Abstract
There are several methods for quantifying malondialdehyde (MDA), an oxidative stress biomarker, in exhaled breath condensate (EBC). However, due to the very diluted nature of this biological matrix, a high variability is observed at low concentrations. We aimed to optimize a 2,4-dinitrophenylhydrazine-based method using liquid chromatography coupled to tandem mass spectrometry and characterize the uncertainty associated with this method. We investigated the following parameters for the method validation: calibration linearity, limit of detection (LOD), precision, recovery, and matrix effect. The results were used to identify the main sources of uncertainty and calculating the combined uncertainty. The applicability of this method was evaluated in an ongoing epidemiological study by analyzing 164 EBC samples collected from different professional groups in subway environments. The optimized method was sensitive (LOD: 70 pg/mL), precise (inter-day variation < 19%) and accurate (recovery range: 92–106.5%). The calculated analytical uncertainty was the highest at the LOQ level and reached 23%. Although the analytical uncertainty was high at low MDA concentrations, it was significantly lower than that the observed inter-individual variability. Hence, this method performs sufficiently well and can be recommended for future use in epidemiological researches relying on between-subject differences.
Highlights
The burden of non-communicable chronic disease is increasing in the most developed, but is increasing in developing countries [1]
The 6 min washing period with eluent A at the end of the gradient program avoided a carry-over between different samples and protecting the analytical LC-mass spectrometer (MS) system from solid deposition [38]
We developed an optimized LC–electrospray ionization (ESI)-MS/MS method for MDA detection and quantification in exhaled breath condensate (EBC) using DNPH as the derivatizing agent
Summary
The burden of non-communicable chronic disease is increasing in the most developed, but is increasing in developing countries [1]. Most of these diseases, including cardiovascular diseases, respiratory diseases, and cancer include oxidative stress and inflammation mechanism in the disease pathway. The presence of ROS is quantified indirectly by measuring oxidized products, known as oxidative stress biomarkers. Oxidized lipids and their metabolites have been proposed as biomarkers of oxidative stress [3], as lipids are concentrated in biological membranes and are vulnerable to ROS [4,5]. A great variety of lipid hydroperoxides is formed depending on the degree and mechanism of oxidation [6,7]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
