Allium sativum lectin (ASA) is purified first with affinity chromatography and then with gel filtration. It is a dimer of two subunits. ASA binds to a number of Î±1-2-linked mannose residues. The lectin recognizes internal mannose and binds to the core pentasaccharide of N-linked glycans. In addition, the removal of sialic acids enhances binding activity. Allium sativum Lectin (ASA) is conjugated to ferritin, that has a molecular weight of 474,000 g/mol (all 24 subunits combined). Ferritin-conjugated lectins can be used to visualize localization of specific saccharide moieties and examine the distribution of plasma membrane glycoproteins. These conjugates can be viewed via electron microscopy.