Figure 2From: BMP2 gene delivery to bone mesenchymal stem cell by chitosan-g-PEI nonviral vectorStructure characterization of chitosan-g-PEI by FTIR spectra. The chemical structure of chitosan, chitosan-g-PEI, and PEI was shown (A). Their functional groups correspond to the representative bands on the FTIR spectra (B).Back to article page