Spray congealing: applications in the Pharmaceutical Industry
In this work, the potential of spray congealing in microencapsulation, taste masking and controlled release was explored and compared to other commonly used technologies, specifically spray drying and hot melt extrusion. The ability to control powder characteristics without the need of subsequent downstream processing methods is a marked advantage over other “particle-engineering” technologies. Moreover, spray congealing is an environmentally friendly process where high throughputs can be achieved. This technology involves some critical stages that should be thoroughly evaluated when establishing the process, namely the atomization, cooling and feed stages. Spray congealing represents a very attractive and promising platform to address some of the challenges related to drug development and drug life cycle management.
The increasing demand for new formulations as part of drug life cycle management or to address New Chemical Entities challenges is boosting the use of spray congealing, which can be described as a combination of spray drying and hot melt extrusion techniques. This platform can match many of the systems prepared by spray drying or hot melt extrusion but also enables the preparation of powders with unique properties and applications in microencapsulation, taste masking and controlled release. The main goal of this paper is to provide an overview on the applications of spray congealing in the pharmaceutical industry and compare this technology, presenting the advantages and drawbacks, with others more commonly used like spray drying and hot melt extrusion.
Spray congealing, also called spray chilling or spray cooling, is a unit operation in which a liquid melt is atomized in to a cooling chamber. A sufficiently cold gas stream enters the chamber, typically in co-current configuration, i.e. flowing in the same direction, contacting the droplets and solidification takes place. This involves the transformation of molten droplets from liqui ...