Biomedical Engineering Reference
In-Depth Information
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Scheme 4.14
Schematic illustration of (A) PAA-HIS and (B) a ternary polyplex.
cytotoxicity and achieve enhanced transfection efficiency.
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In addition, Nimesh
et al. showed polyallylamine complexed with dextran and DNA could
simultaneously improve upon transfection efficiency and cell viability.
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Recently, Chung et al. reported the preparation and characterization of ternary
nanoparticles with a negative surface charge, which comprises a histidine-
conjugated polyallylamine (PAA-HIS)/DNA core complex and a single-stranded
oligonucleotide outer layer, to transfect various cell lines (Scheme 4.14).
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As a continued effort, the same authors reported their investigations on the
endocytotic mechanisms involved in the uptake of the oligonucleotide-coated
PAA-HIS/DNA complexes.
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The results indicated that the oligonucleotide-
coated PAA-HIS/DNA complexes could specifically recognize adenosine
receptors on the cell surface and were taken up by an adenosine receptor-
mediated process. After receptor/ligand binding, oligonucleotide-coated PAA-
HIS/DNA/complexes were mainly internalized via a caveolae-mediated
pathway to result in effective intracellular processing for gene expression.
4.6.3 Linear Poly(amidoamine)s
Recently, linear poly(amidoamine)s, which can be easily synthesized by the
polyaddition of primary monoamines or bis(secondary amines) to bisacrylamides,
have attracted researchers' attention. Peng and co-workers reported the synthesis,
transfection, and intracellular trafficking characteristics of poly(amidoamine)s
with a pendant primary amine in the delivery of plasmid DNA to bone marrow
stromal cells (BMSCs).
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It was found that poly(amidoamine)s with a pendant
aminobutyl group demonstrated higher transfection efficiency and percentage of
