Calcium Phosphate/DNA Co-Precipitates Encapsulated Fast-Degrading Polymer Films for Substrate-Mediated Gene Delivery

Calcium-phosphate/deoxyribose nucleic acid (Ca-P/DNA) co-precipitates were deposited on or encapsulated in fast-degrading polymer films with surface erosion degradation mechanism to mediate cell transfection. The polymer, cholic acid functionalized star poly(DL-lactide), was synthesized through the ring-opening polymerization of DL-lactide initiated by cholic acid. The releases of DNA from the Ca-P/DNA co-precipitates deposited film and the Ca-P/DNA co-precipitates encapsulated film were determined and compared. The in vitro gene transfections of HEK293 cells, Hela cells, and NIH 3T3 cells showed that the expression of pGL3-Luc plasmid could be effectively mediated by the Ca-P/DNA co-precipitates deposited and encapsulated polymer films. In addition, the films did not exhibit any additional cytotoxicity to the cells during the transfections, indicating that the fast-degrading polymer films have great potential in localized gene delivery. (C) 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 91B: 172-180, 2009