Preparative liquid chromatography of carbohydrates mono- and di-saccharides, uronic acids, and related derivatives

Abstract

The general principles and practical aspects of preparative high-performance liquid chromatography (l.c.) of mono- and di-saccharides, sugars acids, lactones, and N-acetylated amino sugar derivatives are described. Milligram to gram quantities of these carbohydrates were isolated on semi-preparative (0.78 × 30 cm) or preparative (∼2.0 × 30 cm) columns packed with aminopropyl silica gel or cation-exchange resins in the H + or Ca 2+ form. Columns of aminopropyl silica gel provided better resolution of individual mono- and di-saccharides, but columns of cation-exchange resin had higher capacity and were more durable and economical to use. Preparative, cation-exchange columns were operated at flow rates of <5 mL/min and pressures of ∼1–2 MPa, allowing them to be used on unmodified analytical l.c. systems. Details are given for the efficient packing, use, and care of these columns, and on the effects of column selectivity, packing technique, and sample size on chromatographic resolution. Isolation of naturally occurring sugars from biological sources on a laboratory-packed column is described.