Quantification of acetaldehyde and carbon dioxide in the headspace of malignant and non-malignant lung cells in vitro by SIFT-MS

Abstract

Previous studies using selected ion flow tube mass spectrometry, SIFT-MS, showed that CALU-1 lung cancer cell cultures emit acetaldehyde in proportion to the number of cells in the culture medium. However, studies in another laboratory led to conflicting results, so these SIFT-MS studies have been repeated and extended to include NL20 normal lung epithelial cells and 35FL121 Tel+ telomerase positive lung fibroblast cells. Thus, SIFT-MS has been used to quantify acetaldehyde and, additionally, carbon dioxide, acetone and ethanol in the headspace of the cell culture medium alone and the headspace of the appropriate medium containing 50 x 10(6) or 80 x 10(6) cells following incubation for 16 h at 37 degrees C. Three independent experiments were carried out for each cell type for both cell numbers and for each of the two culture media used. The results showed that acetone and ethanol were only released by the culture medium, specifically from the foetal calf serum contained in the medium, and not by the cells. Acetaldehyde was also released by the medium, but at relatively lower levels than the other three compounds, and was also generated by the CALU-1 and NL20 cell cultures in proportions to the number of cells in the medium. However, following incubation, the acetaldehyde levels in the headspace of the 35FL121 Tel+ cell cultures were much lower than those present in the headspace of the medium alone. Carbon dioxide was clearly generated by the CALU-1 and 35FL121 Tel+ cells indicating that they were respiring normally, but much less was produced by the NL20 cells, presumably indicating that normal metabolism was being inhibited.

Quantitative analysis of volatile metabolites released in vitro by bacteria of the genus Stenotrophomonas for identification of breath biomarkers of respiratory infection in cystic fibrosis.

“…This removal of aldehydes from culture media by bacterial and some mammalian cells has been observed in previous studies [29][30][31][32].…”

Progress in SIFT‐MS: Breath analysis and other applications

“…Further to this, the amount of CO 2 generated was correlated with the survival rate of the cells. The detailed results of this exciting work have recently been published (Sulé-Suso et al, 2009).…”

Selected ion flow tube, SIFT, studies of the reactions of H3O+, NO+ and O2+ with some biologically active isobaric compounds in preparation for SIFT-MS analyses

“…Therefore, when studying these ion/molecule reactions with a view to establishing SIFT-MS library entries, it is essential in the presence of water molecules (humid samples) to record all the products of the reactions, obviously including the primary products of the precursor ion reactions with M and also the hydrated product ions that form from them. In our laboratories at Keele and Prague, not least prompted by our collaborations with local clinicians and groups in other universities and research institutes, we have initiated studies of the VOC emissions from cell cultures [16], bacterial cultures and processed cultures such as yoghurt, fermented meat [7], alcoholic beverages [17], and compounds involved in other biochemistries both in vitro and in vivo. In these endeavours, we are constantly recognising VOCs that we need to analyse for which SIFT-MS library entries are not yet available.…”