Procedures to purify membrane proteins usually require the use of detergents and often include affinity chromatography on lectin columns. Some detergents, especially denaturing detergents such as sodium dodecyl sulfate (SDS), can interfere with affinity chromatography by inactivating the bound lectin or by eluting it from the column together with the material of interest. We have developed a procedure that stabilizes lectin-column matrices by crosslinking with glutaraldehyde. This procedure does not impair the binding capacity of the immobilized lectin. It permits subsequent elution by SDS of bound glycoproteins without coelution of lectin subunits.