Stable isotope labeling method with sensitive identification and accurate quantitation function for aldehydes in fried foods

Abstract

Deuterated dansylhydrazine (d6-DH) was prepared by one step simple reaction, and applied to the stable isotope labeling (SIL) of aldehydes with the aid of commercially available dansylhydrazine (DH). Common multiple reaction monitoring (MRM) parameters was obtained by a few standard samples and then applied to other aldehydes. Hence levels of unknown aldehydes in real samples was identified using the sensitive MRM mode but not the traditional scan mode. The SIL strategy also enhanced the quantitation accuracy because samples and standards were d6-DH and DH labeled respectively, and then mass spectrum (MS) analyzed simultaneously. Analytes and standards were analyzed in identical MS conditions, and thus matrix effect which caused by different ionization efficiency between samples and standards was greatly minimized. The proposed method was applied to the SIL analysis of 21 aldehydes with limits of detection (LODs) ranged from 8.0 − 14.2 ng/kg. The recoveries were in the range of 85.3–96.4%, and the matrix effect was in the range of 90.1–102.6%.