Synthesis of Novel Biodegradable Cationic Polymer:  N,N-Diethylethylenediamine Polyurethane as a Gene Carrier

Abstract

A new cationic polymer, N,N-diethylethylenediamine-polyurethane (DEDA-PU), bearing tertiary amines in the backbone and side chains, was synthesized and used as a nonviral vector for gene delivery. The DEDA-PU readily self-assembled with the plasmid DNA (pCMV-betagal) in water and buffer at physiological pH, as determined by agarose gel retardation, dynamic light scattering, zeta potential, atomic force microscopy (AFM), and restriction endonuclease protection assays. The results revealed that DEDA-PU was able to bind with plasmid DNA, yielding positively charged complexes with a size around 100 nm at a DEDA-PU/DNA ratio of 50/1 (w/w). The DEDA-PU/DNA complexes were able to transfect HEK 293 cells in vitro with an efficiency comparable to a well-known gene carrier [poly(2-dimethylaminoethyl methacrylate), PDMAEMA]. The cytotoxicity of DEDA-PU was substantially lower than PDMAEMA. The degradation studies indicated that DEDA-PU degrades hydrolytically in 20 mM HEPES buffer at pH 7.4 with a half-life of approximately 60 h. This study shows that DEDA-PU holds promise as biodegradable polycations for gene delivery and is interesting candidate for further study.

Synthesis and characterization of biocompatible, degradable, light‐curable, polyurethane‐based elastic hydrogels

“…Therefore, changing the ratio of PEG and PCL can adjust the ratio of water repellent and water absorbent groups in soft segments, and based on this principle, the hydrophilicity of the elastic biodegradable polyurethanes can be finely tuned accordingly for different biomedical applications. For example, polymers used for gene delivery system are generally required to be highly hydrophilic, 11,37 polymers used for wound dressing material need moderate hydrophilicity, 38 while polymers applied as the scaffold for the anterior cruciate ligament (ACL) reconstruction require low hydrophilicity. 9 Therefore, synthesis of elastic polyurethanes with adjustable hydrophilicity would expand their utility as candidate materials for a wide range of biomedical applications.…”

“…Several series of degradable polyurethanes have been developed for applica-tions including cardiovascular repair, ligament reconstruction, cancellous bone regeneration, and controlled drug delivery, among others. [9][10][11] Most degradable polyurethanes were developed by the introduction of labile moieties, such as caprolactone, 12 lactides, 13 hydroxybutyric acid, 14 saccharide, 15 or amino acids, 16 as either soft segments or chain extenders. The labile bonds can be broken in vivo either enzymatically or chemically, in most cases by hydrolysis.…”

Synthesis and Characterization of the Novel Transfection Reagent Poly(amino ester glycol urethane)

“…These polymers are incorporated with positively charged amine groups for DNA binding and are connected through hydrolytically unstable linkages such as ester or urethane linkages to induce biodegradability and generate nontoxic degraded compounds. [5][6][7][8][9][10][11] Additionally, cationic polymers would provide a pH-buffering ability, allowing a "proton sponge" to be formed, which would assist in the escape of vectors from the endocytosis pathway and improve transfection efficiency. [12][13][14][15] Among a variety of biodegradable polymers, poly(ester urethane) (PEU), has lately attracted interest as tissue-engineering scaffolds for its elastic, biodegradable, and cell-adhesive properties.…”

Synthetic and Natural Polycations for Gene Therapy: State of the Art and New Perspectives

“…Therefore, the ideal gene delivery system must be capable of protecting the DNA until it reaches its target. Poly(amidoammonium) salts Vuillaume et al, 2005., Richardson et al, 2001 Polyamine-dialkyl phosphate Dewa et al, 2004 Copoly(allyl glycidyl ether/ethylene oxide) Koyama et al, 2003 Poly[N-ethyl-4-vinyl pyridinium bromide] Gebhart et al, 2001 polyazobenzene dendrimer Atarashi et al, 2000 Block and graft copolymers of N-(2-hydroxypropyl)methacrylamide (HPMA) with 2-(trimethylammonio)ethyl meth acrylate Oupicky et al, 2000 Poly-N-(2-hydroxypropyl)methacrylamide-Poly(trimethylammonioethyl methacrylate chloride) Protamine Wagner et al, 1991Cyclodextrins Bellocq et al, 2003, Popielarski et al, 2003, Reineke and Davis, 2003, Pun et al, 2003Pullulan Yudovin et al, 2005Polyallylamine Boussif et al, 1999 Poly(ethylenimine-co-L-lactamide-co-succinamide) Petersen et al, 2002 N,N-diethylethylenediamine-polyurethane Yang et al, 2004 Poly(3-guanidinopropyl methacrylate) Funhoff et al, 2004Polyphosphoester Wang et al, 2001Ionenes Zelikin et al, 2002 β-cyclodextrin-containing polymers Hwang et al, 2001 Polyethylene glycol (PEG)-grafted (co)telomers Le Bon et al, 2002 Poly[α-(4-aminobutyl)-L-glycolic acid] Lim et al, 2000 Poly(4-vinylimidazole) Ihm et al, 2003 To do so, the system must be small enough to allow internalization into cells and passage to the nucleus, it must have flexible tropisms for applicability in a range of disease targets, and it must be capable of escaping endosomelysysome processing and of following endocytosis. Currently, gene therapy is being tested in many different health problems such as cancer, AIDS, and cardiovascular diseases, with mixed results, mainly owing to the inefficiency of the gene transfer vectors chosen.…”