Quantitative Determination of Carbohydrates in Solution via a Reduction/Permethylation Technique

Abstract

A reduction/permethylation technique has been developed for the quantitative gas Chromatographie analysis of anhydrosugars, monosaccharides, and disaccharides. All derivatizations are carried out in the same vial, and transfers are not necessary until recovery of the permethylated derivatives. The reaction scheme is extremely simple and offers improved accuracy over standard GC carbohydrate analysis protocols. Emphasis is placed on quantitative compound recovery, and relative response factors are presented for several carbohydrates. The sodium hydroxide/methyl iodide permethylation reaction has also been shown to be a viable replacement for standard dimsyl anion procedures utilized for methylation analysis of polysaccharides. Application of the reduction/permethylation sequence to the analysis of the hydrolyzate resulting from the dilute sulfuric acid hydrolysis of cellulose demonstrates that reversion products account for a considerable amount of the glucose losses, with levoglucosan, 1, 6-anhydro-β-D-glucofuranose, isomaltose, and gentiobiose predominating.