Abstract:
:Branched polyethylenimine (PEI) chains with an average molecular mass of 2 kDa (PEI2) have been covalently attached to gold nanoparticles (GNPs), and the potency of the resulting PEI2-GNPs conjugates as vectors for the delivery of plasmid DNA into monkey kidney (COS-7) cells in the presence of serum in vitro has been systematically investigated. The transfection efficiencies vary as a function of the PEI/gold molar ratio in the conjugates, with the best one (PEI2-GNPII) being 12 times more potent than the unmodified polycation. This potency can be further doubled by adding amphiphilic N-dodecyl-PEI2 during complex formation with DNA. The resulting ternary complexes are at least 1 order of magnitude more efficient than the 25-kDa PEI, one of the premier polycationic gene-delivery vectors. Importantly, although unmodified PEI2 transfects just 4% of the cells, PEI2-GNPII transfects 25%, and the PEI2-GNPII/dodecyl-PEI2 ternary complex transfects 50% of the cells. The intracellular trafficking of the DNA complexes of these vectors, monitored by transmission electron microscopy, has detected the complexes in the nucleus <1 h after transfection.
journal_name
Proc Natl Acad Sci U S Aauthors
Thomas M,Klibanov AMdoi
10.1073/pnas.1233634100keywords:
subject
Has Abstractpub_date
2003-08-05 00:00:00pages
9138-43issue
16eissn
0027-8424issn
1091-6490pii
1233634100journal_volume
100pub_type
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