A simple, optimized method for the determination of sulphide in whole blood by GC–MS as a marker of bowel fermentation processes

Hydrogen sulphide is produced in human large intestine by anaerobic fermentation and may play a pathogenic role. An analytical method for determination of sulphide in whole blood using an extractive alkylation technique was optimised and validated for this purpose. The sample was mixed with organic phase containing pentafluorobenzyl bromide as an alkylating agent. The benzalkonium chloride was used as a phase-transfer catalyst. The quantitative determination was performed using GC–MS technique in selected ion monitoring mode. The blood levels of sulphide of healthy controls were measured (35–80 μM/l). The method is versatile, reproducible (RSD=2.7%) and suitable for research of anaerobic fermentation in vivo.