Larreta Joana, Vallejo Asier, Bilbao Urdax, Usobiaga Aresatz, Arana Gorka, Zuloaga Olatz
Kimika Analitikoa Saila, Euskal Herriko Unibertsitatea, Bilbao, Spain.
J Sep Sci. 2007 Sep;30(14):2293-304. doi: 10.1002/jssc.200700087.
Odorous organic compounds from liquid and gas samples of animal wastes were studied by headspace (HS)-solid-phase microextraction (SPME)-GC-MS. 1-Pirenyldiazomethane (PDAM) was adsorbed/absorbed on the SPME fibre in order to obtain the corresponding ester derivatives during the preconcentration step. The SPME fibre was immersed into a PDAM solution. Then, the SPME fibre was withdrawn and exposed to the HS of the liquid cow slurry. This way derivatisation of VFAs took place in the SPME fibre together with the preconcentration of the rest of the analytes of interest. The analytes were desorbed in the hot injection port (300 degrees C) of a GC-MS for 3 min. Four different fibre types and different immersion periods of the fibre in the PDAM solution were studied in order to obtain the best sensitivity with the selected fibre. Accuracy, precision and the LODs were calculated using spiked liquid and gas samples. The possibility of storing liquid samples after sampling by preconcentration on the fibre was also considered. Storage time and temperature were studied. The optimised method was applied to the determination of the analytes in liquid and gas samples from cow slurries from an intensive production farm.
采用顶空（HS）-固相微萃取（SPME）-气相色谱-质谱联用技术研究了动物粪便液体和气体样品中的挥发性有机化合物。为了在预浓缩步骤中获得相应的酯衍生物，将1-吡喃基重氮甲烷（PDAM）吸附/吸收在SPME纤维上。将SPME纤维浸入PDAM溶液中。然后，取出SPME纤维并暴露于液态牛粪浆的顶空中。通过这种方式，挥发性脂肪酸（VFAs）在SPME纤维中发生衍生化，同时其余目标分析物被预浓缩。分析物在气相色谱-质谱联用仪的热进样口（300℃）中解吸3分钟。研究了四种不同类型的纤维以及纤维在PDAM溶液中的不同浸泡时间，以便使用选定的纤维获得最佳灵敏度。使用加标液体和气体样品计算准确度、精密度和检测限。还考虑了通过在纤维上预浓缩对采样后的液体样品进行储存的可能性。研究了储存时间和温度。将优化后的方法应用于测定集约化养殖场牛粪浆液体和气体样品中的分析物。
