Flow injection analysis of polymeric excipients used in pharmaceutical formulations

Both hydrophobic and hydrophilic polymer matrices are used in pharmaceutical controlled-release formulations. In order to fully understand the functionality of the polymer in the drug delivery device, it is useful to study both the properties of the material before formulation and the behavior of the polymer in situ. A flow injection size exclusion chromatography approach is described that permits the rapid determination of polymer properties. Examples are given for the application of this method to real-time monitoring of the polymerization of poly(lactide-co-glycolide) and to the study of polymer release from swellable matrix tablets.