Homobifunctional reagents procedures

The use of homobifunctional reagents in two-step protocols still creates many of the problems associated with single-step procedures, because the first protein can crosslink and... 

Bz s-imidoesters like DMS may be used to couple proteins to PE-containing liposomes by crosslinking with the amines on both molecules (Figure 22.24). However, single-step crosslinking procedures using homobifunctional reagents are particularly subject to uncontrollable polymerization of protein in solution. Polymerization is possible because the procedure is done with the liposomes, protein, and crosslinker all in solution at the same time. 

The problems of indeterminate conjugation products are amplified in single-step reaction procedures using homobifunctional reagents (Chapter 4). Single-step procedures involve the addition of all reagents at the same time to the reaction mixture. This technique provides the least control over the cross-linking process and invariably leads... 

Alkaline phosphatase is coupled to immunoglobin G antibody in a one-step procedure using the homobifunctional reagent glutaral-dehyde, which reacts with amino groups in the two proteins. The procedure is simple to perform and requires minimal equipment. 

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