A Caveat When Using Alkyl Halides as Tagging Agents to Detect/Quantify Reactive Sulfur Species

Using alkyl halides to tag reactive sulfur species (RSSs) (H2S, per/polysulfide, and protein-SSH) is an extensively applied approach. The underlying supposition is that, as with thiols, RSS reacts with alkyl halides via a nucleophilic substitution reaction. We found that this supposition is facing a challenge. RSS also initiates a reductive dehalogenation reaction, which generates the reduced unloaded tag and oxidized RSS. Therefore, RSS content in bio-samples might be underestimated, and its species might not be precisely determined when using alkyl halide agents for its analysis. To calculate to the extent of this underestimation, further studies are still required.

Automated summary

The use of alkyl halides to tag reactive sulfur species faces a challenge as RSS can also initiate a reductive dehalogenation reaction, generating reduced tag and oxidized RSS. This may lead to underestimation of RSS content in bio-samples and inaccuracies in determining its species when using alkyl halide agents for analysis. Further studies are needed to quantify the extent of this underestimation.