Case studies in blend sampling using a front-loading thief

In-process testing is employed in pharmaceutical systems for monitoring and detecting process failures. Blend sampling is a useful in-process test. The present article outlines case studies in which sampling thieves with front-loading and side-vented mechanisms were compared. Blend uniformity analysis (BUA) using a front-loading sampling thief helped confirm or discover blend homogeneity issues and guide the product development process to rational decision points by providing quick responses to actual or impending failure with a low probability of falsely declaring a failure that is not present.