| Current gene delivery strategies (both viral and non-viral) suffer from severe drawbacks including low transfection efficiency, poor cellular uptake and rapid in vivo degradation along with other effects such as immunogenic response and cytotoxicity. Microparticle based delivery of nucleic acids is a very promising approach for the effective transfer of genetic material into the phagocytic cells. There have been several approaches to deliver plasmid DNA based therapeutics by using microparticles, especially encapsulation of nucleic acids inside biodegradable polymeric microparticles. Though there are some promising results, there have been drawbacks regarding the degradation of the DNA due to the high speed shearing forces during the encapsulation and low encapsulation efficiency. On the other hand, the surface adsorption of DNA on cationic microparticles helps in efficiently targeting phagocytic cells, efficient loading of nucleic acids, and increase the bioavailability of the plasmid DNA. The LBL self-assembly process uses the concept of surface adsorption of DNA/polycation thin films on colloidal microparticles as a potent gene delivery mechanism. |
