Holcapek Michal, Jandera Pavel, Zderadicka Petr, Hrubá Lucie
Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Nám Cs Legií 565, 53210 Pardubice, Czech Republic.
J Chromatogr A. 2003 Aug 29;1010(2):195-215. doi: 10.1016/s0021-9673(03)01030-6.
Triacylglycerols (TGs) and diacylglycerols (DGs) in 16 plant oil samples (hazelnut, pistachio, poppy-seed, almond, palm, Brazil-nut, rapeseed, macadamia, soyabean, sunflower, linseed, Dracocephalum moldavica, evening primrose, corn, amaranth, Silybum arianum) were analyzed by HPLC-MS with atmospheric pressure chemical ionization (APCI) and UV detection at 205 nm on two Nova-Pak C18 chromatographic columns connected in series. A single chromatographic column and non-aqueous ethanol-acetonitrile gradient system was used as a compromise between the analysis time and the resolution for the characterization of TG composition of five plant oils. APCI mass spectra were applied for the identification of all TGs and other acylglycerols. The isobaric positional isomers can be distinguished on the basis of different relative abundances of the fragment ions formed by preferred losses of the fatty acid from sn-1(3) positions compared to the sn-2 position. Excellent chromatographic resolution and broad retention window together with APCI mass spectra enabled positive identification of TGs containing fatty acids with odd numbers of carbon atoms such as margaric (C17:0) and heptadecanoic (C17:1) acids. The general fragmentation patterns of TGs in both APCI and electrospray ionization mass spectra were proposed on the basis of MSn spectra measured with an ion trap analyzer. The relative concentrations of particular TGs in the analyzed plant oils were estimated on the basis of relative peak areas measured with UV detection at 205 nm.
采用高效液相色谱-质谱联用仪（HPLC-MS），配备大气压化学电离源（APCI），并在205 nm波长下进行紫外检测，在两根串联的Nova-Pak C18色谱柱上对16种植物油样品（榛子、开心果、罂粟籽、杏仁、棕榈、巴西坚果、油菜籽、澳洲坚果、大豆、向日葵、亚麻籽、香青兰、月见草、玉米、苋菜、水飞蓟）中的三酰甘油（TGs）和二酰甘油（DGs）进行了分析。使用单一色谱柱和非水乙醇-乙腈梯度系统，以在分析时间和五种植物油TG组成表征分辨率之间达成折衷。APCI质谱用于鉴定所有TGs和其他酰基甘油。基于与sn-2位相比，sn-1(3)位脂肪酸优先损失形成的碎片离子的不同相对丰度，可区分等压位置异构体。出色的色谱分辨率和较宽的保留窗口，再加上APCI质谱，能够对含有奇数碳原子脂肪酸（如十七烷酸（C17:0）和十七碳烯酸（C17:1））的TGs进行阳性鉴定。基于用离子阱分析仪测得的MSn光谱，提出了APCI和电喷雾电离质谱中TGs的一般裂解模式。根据在205 nm波长下紫外检测测得的相对峰面积，估算了分析的植物油中特定TGs的相对浓度。
