Determination of hydrogen sulfide in a yeast culture solution by flow analysis utilising methylene blue spectrophotometric detection

Gas diffusion and flow injection analysis with a spectrophotometric detecto r has been developed for the determination of sulfide in a yeast culture so lution. A detection limit (signal-to-noise ratio = 3) of 0.2 mu M sulfide w as achieved. A relative standard deviation of 3.4% (n = 12) was also achiev ed for 0.5 mu M sulfide. The technique is highly sensitive, accurate and pr ecise, with low susceptibility to interferences, and allows significant rea gent and instrument economy.