VISUALIZATION OF THE INGRESS OF WATER AND DISPERSION OF DRUGS IN A MODIFIED HYDROSILANISED SILICONE POLYMER USING COMBINED ION-BEAM ANALYSIS TECHNIQUES

A combination of the ion beam analysis techniques Nuclear Reaction Ana lysis (NRA) and Particle Induced X-ray Emission (PIXE) were used to im age the ingress of heavy water into a modified hydrosilanised silicone polymer doped with the drug chlorhexidine diacetate. In the drug rele ase system studied chlorine was a unique component of the drug, the po lymeric matrix was identified by its silicon component and the diffusi ng water labelled with deuterium. Areal distribution plots are shown f or differing exposure times of the polymer to D2O. The plots are also statistically analysed to show trends of increasing chlorine/deuterium correlation, silicon/deuterium anti-correlation and a constant silico n/chlorine anti-correlation with respect to time. (C) 1998 Elsevier Sc ience B.V. All rights reserved.