It becomes obvious that there are a lot of molecules containing sulfane sulfurs such as persulfides and polysulfides in living organism. These molecular species are involved in production, storage, and release of hydrogen sulfide, which is recognized as an important physiological mediator. Furthermore, recent studies reveal that persulfides and polysulfides may control intracellular signal transduction through s-sulfhydration of proteins, and function in vivo as anti-oxidants which have much higher reducing activity than glutathione in reduced form or cysteine.
Sodium polysulfides (Na2Sn) are sulfane sulfur donors which have simple structures, and exist as hydrogen polysulfides in an aqueous solution depending on pH. These reagents are necessary to for research and analysis of sulfane sulfurs in vivo.
Fig. 1 Chemical species containing sulfane sulfurs
Characteristics of polysulfides
Fig. 2 Structures of Sodium polysulfides (Na 2Sn) and the pKa values.
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