The Firefly luciferase/Renilla luciferase luminescence intensity ratio (FRR) was calculated. To quantify gene knockdown, the FRR from cells transfected with siRNA polyplexes containing anti-Firefly luciferase (GL2 + GL3) siRNA were compared with identical polyplexes containing a negative control siRNA. All values Inhibitors,research,lifescience,medical shown on Figure 1 are relative to the firefly luciferase expression of cells transfected with a negative control siRNA sequence. Relative firefly luciferase expression (%) = FRR of cells transfected with siRNA polyplexes containing anti-Firefly/FRR of cells transfected

with negative control siRNA polyplexes. Figure 1 Effect of nanoparticle/siRNA (N/P) ratio on the transfection efficiency of all materials in CHO-K1 (a) and HeLa (b) Inhibitors,research,lifescience,medical cell lines. Values represent mean ± standard error of the mean (SEM) from three independent transfections. Triplicates were normalized … For anti-Firefly

siRNA transfection using PEI-M/SiO2, PHMBG and PHMBG-M/SiO2 as carriers, the Firefly/Renilla plasmids DNA were first transfected using PEI. The cells were grown as previously described. At the same time of plating, the PEI-DNA complex was added to each well. PEI-Firefly/Renilla plasmids DNA complexes were prepared as follows: 10μL Inhibitors,research,lifescience,medical of PEI stock solution (0.9mg/mL) was mixed with 6.0μg of Firely luciferase DNA, 1.0μg of Renilla luciferase

DNA and resuspended in OptiMEM Inhibitors,research,lifescience,medical I buffer. The mixture was kept at room temperature for 1h prior to transfection. After 24h of transfection, the culture media were removed and the cells were washed with PBS. Then, fresh media and polymer/anti-Firefly siRNA Inhibitors,research,lifescience,medical complex were added to each well. The complexes of PEI-M/SiO2, PHMBG and PHMBG-M/SiO2, with anti-Firefly siRNA were formed by mixing the appropriate amount of polymer stock solution (0.9mg/mL) with 70pmol of firefly siRNA and OptiMEM buffer. The mixture was kept at room temperature for 30mins prior to transfection. Rolziracetam After 24h of transfection, cell lysates were formed and analyzed for luciferase activity as previously described. In vitro magnetofection was carried out applying a magnetic field under the MG-132 mw cell-culture plate to concentrate particles into the target cells, using the same procedure as described above with only minor modifications: cells were exposed to a magnetic field using the MagnetoFACTOR-96 plates (Chemicell GmbH, Berlin, Germany; magnetic field, 0.3 Tesla). 2.5. Cell Proliferation Assay 2.5.1. MTS For cell viability, the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was employed. Cells (40000 cells/well) were seeded into 96-well microtiter plates (100μL of penicillin free culture medium with 10% FBS).