Cationic solid-lipid nanoparticles can efficiently bind and transfect plasmid DNA.
The suitability of cationically modified solid-lipid nanoparticles (SLN) as a novel transfection agent was investigated. SLN were produced by hot homogenisation using either Compritol ATO 888 or paraffin as matrix lipid, a mixture of Tween 80 and Span 85 as tenside and either EQ1 (N,N-di-(beta-steaorylethyl)-N,N-dimethylammonium chloride) or cetylpyridinium chloride as charge carrier. The resulting particles were approximately 100 nm in size and showed zeta potentials around +40 mV at pH 7.4. DNA binding was tested by agarose gel electrophoresis. The resulting SLN-DNA complexes were further characterised by AFM and zeta potential measurements. Only the SLN batch SII-13, composed of 4% Compritol, 4% Tween/Span and 1% EQ1, was able to form stable complexes with DNA. Typical complexes were 300 to 800 nm in size. Cytotoxicity and transfection efficiency was tested in vitro on Cos-1 cells. Cationic SLN produced by modification with EQ1 were well tolerated, with LD50 values >3 mg/ml in the LDH release assay and >0.6 mg/ml in the WST-1 assay. Further, SLN-DNA complexes containing between 10 and 200 weight equivalents of SII-13 (matrix lipid) efficiently transfected the galactosidase expression plasmid pCMVbeta in the absence and presence of the endosomolytic agent chloroquine.
Olbrich
C
C
Department of Pharmaceutical Technology, Biopharmacy and Biotechnology, Free University of Berlin, 12169, Berlin, Germany.
Bakowsky
U
U
Lehr
C M
CM
Müller
R H
RH
Kneuer
C
C
D000818:Animals; D001665:Binding Sites / Q000235:genetics; D019556:COS Cells / Q000187:drug effects / Q000378:metabolism; D002412:Cations / Q000378:metabolism; D002470:Cell Survival / Q000235:genetics; D002594:Cetylpyridinium / Q000633:toxicity; D002738:Chloroquine / Q000633:toxicity; D004278:DNA, Superhelical / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity / Q000648:ultrastructure; D050356:Lipid Metabolism; D008055:Lipids / Q000235:genetics; D046911:Macromolecular Substances; D018625:Microscopy, Atomic Force; D008863:Microspheres; D010232:Paraffin / Q000633:toxicity; D010957:Plasmids / Q000235:genetics / Q000378:metabolism* / Q000633:toxicity / Q000648:ultrastructure; D013501:Surface-Active Agents / Q000633:toxicity; D014162:Transfection / Q000379:methods*
D002412:Cations; D004278:DNA, Superhelical; D008055:Lipids; D046911:Macromolecular Substances; D013501:Surface-Active Agents; D010232:Paraffin; D002738:Chloroquine; D002594:Cetylpyridinium