Conjugation, of haptens

The differential reactivity of the sterically hindered and unhindered isocyanate groups of tolylene-2,4-diisocyanate facilitates the stepwise conjugation of hapten (R) and protein (P) amino groups (Fig. 3, Rn 7). jd.jj -Difluoro-m,m -dinitrobenzene (DFDNB) reacts with numerous functionalities including primary and secondary amines, imidazoles, and phenols to yield mixtures of conjugated materials (Fig. 3, Rn 8). This reaction is apparently harder to control than the diisocyanate reactions, but it is much more versatile. 

Some reagents for the conjugation of haptens to proteins (modified after Parker, 1976)... 

Conjugation of haptens through the highly reactive chlorocarbon-ates, prepared with an equimolar amount of phosgene, is an alternative which has been used for testosterone (Erlanger et al., 1957). 

Conjugation to carriers. A wide range of proven methods are available for conjugation of haptens to their carriers, most of them using common commercially available reagents. These have been summarized previously (11,14) and many examples of their use in pesticide immunoassay development exist (3.10.12.15.19.32.35.36.38). 

SO Leung, et al. Engineering a unique glycosylation site for site-specific conjugation of haptens to antibody fragments. J Immunol 154 5919, 1995. 

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