Issue 1, 2023

Overcoming the lack of authentic standards for the quantification of biogenic secondary organic aerosol markers

Abstract

Liquid chromatography coupled to electrospray ionisation high resolution mass spectrometry is an extremely powerful technique for both targeted and non-targeted analysis of organic aerosol. However, quantification of biogenic secondary organic aerosol species (BSOA) is hindered by a lack of commercially available authentic standards. To overcome the lack of authentic standards, this study proposes a quantification method based on the prediction of relative ionisation efficiency (RIE) factors to correct concentrations obtained via calibration using a proxy standard. RIE measurements of 89 commercially available standards were made relative to cis-pinonic acid and coupled to structural descriptors. A regularised random forest predictive model was developed using the authentic standards (R2 = 0.66, RMSE = 0.59). The model was then used to predict the RIE’s of 87 biogenic organic acid markers from α-pinene, limonene and β-caryophyllene without available authentic standards. The predicted RIE’s ranged from 0.27 to 13.5, with a mean ± standard deviation of 4.2 ± 3.9. 25 markers were structurally identified in chamber samples and ambient aerosol filter samples collected in summertime Beijing. The markers were quantified using a cis-pinonic acid calibration and then corrected using the predicted RIE factors. This resulted in the average BSOA concentration decreasing from 146 ng m−3 to 51 ng m−3, respectively. This change in concentration is highlighted to have an impact on the types of average aerosol metrics commonly used to describe bulk composition. This study is the first of its kind to use predicted ionisation efficiency factors to overcome known differences in BSOA concentrations due to the inherent lack of authentic standards in aerosol chemistry.

Graphical abstract: Overcoming the lack of authentic standards for the quantification of biogenic secondary organic aerosol markers

Supplementary files

Transparent peer review

To support increased transparency, we offer authors the option to publish the peer review history alongside their article.

View this article’s peer review history

Article information

Article type
Paper
Submitted
22 Jun 2022
Accepted
27 Nov 2022
First published
14 Dec 2022
This article is Open Access
Creative Commons BY license

Environ. Sci.: Atmos., 2023,3, 221-229

Overcoming the lack of authentic standards for the quantification of biogenic secondary organic aerosol markers

D. J. Bryant, A. W. Mayhew, K. L. Pereira, S. H. Budisulistiorini, C. Prior, W. Unsworth, D. O. Topping, A. R. Rickard and J. F. Hamilton, Environ. Sci.: Atmos., 2023, 3, 221 DOI: 10.1039/D2EA00074A

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements