Functional multilayered capsules for targeting and local drug delivery.

One of the key challenges in the field of bio-nanotechnology for drug delivery systems (DDS) is the development of nano- or micro-sized delivery carriers possessing both targeting functionalities for specific tissues or cells, and controlled release properties for encapsulated drug molecules, proteins and genes. Hollow capsules developed by layer-by-layer (LbL) assembly have attracted much attention over the past few years owing to their ability to be modified, their capacity to encapsulate a wide range of chemicals, and the variety of functionalities with which they can be enhanced. Current research on LbL capsules focuses on the development of functionalized capsules for specific targeting of cancer or immune cells, and on controlling their release properties by environmental stimuli. This review discusses recent advances in DDS using functional hollow capsules specific for the cellular and tissue-targeted delivery, as well as stimuli-responsive controlled release. DDS based on functional hollow capsules may contribute to the development of new nano-medicines.