Antigenic peptides are widely used to raise antibodies and to map epitopes. ChinaPeptides helps research teams design peptide antigens with appropriate length, hydrophilicity and conjugation handles.
Carrier protein conjugation (KLH, BSA or OVA) and MAP formats are available for immunization research programs.
A useful antigen is long enough to present a B-cell epitope, soluble enough to conjugate, and different enough from the carrier that screening can distinguish peptide-reactive antibodies. A cysteine or a spacer at one terminus is decided before synthesis so that the immunogen and the screening peptide match.
Peptide antigens do not replace protein immunogens when the native fold is the epitope. We will say so when a linear peptide is a poor stand-in for a discontinuous surface.