Sambucus Nigra Lectin (SNA, EBL), Biotinylated, 2 mg, isolated from elderberry bark, binds preferentially to sialic acid attached to terminal galactose in alpha-2,6 and, to a lesser degree, alpha-2,3 linkage. Binding is also inhibited to some extent by lactose or galactose. This lectin does not appear to bind sialic acid linked to N-acetylgalactosamine. SNA has been reported to inhibit cell-free protein synthesis. Biotinylated Sambucus nigra lectin has an appropriate number of biotins bound to provide the optimum staining characteristics for this lectin. This conjugate is supplied essentially free of unconjugated biotins and is preserved with sodium azide.