Byrdwell W C, Emken E A, Neff W E, Adlof R O
FQS, NCAUR, ARS, USDA, Peoria, Illinois 61604, USA.
Lipids. 1996 Sep;31(9):919-35. doi: 10.1007/BF02522685.
Atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) was used for quantitative analysis of triglycerides (TG) separated by reverse-phase high-performance liquid chromatography. APCI-MS was used for analysis of mono-acid TG standards containing deuterated internal standard, of a synthetic mixture of heterogeneous TG, of randomized and normal soybean oils and of randomized and normal lard samples. Quantitation of the TG by four approaches based on APCI-MS were compared, and these were compared to quantitation obtained using liquid chromatography (LC) with flame-ionization detection (FID). The APCI-MS methods were based on (i) calibration curves from data for mono-acid TG standards, (ii) response factors obtained from a synthetic mixture of TG, (iii) response factors calculated from comparison of randomized samples to their statistically expected compositions, and (iv) response factors calculated from comparison of fatty acid (FA) compositions calculated from TG compositions to FA compositions obtained by calibrated gas chromatography (GC) with FID. Response factors derived from a synthetic mixture were not widely applicable to samples of disparate composition. The TG compositions obtained using APCI-MS data without application of response factors had average relative errors very similar to those obtained using LC-FID. Numerous TG species were identified using LC/APCI-MS which were undetected using LC-FID. Two quantitation methods, based on response factors calculated from randomized samples or on response factors calculated from FA compositions, both gave similar results for all samples. The TG compositions obtained using response factors calculated from FA compositions showed less average relative error than was obtained from LC-FID data, and were in good agreement with predicted compositions for the synthetic mixture and for randomized soybean oil and lard samples.
大气压化学电离质谱法（APCI-MS）用于对通过反相高效液相色谱分离的甘油三酯（TG）进行定量分析。APCI-MS用于分析含有氘代内标物的单酸TG标准品、异构TG的合成混合物、随机化和正常大豆油以及随机化和正常猪油样品。比较了基于APCI-MS的四种TG定量方法，并将其与使用带有火焰离子化检测（FID）的液相色谱（LC）获得的定量结果进行比较。APCI-MS方法基于：（i）单酸TG标准品数据的校准曲线；（ii）从TG合成混合物获得的响应因子；（iii）通过将随机化样品与其统计预期组成进行比较计算得到的响应因子；（iv）通过将由TG组成计算得到的脂肪酸（FA）组成与通过校准气相色谱（GC）和FID获得的FA组成进行比较计算得到的响应因子。从合成混合物得出的响应因子并非广泛适用于不同组成的样品。在不应用响应因子的情况下使用APCI-MS数据获得的TG组成的平均相对误差与使用LC-FID获得的平均相对误差非常相似。使用LC/APCI-MS鉴定出了许多使用LC-FID未检测到的TG种类。基于从随机化样品计算得到的响应因子或基于从FA组成计算得到的响应因子的两种定量方法，对所有样品均给出了相似的结果。使用从FA组成计算得到的响应因子获得的TG组成显示出比从LC-FID数据获得的平均相对误差更小，并且与合成混合物以及随机化大豆油和猪油样品的预测组成高度一致。
