Cationic Polymers for the Delivery of Therapeutic Nucleotides - Nanotechnology for the Delivery of Therapeutic Nucleic Acids - page 44

considered to determine the most suitable one for the development
of PLA cNP as DNA carriers. Cationic PLA-PEI, PLA-chitosan, and
PLA-pDMAEMA nanoparticles were compared for interaction with
pDNA and its biological properties of bound DNA. The highest
transfection efficiency in cell culture was obtained with PLA-
pDMAEMA carriers.

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formulated DNA nano-
carriers of biodegradable polyesters consisting of amine modified
poly(vinyl alcohol) (PVAL) backbones grafted with PLGA. Amine
modified high MW biodegradable polyesters combining specific
characteristics, such as electrostatic interactions between DNA and
facilitating loading of DNA.

Similarly, Oster et al.

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2.3.5.2 Poly(amino ester)s
For the maximum and novel use of polyesters in therapeutic
applications, biodegradable cross-linked poly(amino ester)s have
been developed and used as non-viral vectors for gene delivery.
They are biodegradable and non-toxic cationic polymer deliberated
in terms of molecular mass, polymer end groups, complex size, and
N/P ratio (i.e., ratio of protonatable polymer amine groups to nucleic
acid phosphate groups).
Poly(amino ester)s have shown great potential with good
transfection efficiencies and low cytotoxicity

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and
can be divided into two types, linear poly(amino ester)s containing
tertiary amines in their backbones and hyperbranched poly(amino
ester)s containing tertiary amines in the core and primary amines at
the periphery. Poly(amino ester)s of different structures containing
primary, secondary, and tertiary amines are desirable, because
different types of amines play various roles such as the condensation
of DNA and forming the pH-buffering “proton sponge” to facilitate
escape of vectors from lysosomes.

in vitro like PEI

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reported a novel biodegradable poly(ester amine)
copolymer prepared from low MW PEI (2 kDa) and poly(L-lactide)
copolymers. Prepared copolymers showed a good ability to cond-
ense pDNA effectively into nanocomplexes with a small particle size
(~150 nm). Results obtained indicate potential application for such
poly(ester amine) as a gene delivery system.

Guo et al.

Further, degradable,
hyperbranched poly(ester amine)s based on poloxamer diacrylate
and low MW branched PEI were successfully synthesized and
evaluated as a gene carrier by Kim

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These poly(ester amine)s
showed good DNA binding ability with sizes of complexes below

et al.