Fig. 2
Characterization of nanoparticle complexes. a 1H-NMR spectroscopy of the copolymers PP, FPP and DFPP. The peaks at 4.6–4.7 ppm were chemical shifts due to D2O. PP had peaks at 3.5–3.6 ppm (from PEG) and 2.4–3.0 ppm (from PEI). FPP and DFPP had extra peaks at 7.0–7.2 ppm due to the FSH peptides. b FTIR of the copolymers PP, FPP and DFPP. c The agarose gel electrophoresis assays of PP-shHK2, FPP-shHK2 and DFPP-shHK2 at different N/P ratios. d Transmission electron microscopy images of PP-shHK2, FPP-shHK2 and DFPP-shHK2. Scale bar, 500 nm