Fig 1.
Synthesis and putative structure of OTMCS-PEI-R18.
Fig 2.
1H NMR spectra of (A) OTMCS-PEI and OTMCS-PEI-R18.
Fig 3.
MALDI-TOF mass spectra of (A) OTMCS-PEI and (B) OTMCS-PEI-R18.
Fig 4.
Determination of buffering capacity of the OTMCS-PEI-R18 polymer by acid-base titration.
Solution containing the polymer (0.2 mg/mL) was adjusted to pH 10.0, and then titrated with HCl from 10.0 to 3.0.
Fig 5.
Particle size and Zeta potential of OTMCS-PEI-R18/DNA at various w/w ratios.
The average diameter gradually decreased (A) and the Zeta potential gradually increased (B) as the ratio of conjugated DNA increased.
Fig 6.
Agarose gel electrophoresis of plasmid DNA and OTMCS-PEI-R18 /DNA complexes.
Agarose gel electrophoresis of OTMCS-PEI-R18-h/DNA(A) and OTMCS-PEI-R18-l/DNA(B) complexes at various w/w ratios, respectively. (C) Protection of plasmid DNA from degradation by DNase I at different concentrations of 0, 3, 6, 9, 18, 27, 36, 45, 54 and 63 U DNase I/μg DNA. (D) Protection of plasmid DNA from dissociation by sodium heparin at varying concentrations of 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200 μg/mL.
Fig 7.
The cytotoxicity of OTMCS-PEI-R18.
(A) Degradation of OTMCS-PEI-R18. (B) Cytotoxicity of OTMCS-PEI-R18 and other PEI derivates at various concentrations in Hela cell line using the MTT assay. OTMCS-PEI-R13, OTMCS-PEI and PEI 25 KDa were used as controls.
Fig 8.
Gene transfection efficiency of OTMCS-PEI-R18/DNA polyplexes.
(A) Representative fluorescence images for transfection in Hela cells using OTMCS-PEI-R18 at w/w ratios of 5, 10, 20, and 30. (B) Transfection efficiency of OTMCS-PEI-R18/DNA complexes in Hela cell line at w/w ratios of 5, 10, 20, and 30.
Fig 9.
The intracellular distribution of complexes OTMCS-PEI-R18/DNA.
(A) Fluorescent confocal microscopic images of Hela cells treated with FITC-labeled OTMCS-PEI-R18 polyplexes for 0.5 h, 1 h and 2 h, where the FITC-labeled OTMCS-PEI-R18 was shown in green, and the HE stained nuclear was shown in blue. (B) Inhibitory effect of different concentrations of Paclitaxel (PTX), Colchicine (Col) and Acrylamide on transfection efficiency of OTMCS-PEI-R18/DNA complex in Hela cells at w/w ratio of 30. The RLU/mg protein in control cells was set to 100%.
Fig 10.
Transfection efficiency of pGL3-Control as a reporter gene in mice.