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.

CRM-bromoactate

~15 Bromoacetate/CRM₁₉₇
5 mg/ml
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.