The Effect of Linear PEI on Characteristics and Transfection Efficiency of PEI-Based Cationic Nanoliposomes

Document Type : Original Article


1 Pharmaceutical Research Centre, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran

2 Nanotechnology Research Centre, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran

3 Pharmaceutical Research Centre, Mashhad University of Medical Sciences, Mashhad, Iran


The development of efficient and safe carrier system to transfer DNA into cells is essential in non-viral gene therapy. The aim of the present study was to evaluate the effect of linear polyetheneimine (lPEI) (2500 Da) on the physicochemical and biological properties of lipopolyplexes constructed from liposomes and lPEI.
Materials and Methods
Different lipopolymers were synthesized from lPEI and acrylate derivatives. Nanocarriers were composed of the lipids (DOPE, DPPE and DOTAP) and the synthesized lipopolymers. After characterization of the prepared vectors by determination of size and zeta potential, transfection activity was tested in Neuro2A cells. Ethidium bromide and MTT test were used to evaluate the DNA condensation ability and cytotoxicity of vectors, respectively.
Vector’s size ranged from 95 to 337 nm and they had positive charge. The differences in DNA binding properties of lipopolyplexes were not significant. Among lipids, DOTAP showed better impact on transfection efficiency. The highest transfection activity was achieved by liposomal formulation consist of DOTAP and lipopolymer composed of lPEI and hexyl acrylate. The lipopolyplexes showed minimum cytotoxicity to the cultured cells in vitro.
The results of study confirmed that it is possible to improve gene expression using lipopolyplexes.


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