Biomedical Engineering Reference
In-Depth Information
4.6.5 Polycarbonates
Polycarbonates provide an attractive option for use as gene delivery vectors
owing to their biocompatibility and ease of incorporating functional moieties.
In the area of gene delivery, the use of carbonate-based polymers has been less
widely reported. Therefore, this versatile class of synthetic polymer presents a
very attractive option in the design of novel biodegradable gene delivery
vectors. Ong et al. described an approach to synthesize cationic biodegradable
polycarbonates by an organocatalytic ring-opening polymerization of func-
tional cyclic carbonates containing alkyl halide side chains, followed by a
subsequent functionalization step with bis-tertiary amines designed to facilitate
gene binding and endosomal escape.
119
The results showed that polycarbonate
mediated high luciferase gene expression in HepG2, HEK293, MCF-7, and
4T1 cell lines in the presence of serum, and low cytotoxicity.
Wang et al. synthesized PEI-grafted polycarbonates (PMAC-g-PEIx)as
biodegradable polycationic gene vectors (Scheme 4.17A).
120
A backbone
polymer, poly(5-methyl-5-allyloxycarbonyl-trimethylene carbonate) (PMAC),
was synthesized in bulk, catalyzed by immobilized porcine pancreas lipase
d
n
4
y
3
n
g
|
3
Scheme 4.17
Synthesis of PEI-grafted polycarbonates.
