Spray congealing is a low cost, simple and versatile method to produce microparticles without the use of organic or aqueous solvent. This review provides a detailed picture of the pharmaceutical applications of this technology, with an overview of the spray-congealed-based drug-delivery systems. First, the basic principles and equipment of spray congealing technology are presented. Then, representative examples of the drug-delivery systems are examined and critically discussed. Emphasis is given on the role of formulation variables, together with practical considerations for formulation design. In addition, the current status of the industrial applications of this technology within the pharmaceutical field is examined. The final part points out benefits, limitations and future perspectives of this technology in drug delivery.
Keywords: microencapsulation; multiparticulate drug-delivery systems; solid dispersion; solid lipid microparticles; solvent-free technology; spray chilling; spray cooling.