Rapid detection of hydrogen sulfide produced by pathogenic bacteria in focused growth media using SHS-MCC-GC-IMS

Abstract

A new rapid method for the detection of hydrogen sulfide from pathogenic bacteria is reported. The developed method, static headspace – multi-capillary column - gas chromatography - ion mobility spectrometry (SHS-MCC-GC-IMS), has been applied to detect hydrogen sulfide evolution from 61 bacteria. The developed method has been compared against a standard triple sugar iron (TSI) agar approach, and a modified single sugar iron (SSI) agar approach. Hydrogen sulfide detection by SHS-MCC-GC-IMS using an initial inoculum of 1–1.5 × 105 CFU/mL can be achieved within 6 h, after incubation at 37 °C, with a limit of detection of 1.6 ng/mL. Data for the standard agar method against the new instrumental approach, and the modified agar method against the new instrumental approach, are compared. The specificity for the new method compared against the standard method and the modified agar approach across all 61 strains was 85.2% and 88.5% respectively, and 86.7% and 91.3% across the 23 Salmonella strains tested.