Capillary zone electrophoresis to study the hydrolytic degradation of a novel gluconic/glycolic/lactic acid copolymer

A typical member of the novel family of hydrolytically degradable aliphatic polyesters resulting from the copolymerisation of (3-(1,2-3,4-tetraoxobutyl-diisopropylidene)-dioxane-2,5-dione) (DIPAGYL) and racemic lactide under powder form was allowed to degrade in phosphate buffer saline at 55 degrees C. Capillary zone electrophoresis was used to monitor the water-soluble derivatives present in the ageing medium. Indirect UV detection using p-anisate as the absorbing anion was described and the conditions to achieve quantitative determination were defined. The method was applied to monitor the fate of a couple of dimeric intermediates, namely lactyllactate and gluconylglycolate and glycolylgluconate. The method can also be used to evaluate the total amount of released compounds, despite the fact that higher water-soluble oligomers could not be detected because of a too short lifetime. Last but not least, it was proved that the copolymer did return to its ultimate building blocks, namely gluconic, glycolic and lactic acids. (C) 2000 Elsevier Science Ltd. All rights reserved.