Aggregation of amphiphilic pullulan derivatives evidenced by on-line flow field flow fractionation/multi-angle laser light scattering.

Size-exclusion chromatography (SEC) is a useful steric separation technique for the analysis of water-soluble polysaccharides in aqueous solution. However, in the case of amphiphilic derivatives, the usefulness is limited because of interactions between hydrophobic segments and the stationary phase. Alkyl-bearing pullulans differing from the extent and the length of alkyl groups were characterized using flow-field flow fractionation with on-line coupling multi-angle laser light scattering (F4/MALLS). Comparison of SEC and F4 is presented and the interest of F4 in the field of amphiphilic derivatives is demonstrated.