Cell transfection is a technique for introducing foreign molecules such as DNA, RNA, etc. into eukaryotic cells. Cationic polymer gene transfection technology is a cell transfection method introduced internationally in recent years. It is favored by researchers because of its wide application range, simple operation, low cytotoxicity and high transfection efficiency. Principle of cationic polymer gene transfection technology A common feature in the structure of cationic polymers is that there are more amino groups in the molecule. At physiological pH, these amino groups will be protonated, and these protonated amino groups can neutralize the negative charge on the surface of the DNA plasmid, so that the DNA molecule can be compressed into relatively small DNA particles from the stretched structure, or the target gene can be wrapped in it. This protects the DNA from degradation by nucleases. Therefore, they can be used as gene carriers. The positive charges on the surface of the cationic polymer interact with the negatively charged phosphate groups on DNA to form a cationic polymer-DNA complex. Cationic polymer-DNA complexes mainly transfer DNA into cells through endocytosis to form inclusion bodies. After that, the DNA is released from the inclusion body, enters the cytoplasm, and then further enters the nucleus for transcription and expression.

Figure 1. Examples of cationic polymers used in gene delivery systems. (Fus-Kujawa A, et al.;2021)

Advantages of Cationic Polymer Gene Transfection Technology

As a relatively safe and efficient gene carrier, cationic polymers have broad application prospects in the fields of gene therapy and biological research. Compared with other forms of gene carriers, cationic polymer carriers have incomparable advantages:

• No immunogenicity, will not cause the body's immune response;
• The physiological behavior of the carrier can be controlled by controlling the particle size and surface properties;
• Molecular structure can be flexibly designed according to needs;
• The release of genetic material can be determined by the degradation rate of the polymer matrix.

Influence of the cationic properties of cationic polymers on their transfection properties

When cationic polymers are used as gene carriers, their cationic properties have the following effects on gene transfection efficiency:

• Provides the power to self-assemble with DNA, which is beneficial to protect DNA from degradation;
• Compressed DNA into complex particles smaller in volume than free DNA, facilitating entry into cells;
• Electrostatic repulsion occurs between the composite particles to stabilize the composite;
• Electrostatic attraction with cell membrane to promote complex endocytosis;
• Combined with negatively charged components of body fluids, it is not conducive to in vivo transport;
• Blocks the release of DNA, which is detrimental to the expression of coding genes.

The first four effects are beneficial to improve the transfection efficiency, while the latter two effects are not conducive to improving the transfection efficiency. In order to improve the transfection efficiency of cationic polymers as gene carriers, it is necessary to promote the beneficial effects of cationic properties and suppress their adverse effects. In addition, the cationic properties of cationic polymers are also one of the determinants of their cytotoxicity, and the positive charges carried by them can damage the membrane structure of cells, resulting in hemolysis for blood cells. CD BioSciences has unique technology to synthesize low toxicity and high efficiency cationic polymer carriers, which can meet various needs of transfection.

Our Advantage:

• Customized polymer transfection kits according to customer needs
• Provide various types of cationic polymer carriers for users to choose
• Different vector screening can be provided to determine the best transfection vector
• Professional design and service team to provide you with reliable service and technical support
• Timely feedback of technical reports

CD BioSciences focuses on developing transfection systems and customizing transfection reagents for gene transfection using our core technologies. Through our high-quality products and services, the effectiveness of your transfections can be greatly improved.

Reference

1. Fus-Kujawa A, et al.; An Overview of Methods and Tools for Transfection of Eukaryotic Cells in vitro. Front Bioeng Biotechnol. 2021, 9:701031.
2. Sun X, Zhang N. Cationic polymer optimization for efficient gene delivery. Mini Rev Med Chem. 2010,10(2):108-25.

* For research use only. Not for use in clinical diagnosis or treatment of humans or animals.