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Abstract: The mean crystal size, the suspension density and the liquid concentration are the three most important process parameters to quantify the progress of industrial crystallization processes. It will be shown that these parameters can be in-line monitored simultaneously by means of an ultrasonic crystallization monitoring technique (UCM), which will be introduced here in a proof of concept. This process analytical technology (PAT) differs from the known ultrasonic attenuation spectroscopy (UAS). For the UCM the ultrasonic velocity and attenuation were correlated and related to characteristic events during a crystallization process measured at only one frequency (no spectra of frequencies as it is used for UAS). The results shown in this study prepare the ground to establish the UCM as a simple, less complex, robust, universal applicable, inexpensive and, therefore, a winning alternative PAT to monitor and control in-line the solid as well as the liquid phase in the industrial crystallization by means of only one measuring device with two sensors. [Copyright &y& Elsevier]

Abstract: The coating of pharmaceutical compounds is a field of high interest. As most of the coating materials form an amorphous layer around the material, the studies on crystalline coatings are rare. In this work the progress in this domain should be summarized and innovative results concerning crystalline hollow needles as coating material are presented. Since the first reports on needles formed via a solvent-mediated phase transition from solvates to hydrates, the field could be widened to hydrate-to-anhydrate and anhydrate-to-hydrate transformations. Novel investigations on hollow theophylline monohydrate and carbamazepine dihydrate needles are presented. It is shown that the inclusion of substances into the hollow needle crystals is feasible by simple means, which enable an application in industry as coating for sensitive materials. [Copyright &y& Elsevier]