Reference-free thio-succinimide isomerization characterization by electron-activated dissociation.

This study is a first-to-date identification of thio-succinimide hydrolysis isomers without using synthesized reference materials. This approach should be applicable to all thio-succinimide-linked molecules. Correct identification of thio-succinimide hydrolysis isomers may eventually benefit the development of ADCs in the future.