Coacervates chemical nature

The coacervation approach uses heating or chemical denaturation and desolvation of natural proteins or carbohydrates. As much as 85% of water-soluble drugs can be entrapped within a protein matrix by freeze-drying the emulsion prepared in this manner. For water-insoluble drugs, a microsuspension-emul-sion procedure has been suggested as a method of choice to achieve high drug payloads. 

All of the materials containing two polymers can be broadly classified as either polymer blends or graft copolymers on the basis of the absence or presence of covalent chemical bonds between the two species. For special purposes, it has also been of interest to mix solutions of anionic and cationic polymers. Such materials coacervate, and form association complexes with ionic bonds. Because of the impermanent nature of such bonds, we choose to classify such materials with polymer blends. Examples of these materials are given by Leitz and Shorr (1972) and Eisenberg and King (1972). These materials are sometimes of interest because of their salt transport properties (Leitz and Shorr, 1972). See Section 9.5. 

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