Journal of Chromatography B ( IF 2.8 ) Pub Date : 2017-12-09 , DOI: 10.1016/j.jchromb.2017.12.014 Andrew Quigley , Damian Connolly , Wayne Cummins
Dispersive liquid–liquid microextraction (DLLME) was used prior to gas chromatography flame ionization detection (GC-FID) for the extraction of five fatty acids from milk taken from cows with different body condition scores. Optimum extraction conditions were: 300 μL of chloroform (extraction solvent), and 1 mL methanol (dispersive solvent). The procedure was optimised using Design of Experiments (DoE). The analytes were separated on a GC capillary column containing a polyethylene glycol stationary phase (15 m × 0.53 mm × 1.2 μm). Enrichment factors were in the range of 8–15 and limit of detection (LOD) was 0.04 μg/mL. Calibration graphs showed good linearity with coefficients of determination higher than 0.994% and relative standard deviations lower than 7%. This method provided a simple and rapid derivatisation and extraction method for the determination of fatty acids in bovine milk. It showed that there was a significant difference in the palmitic acid content of milk from cows that had an optimum body condition score (10.85 mg/mL) compared to cows that had a high body condition score (5.73 mg/mL).
中文翻译:
分散液-液微萃取在牛乳中脂肪酸谱分析中对身体状况评分变化的响应中的应用
在气相色谱火焰离子化检测(GC-FID)之前,先使用分散液-液微萃取(DLLME)从牛奶中提取五种不同身体状况评分的脂肪酸。最佳萃取条件为:300μL氯仿(萃取溶剂)和1 mL甲醇(分散溶剂)。使用实验设计(DoE)对程序进行了优化。在包含聚乙二醇固定相(15 m×0.53 mm×1.2μm)的GC毛细管柱上分离分析物。富集因子在8–15范围内,检出限(LOD)为0.04μg/ mL。校正图显示出良好的线性,测定系数高于0.994%,相对标准偏差低于7%。该方法为测定牛乳中的脂肪酸提供了一种简单,快速的衍生和提取方法。结果表明,与具有较高身体状况评分(5.73 mg / mL)的母牛相比,具有最佳身体状况评分(10.85 mg / mL)的母牛的牛奶中棕榈酸含量存在显着差异。