Cationic Polymer Optimization for Efficient Gene Delivery

Abstract

The polyplexes which are formed between cationic polymers and DNA through electrostatic interactions and thus known as polycation/DNA complexes, are by far the most widely used non-viral gene delivery vectors. Many factors such as molecular weight, surface charge, charge density, hydrophilicity and the structure of cationic polymers affect gene transfection efficiency of cationic polymers. Therefore, optimization of cationic polymers is necessary to improve the gene transfection efficiency. Currently several important cationic polymers were used as cationic vectors for gene delivery which included PEI, PLL, Chitosan and PAMAM. Their most advantages and the rational design are introduced in this article. However, these systems are much less efficient in gene transfer experiments compared with viral systems. Some strategies such as PEGylation, combination and multifunctional modification were developed in the cationic polymeric vectors for gene delivery. Hereby, this article will review various kinds of copolymers with higher stability but biodegradable, bioresponsive and easy refined molecular weight which could be easily modification. Especially, the multifunctional modified polyplexes and polymersomes will be further discussion due to their ability to conjugate biologically active ligands, which can be used as potential nanostructured biomaterials for future in vivo gene delivery.

Strategies for Gene Transfer to Vascularized Composite Allografts

“…Cationic polymer vectors or, often termed, polyplexes (polycation/DNA complexes) are formed between cationic polymers and DNA through electrostatic interactions, which physically compact the DNA into a smaller structure. These types of compacted poly-charged structures are by far the most widely used nonviral gene delivery vector system [13].…”

Copolymer micelles function as pH-responsive nanocarriers to enhance the cytotoxicity of a HER2 aptamer in HER2-positive breast cancer cells

“…18,20,21 Nonviral systems, such as lipidor polymer-based approaches, have gained much attention due to their low cytotoxicity, Among the nonviral delivery systems, polymeric nanoparticles are an attractive option for gene therapy due to their unique properties including self-assembly behavior, ability to condense and protect nucleic acids, cell association, efficient cell transfection, and low cytotoxicity. 23,[25][26][27][28] Recently, the addition of stimuli-sensitive functions has enabled polymeric nanoparticles to specifically respond to pathological or externally applied "triggers" (eg, temperature, pH, enzymatic catalysis, and light or magnetic fields) and further extended their potential applications. [29][30][31][32] For example, pH-responsive polymeric nanoparticles capable of protecting nucleic acids in the blood circulation and actively releasing their cargo in the tumor microenvironment and/or inside the target tumor cells have received overwhelming interest in the context of cancer therapy.…”

Measurement of Reaction Rate between DNA and Polyethylenimine using Quartz Crystal Microbalance and Surface Plasmon Resonance

“…Non-viral gene delivery systems have attracted considerable attention as they have the potential to overcome these limitations [2]. Polyethylenimine (PEI) is one of the most effective polymers for non-viral gene delivery [3][4][5]. The efficient transfection of DNA by PEI is attributed to its property of condensing DNA molecules into nanoparticles.…”