Precipitation of soluble affinity complexes by a second affinity interaction: a model study

Lactate dehydrogenase was purified by affinity precipitation. The enzyme bound to Blue Dextran (the Cibacron blue residues) and was precipitated by addition of concanavalin A. The lectin functions as a crosslinking agent, building up large flocs of dextran that subsequently precipitate, thus co-precipitating the affinity-bound lactate dehydrogenase.