Protamine sulfate–calcium carbonate–plasmid DNA ternary nanoparticles for efficient gene delivery
Abstract
Ternary nanoparticles, protamine sulfate–calcium carbonate–plasmid DNA (PS–CaCO3–DNA), were prepared for efficient gene delivery. By adding the cationic polypeptide PS in the co-precipitation system of calcium carbonate and DNA, PS–CaCO3–DNA nanoparticles could be formed by self-assembly facilely. The effect of PS on the properties of the ternary nanoparticles was studied by varying the PS amount in the nanoparticles. The size and ζ-potential measurements indicated that the ternary nanoparticles with an appropriate PS amount exhibited a decreased size and an increased ζ-potential. The in vitro gene transfections mediated by different nanoparticles in 293T cells and HeLa cells were carried out in the presence of 10% fetal bovine serum, using pGL3-Luc and pEGFP-C1 as reporter plasmids. As compared with both PS–DNA nanoparticles and CaCO3–DNA nanoparticles, PS–CaCO3–DNA nanoparticles exhibited significantly enhanced gene delivery efficiency, which was higher than that of Lipofectamine 2000–DNA. Confocal microscopy observation showed that PS–CaCO3–DNA nanoparticles could efficiently deliver DNA to cell nuclei. These results indicated that the ternary PS–CaCO3–DNA nanoparticles prepared in this study have promising applications in gene delivery.