Separation and quantification of imidazoles in atmospheric particles using LC–Orbitrap‐MS. Issue 3 (14th November 2019)

• Record Type: Journal Article
• Authors: Teich, Monique; Schmidtpott, Mechthild; van Pinxteren, Dominik; Chen, Jianmin; Herrmann, Hartmut
• Is Part Of: Journal of separation science. Volume 43:Issue 3(2020)
• Page Start: 577
• Page End: 589
• Publication Date: 2019-11-14
• Subjects: brown carbon -- high resolution mass spectrometry -- imidazoles -- method development -- organic aerosols; Separation (Technology) -- Periodicals; Chromatographic analysis -- Periodicals; 543.089
• DOI: 10.1002/jssc.201900689
• Languages: English
• ISSNs: 1615-9306

Abstract

Abstract: A method using ultra‐high performance liquid chromatography coupled to a high resolution Orbitrap mass spectrometer was developed to identify and quantify imidazoles in aqueous extracts of aerosol particles. The aqueous particle extract was used without further enrichment or sample clean‐up. Five columns were tested for efficient separation of ten imidazoles and the Acquity HSS T3 column was chosen for further optimization. Low limits of detection (<25 nM) and good intraday and interday repeatability (<1.6 and <6%, respectively) were achieved. Investigation of matrix effects showed that external calibration is applicable when the loading of organic carbon in the sample is below 10 µg m −3 . The developed method was applied to ten real samples, and six out of the ten test imidazoles were successfully quantified, while six further imidazoles were qualitatively identified, among them 4‐imidazolecarboxaldehyde and 4‐methyl‐5‐imidazolecarboxaldehyde. Advantages of the method are the minimal sample preparation, the short run time for each sample, and the low detection limits. These allow for a fast and reliable quantification of imidazoles even in a large number of aqueous particle extract samples.