USE OF NMR IMAGING IN THE OPTIMIZATION OF A COMPRESSION-COATED REGULATED RELEASE SYSTEM

Nuclear magnetic resonance (NMR) imaging is routinely used to detect t he protons of mobile water molecules within samples. In this investiga tion, this non-destructive, non-invasive technique was used to determi ne the cause for faster than predicted drug release from a dissolution -based regulated-release tablet. The NMR images of tablets, from mio d ifferent formulations, taken at various intervals of time while immers ed in static USP dissolution medium showed that the tablet with faster than predicted drug release had a porous coating. The porous coat exp osed more of the core surface area to the dissolution medium than desi red and this caused an increase in the rate of dissolution of the core . The data presented in this paper demonstrate the usefulness of NMR i maging in solid dosage form development. (C) 1998 Elsevier Science B.V .