Gambaro Andrea, Zangrando Roberta, Gabrielli Paolo, Barbante Carlo, Cescon Paolo
Department of Environmental Sciences, University of Venice, Ca' Foscari, 30123 Venice, Italy.
Anal Chem. 2008 Mar 1;80(5):1649-55. doi: 10.1021/ac701655x. Epub 2008 Feb 2.
A method for the direct determination of levoglucosan at the picogram per milliliter level in less than 1 mL of Antarctic ice has been developed. Chemical analysis is performed by high-performance liquid chromatography with triple quadrupole tandem mass spectrometric detection. Levoglucosan, a specific molecular marker for biomass burning, is identified by negative ion electrospray mass spectrometry using m/z 161/113, 161/101, 161/85, and 161/71 as monitoring ion transitions. Contamination problems were carefully taken into account by adopting ultraclean procedures during sampling and sample pretreatment phases. The limit of detection is 3 pg mL(-1) (0.3 pg absolute amount injected); the repeatability ranges between 20% and 50% at a concentration of 20 and 9 pg mL(-1), respectively. This methodology allowed the direct determination of levoglucosan in a 1 mL sample of Antarctic ice with concentration ranges between 4 and 30 pg mL(-1). To our knowledge these are the first levoglucosan concentrations reported for Antarctic ice.
已开发出一种方法，可在不到1 mL的南极冰中直接测定皮克/毫升级别的左旋葡聚糖。化学分析通过高效液相色谱与三重四极杆串联质谱检测进行。左旋葡聚糖是生物质燃烧的一种特定分子标志物，通过负离子电喷雾质谱法，以m/z 161/113、161/101、161/85和161/71作为监测离子跃迁来识别。在采样和样品预处理阶段采用超净程序，仔细考虑了污染问题。检测限为3 pg mL⁻¹（进样绝对量为0.3 pg）；在浓度分别为20和9 pg mL⁻¹时，重复性范围在20%至50%之间。该方法能够直接测定1 mL南极冰样品中浓度范围在4至30 pg mL⁻¹之间的左旋葡聚糖。据我们所知，这些是首次报道的南极冰中左旋葡聚糖浓度。
