Application of a fluorescence sensor for miniscale on-line monitoring of powder mixing kinetics.

A portable system using light-induced fluorescence technology (LIF) was development as an analytical tool for on-line monitoring of various manufacturing process applications. The LIF system was verified in several laboratory scale process applications specifically in noninvasive real-time observations of blend kinetics in tumbler blenders. This technology, through careful selection of filters for specific formulations, can provide clean and unadulterated raw data that shows the actual blend characteristic behavior of powder mixtures such as homogeneity end point and blend stability. Consistent blend homogeneity end point was demonstrated for all runs with LIF where data were verified by thief sampling and UV spectrophotometric assays. A correlation between LIF signal and drug powder concentration was established with limits of detection below 0.02% w/w for the API, Triamterene. Copyright 2004 Wiley-Liss, Inc.