Process Analytical Technology (PAT) Tool for In-line Measurement and Control of Tablet Coating Thickness
Terahertz waves have the unique ability to measure the coating thickness on individual tablets and to show the tablet to tablet variation.
TeraView has developed an in-line probe which, when placed into a tablet coating drum, can monitor and control the coating thickness on individual tablets. The ILOL3000 takes circa 100 readings per minute and hence can measure several thousand tablets over a full coating run. In real time this data can then be used to show the tablet to tablet variation and when integrated into the wider control system can control tablet coating thickness, end point and alarm if malfunctions occur.
By contrast to with other techniques, the reading is absolute and hence avoids the need for a complicated chemometric model. The type and thickness of the coating is not an issue, with detection limits ranging from 30 microns to several mm.
The unit is currently being further developed to measure other properties such as density, moisture and Interface Index (a parameter used to quantify the level of adhesion between two layers). The off line TPI imaga 2000 has already shown the importance of these and the ability to measure them.
The new in-line system compliments TeraView's existing off line TPI imaga 2000 which generated 3D images of individual tablets. For controlled or modified release products, these images have often been shown to correlate the products performance. The TPI imaga 2000 has proven to be a key tool in the design of such products, helping to identify and quantify critical quality attributes (CQA’s). The in-line ILOL3000 is key in the measurement of these during process development, scale-up and ultimately manufacture.