Hydrophilic Interaction Liquid Chromatography - A Potential Alternative for the Analysis of Dextran-1

A method for the analysis of dextran-1 has been developed using hydrophilic interaction liquid chromatography (HILIC) with charged corona aerosol detection (CCAD) as a potential alternative to the size exclusion chromatography method described in the European Pharmacopoeia (EP). The EP method is in excess of 500 minutes and is considered long for routine analysis of multiple samples. The developed method retains resolution between monomers, whilst performing separation within 13 minutes.

Introduction
Dextran is a complex mixture of polysaccharides, principally of the α-1,6- glucan type, which is produced by the fermentation of sucrose by certain lactic acid bacteria, e.g. Leuconostoc mesenteroides and Streptococcus mutans. Clinical grade dextran
is produced using Leuconostoc mesenteroides strain NRRL B-512 = CIP 78.59 or substrains thereof.1 The polymeric structure of dextran is shown in Figure 1. Being a product of a fermentation process, dextran consists of different polymer lengths.
Pharmacopoeial grade dextran is split into a number of different fractions, as defined in Table 1. The larger dextran fractions have been use clinically to reduce thrombosis.² In some patients the larger dextran fraction have the potential to induce anaphylactic reactions; this risk is reduced significantly when dextran-1 is pre-administered.³