Tablet Coating Methods for Very Small Batches and Their Suitability for Scaling-Up

Abstract

AbstractThree different laboratory-scale coating devices* were tested for their performance in terms of coating very small batches of solid dosage forms. The need for this study arose from a new film-forming material for colon-targeting which is available only in very small amounts. Particular attention should be paid to the subsequently planned scaling-up procedures. The following properties should be achieved: Homogeneous and smooth surfaces, as well as an overall equal film thickness obtained under controlled spraying rates of the coating solution, and determined flow-rates of the drying air. The obtained results show that all three units are principally suitable. The Huttlin HKC provides a unique small, variable working segment by subdividing the spherical coating chamber by installing two vertical partition walls. In such reduced coating segments very similar coating conditions, and practically similar material movements were observed, in spite of reducing the batch size as far as possible.