Colloidosomes: An emerging vesicular system in drug delivery

The application of colloidal and nanoparticulate carrier systems in the biomedical field has changed the definitions of diagnosis, treatment, and disease management. Carrier systems such as liposomes, polymeric particles, and microemulsion droplets are used for the sustained release of drugs, pesticides, fragrances, and other substances. Although such delivery systems are widely employed in specialized areas such as gene delivery, targeting to brain, tumor targeting, and oral vaccine formulations, problems associated with their stability and permeability are often encountered, thereby limiting their general application. In the series of vesicular systems, colloidosomes are emerging as a potential tool for controlled delivery of drugs as well as of cosmetics and food supplements. Colloidosomes are solid microcapsules formed by the self-assembly of colloidal particles at the interface of emulsion droplets. Colloidosomes offer precise control over their size, permeability, compatibility, and mechanical strength and can be prepared with an aqueous, aqueous gel, or oily core. This review focuses on the types, fabrication techniques, and stability of colloidosomes.