂 12
2.1仪器 12
2.2 试剂与样品 12
2.2.1 试剂 12
2.2.2样品 12
2.3色谱柱 13
3 实验内容 14
3.1 液质联用法分析食用油 14
3.1.1银离子巯基键合柱分析橄榄油,大豆油和葵花籽油 14
3.1.2反相C18柱分析大豆油和葵花籽油 14
3.2 液相色谱离线串联气质联用法分析葵花籽油 14
3.2.1 选择合适的溶剂 15 高效液相色谱分离食用油各组分的定性研究:http://www.751com.cn/huaxue/lunwen_17483.html