Preparation of poly(DMA-co-DBA) and its application in gene delivery

Abstract

(2-dimethyl amino)ethyl methacrylate (DMA) was co-polymerized with (2-dibutyl amino)ethyl methacrylate (DBA) to form random copolymer P(DMA-co-DBA) with DMA/DBA molar ratios in the range of 9:1 to 1:9 by Atom Transfer Radical Polymerization (ATRP). The (co)polymers were characterized with techniques such as GPC, ¹HNMR and acid-base titration. The cytotoxicity of the polymers was assessed by MTT. Size and zeta potential of P(DMA-co-DBA)/DNA polyplex were analyzed by dynamic light scattering. In vitro gene transfection was performed for P(DMA-co-DBA)/DNA polyplex in the medium with and without serum. In comparison with PDMA/DNA and PEI/DNA, P(DMA-co-DBA) 8:2/DNA showed much higher transfection efficiency than those of PDMA/DNA and PEI/DNA within the range of 0.125 − 1.25 μg·mL⁻¹ of DNA concentrations in the medium with 10% FBS. Confocal images showed that P(DMA-co-DBA) 8:2/DNA was superior to PDMA/DNA and PEI/DNA in the speed and capacity for endosomal release, which might be the main cause of its higher transfection efficiency.

Graphical abstract

Keywords:

• Cationic polymers
• endosomal release
• gene delivery
• hydrophobicity
• P(DMA-co-DBA)
• transfection efficiency

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, [S. Ding], upon reasonable request.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under [Grant 21174046 and 51174096].