Cationic Silica Nanoparticles as Gene Carriers: Synthesis, Characterization and Transfection Efficiency <I>In vitro</I> and <I>In vivo</I>

Abstract

The potential of cationic SiO2 nanoparticles was investigated for in vivo gene transfer in this study. Cationic SiO2 nanoparticles with surface modification were generated using amino-hexyl-amino-propyltri-methoxysilane (AHAPS). The zeta potential of the nanoparticles at pH = 7.4 varied from -31.4 mV (unmodified particles; 10 nm) to +9.6 mV (modified by AHAPS). Complete immobilization of DNA at the nanoparticle surface was achieved at a particle ratio of 80 (w/w nanoparticle/DNA ratio). The surface modified nanoparticle had a size of 42 nm with a distribution from 10-100 nm. The ability of these particles to transfect pCMVbeta reporter gene was tested in Cos-1 cells, and optimum results were obtained in the presence of FCS and chloroquine at a particle ratio of 80. These nanoparticles were tested for their ability to transfer genes in vivo in the mouse lung, and a two-times increase in the expression levels was found with silica particles in comparison to EGFP alone. Very low or no cell toxicity was observed, suggesting silica nanoparticles as potential alternatives for gene transfection.

A Single Instillation of Amorphous Silica Nanoparticles Induced Inflammatory Responses and Tissue Damage until Day 28 after Exposure

“…Some researchers have reported that SiNPs that carry a positive charge are more likely to function as DNA carriers for gene transfection. 22,23) In the present study, the potential zeta value of SiNPs was −12.76 mV, and they entered into alveolar macrophages through nonspecific phagocytosis. We assume that SiNPs of positive charge may have different affinity for cell membranes to that of negatively charged SiNPs, so the toxicity between differently charged nanoparticles would also be different.…”

Maghemite Functionalization for Antitumor Drug Vehiculization

“…Moreover, it was found that cationic SiO 2 nanocomposites functionalized with amino-hexylamino-propyltrimethysilane exhibited no or very low cytotoxicity (De Jong & Borm, 2008). As can be noticed, no conclusive results have been reported, though, since they have been proved to be both toxic (Chang et al, 2007) and non-toxic (Ravi Kumar et al, 2004).…”

Preparation and characterization of chitosan and trimethyl-chitosanmodified poly-(ε-caprolactone) nanoparticles as DNA carriers

“…24 Investigations were performed to encapsulate DNA-cation-complexes into microspheres, but the preparation is complicated and yields microscaled particles. 25 Successful transfection in vitro and in vivo has been achieved with positively charged silica nanoparticles; 21,26 however, the fate of the inorganic carrier substance silica may remain a problem. In order to address this issue it was decided to develop nanoparticulate DNA carriers based on biodegradable polymers.…”