New enzymatic determination of sialic acid in serum.

This enzymatic method for determination of sialic acid involves use of neuraminidase (EC 3.2.1.18), N-acetylneuraminate lyase (EC 4.1.3.3), acylglucosamine 2-epimerase (EC 5.1.3.8), N-acetylhexosamine oxidase (from Pseudomonas sp.), and peroxidase (EC 1.11.1.7). Because the method does not require pyruvic acid in the assay medium, interference by pyruvic acid in serum can be avoided. This simple, accurate assay is little affected by other substances in serum.