title: Cationic silica nanoparticles as gene carriers: synthesis, characterization and transfection efficiency in vitro and in vivo.
abstract: The potential of cationic SiO2 nanoparticles was investigated for in vivo gene transfer in this study. Cationic SiO2 nanoparticles with surface modification were generated using amino-hexyl-amino-propyltri-methoxysilane (AHAPS). The zeta potential of the nanoparticles at pH = 7.4 varied from -31.4 mV (unmodified particles; 10 nm) to +9.6 mV (modified by AHAPS). Complete immobilization of DNA at the nanoparticle surface was achieved at a particle ratio of 80 (w/w nanoparticle/DNA ratio). The surface modified nanoparticle had a size of 42 nm with a distribution from 10-100 nm. The ability of these particles to transfect pCMVbeta reporter gene was tested in Cos-1 cells, and optimum results were obtained in the presence of FCS and chloroquine at a particle ratio of 80. These nanoparticles were tested for their ability to transfer genes in vivo in the mouse lung, and a two-times increase in the expression levels was found with silica particles in comparison to EGFP alone. Very low or no cell toxicity was observed, suggesting silica nanoparticles as potential alternatives for gene transfection.
authors.affiliation: Department of Biopharmaceutics and Pharmaceutical Technology, Saarland University Saarbrücken, D 66123, Germany.
authors.forename: M N V
authors.initials: MN
authors.lastname: Ravi Kumar
authors.forename: M
authors.initials: M
authors.lastname: Sameti
authors.forename: S S
authors.initials: SS
authors.lastname: Mohapatra
authors.forename: X
authors.initials: X
authors.lastname: Kong
authors.forename: R F
authors.initials: RF
authors.lastname: Lockey
authors.forename: U
authors.initials: U
authors.lastname: Bakowsky
authors.forename: G
authors.initials: G
authors.lastname: Lindenblatt
authors.forename: H
authors.initials: H
authors.lastname: Schmidt
authors.forename: C M
authors.initials: CM
authors.lastname: Lehr
mesh_terms: D000818:Animals; D019556:COS Cells; D002412:Cations; D002738:Chloroquine / Q000737:chemistry; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000378:metabolism; D018014:Gene Transfer Techniques; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008027:Light; D008168:Lung / Q000378:metabolism; D051379:Mice; D008811:Mice, Inbred DBA; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry*; D017785:Photons; D010957:Plasmids / Q000378:metabolism; D012542:Scattering, Radiation; D012821:Silanes / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D013053:Spectrophotometry; D014162:Transfection; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D002412:Cations; D012821:Silanes; C495953:amino-hexyl-amino-propyltri-methoxysilane; D049452:Green Fluorescent Proteins; D012822:Silicon Dioxide; D002738:Chloroquine; D004247:DNA; D001616:beta-Galactosidase; D012825:Silicon