Comprehensive Evaluation of Gene Expression in Negative and Positive Trigger-based Targeting Niosomes in HEK-293 Cell Line

An efficient gene delivery system has some critical factors that enhance the efficiency of nanocarrier. These factors are low production cost, high bioavailability, high encapsulation efficiency, controllable release, and targeting ability. Niosome (the nonionic surfactant vesicles) was considered as a promising gene delivery system. Niosome can increase stability and uptake of active agents. We used all mentioned factors in one optimized formulation entitled plasmid- loaded magnetic niosomes (PMN). To increase the bioavailability of niosomes, we used ergosterol (a natural lipid) instead of cholesterol in structure of niosome. Also, cetyl trimethyl ammonium bromide (CTAB) in different concentrations was used to improve encapsulation of plasmid and compared to niosomes that did not have CTAB (negative niosome). Afterward, magnetic nanoparticle (Fe3O4@SiO2) was synthesized and loaded into niosome to obtain targeting ability. Prepared formulations were evaluated regarding size, zeta potential, morphology, encapsulation of magnetic nanoparticles and plasmid (Pm-cherry-N1), release rate, and transfection efficiency.  Results demonstrated that optimum formulation (Nio/CTAB3%/Fe/P) has a nanometric size (118 ± 2.31 nm, positive zeta potential (+25 ± 0.67 mV), high loading of plasmid (72%), and good gene expression (35%). Interestingly, after applying a magnetic field below the cell plate, we obtained ac increased gene expression from 35% to 42%. These results showed that this new formulation would have a promising future and also can be used for delivering the other drugs and active agents.