Aldoses Ketoses Aldonic Acids Uronic Acids Chromatography Retention Data Mass Spectrometry Fragment Ions

A gas chromatographic method which makes possible simultaneous analysis of common types of acidic and neutral sugars is described. Particular advantages are achieved with hydroxy acids, ketoses, and uronic acids. Acids and lactones are first converted into their sodium salts. Free or potential aldehydo and keto groups are transformed to oximes or O-methyloximes. Fully substituted acyclic ester and oxime trimethylsilyl derivatives are prepared with bis(trimethylsilyl)trifluoroacetamide and chlorotrimethylsilane. Syn and anti isomers of the oximes are formed, but a stationary phase can often be chosen on which the two peaks coincide. The silicone stationary phases OV-1, OV-17, QF-1, and XE-60 were used. Retention data are given for aldonic and deoxyaldonic acids, for aldoses and ketoses, and for uronic acids. Relationships between structure and retention are discussed. The derivatives are well suited to structure assessments by mass spectrometry.