A mini review of biodegradable calcium phosphate nanoparticles for gene delivery.

Nucleic acid drugs are promising new therapeutics for the treatment of various diseases including genetic diseases, viral diseases, and cancer. However, their poor intracellular bioavailability and rapid degradation hinder their development as drugs. Therefore, the main challenge is to develop an efficient delivery system. Calcium phosphate has been widely used to transfect cultured cells for 40 years, due to its safety, simply of production and noticeable efficacy of transfection. Unfortunately, calcium phosphate particles show poor colloidal stability because of uncontrolled growth, which impedes their practical use. Recently, investigators have designed a variety of biodegradable calcium phosphate nanocarriers and achieved efficient gene delivery both in vitro and in vivo with low toxicity. In this review, we focus on the current research activity in the development of calcium phosphate nanoparticlss for gene delivery. Calcium phosphate nanoparticles are mainly classified into lipid coated and polymer coated ones for discussion. In addition, cellular uptake and intracellular trafficking of calcium phosphate nanoparticles are also mentioned.