title: Silicalite nanoparticles that promote transgene expression.
abstract: Here, we report on a new zeolite-based silicalite nanoparticle that can enhance the transfection efficiencies generated by poly ethylene imine-plasmid DNA (PEI-pDNA) complexes via a sedimentation mechanism and can enhance the transfection efficiencies of pDNA alone when surface functionalized with amine groups. The silicalite nanoparticles have a mean size of 55 nm. Functionalizing the silicalite nanoparticles with amine groups results in a clear transition in zeta potential from -25.9 ± 2.3 mV (pH 7.4) for unfunctionalized silicalite nanoparticles to 4.9 ± 0.7 mV (pH 7.4) for amine functionalized silicalite nanoparticles. We identify that silicalite nanoparticles used to promote non-viral vector acceleration to the cell surface are found in acidic vesicles or the cytoplasm but not the nucleus. An MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide) assay showed that the silicalite nanoparticles were non-toxic at the concentrations tested for transfection. We show that surface functionalization of silicalite nanoparticles with amine groups results in a significant (230%) increase in transfection efficiency of pDNA when compared to unfunctionalized silicalite nanoparticles. Silicalite nanoparticles enhanced pDNA-PEI induced transfection of human embryonic kidney (HEK-293) cells by over 150%.
authors.affiliation: Division of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242, USA.
authors.forename: Megan E
authors.initials: ME
authors.lastname: Pearce
authors.forename: Hoang Q
authors.initials: HQ
authors.lastname: Mai
authors.forename: Namhoon
authors.initials: N
authors.lastname: Lee
authors.forename: Sarah C
authors.initials: SC
authors.lastname: Larsen
authors.forename: Aliasger K
authors.initials: AK
authors.lastname: Salem