Schmarr Hans-Georg, Potouridis Theodoros, Ganss Sebastian, Sang Wei, Köpp Benedikt, Bokuz Ursula, Fischer Ulrich
Dienstleistungszentrum Ländlicher Raum Rheinpfalz, Breitenweg 71, D-67435 Neustadt an der Weinstrasse, Germany.
Anal Chim Acta. 2008 Jun 9;617(1-2):119-31. doi: 10.1016/j.aca.2008.02.002. Epub 2008 Feb 9.
An improved method for the analysis of carbonyls is described utilizing a headspace solid-phase microextraction (HS-SPME) step and on-fiber derivatization with O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) hydrochloride. Thermal desorption of the oxime derivatives formed on the fiber is followed by gas chromatographic separation coupled to an ion trap tandem mass spectrometer (GC-ITMS). Selecting specific fragment ions within the electron ionization (EI(+)) mass spectra of these oxime derivatives as precursor ions for MS-MS fragmentation provides a suitable method for the target analysis of individual carbonyl classes, such as alkanals, (E)-2-alkenals, (E,E)-2,4-alkadienals, and others. Retention indices on polar as well as on apolar stationary phases along with EI(+) mass spectra patterns are presented for a large set of oxime derivatives, giving valuable information needed for unambiguous assignment of substances in complex sample matrices. The fast sample preparation and derivatization step via HS-SPME can be automated and is applicable to a variety of biological samples and foodstuffs, allowing rapid and sensitive screening analyses of important aldehydic biomarkers and aroma active compounds.
本文描述了一种改进的羰基分析方法，该方法采用顶空固相微萃取（HS-SPME）步骤，并使用盐酸O-（2,3,4,5,6-五氟苄基）羟胺（PFBHA）进行纤维上衍生化。纤维上形成的肟衍生物经热解吸后，通过气相色谱分离与离子阱串联质谱仪（GC-ITMS）联用。选择这些肟衍生物的电子电离（EI(+)）质谱中的特定碎片离子作为MS-MS裂解的前体离子，为个别羰基类别（如链烷醛、（E）-2-烯醛、（E,E）-2,4-二烯醛等）的目标分析提供了一种合适的方法。给出了一大组肟衍生物在极性和非极性固定相上的保留指数以及EI(+)质谱图，为复杂样品基质中物质的明确鉴定提供了所需的有价值信息。通过HS-SPME进行的快速样品制备和衍生化步骤可以自动化，适用于各种生物样品和食品，可对重要的醛类生物标志物和香气活性化合物进行快速灵敏的筛选分析。
