ABSTRACT
Another key advantage of using biodegradable microspheres as gene delivery vehicles is that they do not require surgical implantation or retrieval. Microspheres can be administered locally into a tissue by bolus injections or intravenously for systemic applications. Once injected, the
microspheres will degrade, the entrapped DNA will be released, and the released DNA will be available for transfection. The rate of polymeric degradation and thus the rate of DNA release is dependent upon the composition and formulation of the microspheres. Since a wide variety of polymers is available, microspheres offer flexibility in dosage and release kinetics.
