Hydrogen sulphide in human nasal air quantified using thermal desorption and selected ion flow tube mass spectrometry.

摘要: The discovery that hydrogen sulphide (H2S) acts as a gasotransmitter when present at very low concentrations (sub-parts per billion (ppbv)) has resulted in the need to quickly quantify trace amounts of gas complex biological samples. Selected ion flow tube mass spectrometry (SIFT-MS) is capable real-time quantification H 2S but many SIFT-MS instruments lack sufficient sensitivity for this application. In study we investigate utility combining thermal desorption with quantifying H2S 0.1–1 ppbv concentration range. Human orally or nasally derived breath, and background ambient air, were collected sampling bags dried by passing through CaCl2 pre-concentrated using sorbent trap optimised capture gas. absorbed was then thermally desorbed quantified SIFT-MS. nasal breath oral from 10 healthy volunteers 0.12 ± 0.02 (mean ± SD), 0.40 0.11 3.1 2.5 respectively, cavity H2S, without preconcentration, 13.5 8.6 ppbv. correlates well not suggesting derives mainly likely pulmonary origin. successful such air rapid analytical procedure paves way straightforward analysis may assist elucidating role plays systems.