title: Efficient non-viral gene delivery mediated by nanostructured calcium carbonate in solution-based transfection and solid-phase transfection.
abstract: Among different non-viral gene delivery methods, the technique of co-precipitation of Ca(2+) with DNA in the presence of inorganic anions is an attractive option because of the biocompatibility and biodegradability. In this study, nano-sized CaCO(3)/DNA co-precipitates for gene delivery were prepared. The effect of Ca(2+)/CO(3)(2-) molar ratio on the gene delivery was investigated. The mechanism of the transfection mediated by CaCO(3)/DNA co-precipitates was studied by treatment of the cells with chloroquine, wortmannin and cytochalasin D, respectively. The in vitro gene transfections in different cells were carried out for both solution-based transfection and solid-phase transfection. The gene expression of the calcium carbonate based approach is strongly affected by the Ca(2+)/CO(3)(2-) ratio because the size of CaCO(3)/DNA co-precipitates is mainly determined by the Ca(2+)/CO(3)(2-) ratio. In addition, the encapsulation efficiency of DNA increases with decreasing Ca(2+)/CO(3)(2-) ratio. With a suitable Ca(2+)/CO(3)(2-) ratio, CaCO(3)/DNA co-precipitates could effectively mediate gene transfection with the expression levels higher than that of Lipofectamine 2000 in the presence of serum. The mechanism study shows that CaCO(3)/DNA co-precipitates are internalized via endocytosis of the cells and macropinocytosis is the main route of internalization. Compared with the solution-based transfection, CaCO(3)/DNA co-precipitates in the solid-phase transfection exhibit a lower gene expression level. The calcium carbonate based approach has great potential in gene delivery.
authors.affiliation: Department of Chemistry, Wuhan University, Wuhan 430072, People's Republic of China.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Ren-Xi
authors.initials: RX
authors.lastname: Zhuo
authors.forename: Si-Xue
authors.initials: SX
authors.lastname: Cheng
mesh_terms: D002119:Calcium Carbonate / Q000737:chemistry*; D049329:Nanostructures; D010316:Particle Size; D012996:Solutions; D013499:Surface Properties; D014162:Transfection
chemical_list: D012996:Solutions; D002119:Calcium Carbonate