Saraf A, Park J H, Milton D K, Larsson L
Department of Infectious Diseases and Medical Microbiology, Section of Bacteriology, University of Lund, S-223 62 Lund, Sweden.
J Environ Monit. 1999 Apr;1(2):163-8. doi: 10.1039/a809019j.
Gas chromatography-mass spectrometry (GC-MS) using a quadrupole instrument and GC-tandem MS (GC-MS-MS) using an ion trap instrument were applied to determine 3-hydroxy fatty acids (3-OH FAs) with 10-18 carbon chain lengths, specific components of the endotoxin (lipopolysaccharide, LPS) of Gram-negative bacteria, in 30 house dust samples. The two methods provided similar detection sensitivity for methyl ester/trimethylsilyl derivatives of the 3-OH FAs and allowed these acids to be distinguished from co-eluting 2-OH FA derivatives. The correlation coefficients between endotoxin activity (Limulus test) and the combined amounts of 3-OH C10, 3-OH C12, and 3-OH C14 were 0.60 and 0.61 when using GC-MS and GC-MS-MS, respectively. The superior selectivity of GC-MS-MS was illustrated in analyses of sub-milligram amounts of dust, where the chromatograms achieved by GC-MS were difficult to interpret due to a high background and several closely eluting compounds. GC-MS-MS is therefore preferable to GC-MS for determining 3-OH FAs in minute (sub-milligram) amounts of dust.
使用四极杆仪器的气相色谱 - 质谱联用（GC - MS）和使用离子阱仪器的气相色谱 - 串联质谱联用（GC - MS - MS）被用于测定30份房屋灰尘样本中碳链长度为10 - 18的3 - 羟基脂肪酸（3 - OH FAs），这是革兰氏阴性菌内毒素（脂多糖，LPS）的特定成分。这两种方法对3 - OH FAs的甲酯/三甲基硅烷基衍生物具有相似的检测灵敏度，并能将这些酸与共洗脱的2 - OH FA衍生物区分开来。使用GC - MS和GC - MS - MS时，内毒素活性（鲎试剂检测）与3 - OH C10、3 - OH C12和3 - OH C14总量之间的相关系数分别为0.60和0.61。在分析亚毫克量的灰尘时，GC - MS - MS的选择性更优，因为GC - MS得到的色谱图由于背景高和几种紧密洗脱的化合物而难以解释。因此，对于测定微量（亚毫克）灰尘中的3 - OH FAs，GC - MS - MS比GC - MS更可取。
