Effect of chitosan-alginate nanoparticles and ultrasound on the efficiency of gene transfection of human cancer cells.

Background: Gene therapy has been used to treat a variety of health problems, but transfection inefficiency and the lack of safe vectors have limited clinical progress. Fabrication of a vector that is safe and has high transfection efficiency is crucial for the development of successful gene therapy. The present study aimed to synthesize chitosan-alginate nanoparticles that can be used as carriers of the pAcGFP1-C1 plasmid and to use these nanoparticles with an ultrasound protocol to achieve high efficiency gene transfection.

Methods: Chitosan was complexed with alginate and the pAcGFP1-C1 plasmid at different charge ratios to create chitosan-alginate-DNA nanoparticles (CADNs). The average particle size and loading efficiency were measured. Plasmid DNA retardation and integrity were analysed on 1% agarose gels. The effect of CADNs and ultrasound on the efficiency of transfection of cells and subcutaneous tumors was evaluated.

Results: In the CADNs, the average size of incorporated plasmid DNA was 600-650 nm and the loading efficiency was greater than 90%. On the basis of the results of the plasmid DNA protection test, CADNs could protect the transgene from DNase I degradation. The transgene product expression could be enhanced efficiently if cells or tumor tissues were first given CADNs and then treated with ultrasound.

Conclusions: The use of CADNs combined with an ultrasound regimen is a promising method for safe and effective gene therapy.