PROCESS-CONTROL AND END-POINT DETERMINATION OF A FLUID-BED GRANULATION BY APPLICATION OF NEAR-INFRARED SPECTROSCOPY

In the pharmaceutical industry, fluid bed granulation processes requir e tight control to ensure reliability. This is particularly the case w hen the product characteristics add to make the process intrinsically non-robust. Tight process control is generally achieved by careful and accurate control and monitoring of the process parameters affecting t he granule wetting/drying equilibrium. However, these parameters are p rone to natural unavoidable variation, causing variable and difficult to determine granulation end-points. Obtaining an immediate measure of a critical product characteristic during processing could help by lea ding to further improvements in process reliability. The application o f in-line near infra-red spectroscopy (NIRS) to obtain granule moistur e content and particle size change data is described. The technique is capable of monitoring the fluid bed process in 'real time', allowing modification of process conditions if required and end-point identific ation. This should lead to more optimum product characteristics and gr eater process reliability. (C) 1997 Elsevier Science B.V.