Abstract: A method to produce nanoporous microsponge particles useful as carriers for drug delivery. The method comprises a cross-linking/precipitation step wherein a cross-linking agent reacts with a biocompatible polymer having nucleophile functional groups, which react with said cross-linking agent. The cross-linking agent is prepared by a reaction between 1,1?-carbonyldiimidazole (CDI) and a diamine compound. The biocompatible polymer has an average molecular weight ranging from 10 KDa to 150 KDa.

Abstract: A method of making PVA microbubbles including a functionalisation step in which PVA polymeric chains are functionalised at their ends with aldehyde groups, and a subsequent cross-linking step, in which in an air-aqueous solution emulsion with a pH between 4.5 and 5.5 the previously functionalised PVA polymeric chains cross-link by means of an acetalisation reaction, thereby forming the microbubbles. The microbubbles produced are subsequently subjected to a lyophilising step, a filling step in which medicinal gas is introduced and a restoration step of the microbubbles by adding an aqueous solution.