title: Lactose does not interfere with the analysis of sialic acids as their 1,2-diamino-4,5-methylenedioxybenzene derivatives.
abstract: In 2007, Martin et al. developed a method for the analysis of sialic acids by HPLC following 1,2-diamino-4,5-methylenedioxybenzene (DMB) derivatisation (Martín et al., Anal Bioanal Chem 387:2943-2949, 2007). Within the article, the authors noted that lactose interfered with the analysis, giving erroneously high results when lactose-containing products were analysed. Such an observation is important when analysing milk-based products, yet was contradictory to the observations of Nakamura et al. (Chem Pharm Bull 35(2):687-692, 1987) who demonstrated that DMB was specific for α-keto acids and did not react with simple sugars such as glucose or lactose. In order to clarify the situation, this phenomenon was investigated and it was confirmed that lactose does not interfere with the analysis. However, it was found that most commercial preparations of lactose do contain small amounts of sialic acids, either as the free monosaccharide or bound to lactose in the form of 3'- and 6'-sialyllactose.
authors.affiliation: Quality and Safety Department, Nestlé Research Centre, Vers-Chez-Les-Blanc, 1000 Lausanne, Switzerland.
authors.forename: Véronique
authors.initials: V
authors.lastname: Spichtig
authors.forename: Philippe
authors.initials: P
authors.lastname: Rohfritsch
authors.forename: Sean
authors.initials: S
authors.lastname: Austin
mesh_terms: D002851:Chromatography, High Pressure Liquid; D006868:Hydrolysis; D007785:Lactose / Q000737:chemistry*; D010655:Phenylenediamines / Q000737:chemistry*; D012794:Sialic Acids / Q000032:analysis*
chemical_list: D010655:Phenylenediamines; D012794:Sialic Acids; C058886:1,2-diamino-4,5-methylenedioxybenzene; D007785:Lactose