Research paper
A new approach for determination of powder wettability

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Abstract

Based on the work initiated by Shanker, R.M., Baltusis, P.J. and Hruska, R.M. (Development of a new technique for the assessment of wettability of powders. Pharm. Res., 11 (Suppl) (1995) s243 (abstract)) and Dove, J.W., Buckton, G. and Doherty, C. (Comparison of wetting behaviour of theophylline and caffeine using various contact angle measurement methods and inverse gas chromatography. In 15th Pharm. Technol. Conf., 19–21 March 1996, Oxford, UK), this study has focused on the determination of effectively wet perimeters during Wilhelmy plate immersion experiments of powder stuck on glue. Data generated from extrapolated immersion loads of plates in two different apolar liquids, enable a measure of powder wet perimeter. Such perimeters are used to derive contact angles of reference liquids on the particular powder. Two powders were taken as models: starch and ketoprofen.

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