Fina Biosolutions now offers CRM197 pre-labeled with bromoacetate, allowing for the easy conjugation of thiolated antigens. FinaBio’s CRM197, EcoCRM®, is labeled with ~15 bromoacetate groups. The labeled protein is provided frozen, ready to thaw and conjugate to a thiol-containing antigen.
Examples of antigens that have been conjugated to CRM-bromoacetate include cysteine-peptides, thiol-labeled oligosaccharides, polysaccharides and proteins. Depending on the nature of the antigen, gel filtration or spin filters can be used to purify the conjugate.
PBS + 5% sucrose, pH 6.8
Store at <-20°C
Note: Use within 1 hr after thawing. Note that CRM197 will denature in acidic buffers. Care should be taken to keep the conjugation pH between 6.8 and 9 for CRM-bromoacetate. We recommend familiarity with thiol-ether conjugation. See GT Hermanson, Bioconjugate Techniques.