Catalytic Synthesis and Characterization of Biodegradable ...
Catalytic Synthesis and Characterization of Biodegradable ...
Catalytic Synthesis and Characterization of Biodegradable ...
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Polymerization <strong>and</strong> Applications <strong>of</strong> <strong>Biodegradable</strong> Polyesters<br />
The solubility <strong>of</strong> polyaniline could be enhanced by covalently grafting side groups or<br />
polymers, such as poly(ethylene glycol), on the backbone <strong>of</strong> polyaniline. 135 Wei et al. 136<br />
demonstrated that the electroactive silsesquioxane precursor,<br />
N-(4-aminophenyl)-N'-(4'-(3-triethoxysilyl-propyl-ureido) phenyl-1,4- quinonenediimine)<br />
(ATQD), containing aniline trimer covalently modified by oligopeptide could be a kind <strong>of</strong><br />
promising biomaterial for tissue engineering. The bioactive material, ATQD-RGD, supported<br />
PC-12 cell adhesion <strong>and</strong> proliferation, <strong>and</strong> stimulated spontaneous neuritogenesis in PC-12<br />
cells in the absence <strong>of</strong> neurotrophic growth factors (NGF), as shown in Figure 1.5.10.<br />
Figure 1.5.11 (A) Representational fluorescence micrographs <strong>of</strong> PC-12 cell for the substrates (a)<br />
TCPS (-) without electrical stimulation, (b) TCPS (+) exposed to electrical stimulation, (c) EM<br />
PLAAP (-) doped with CSA without electrical stimulation, (d) EM PLAAP (+) doped with CSA<br />
exposed to electrical stimulation on day 4. (B) The mean neurite length <strong>of</strong> PC-12 cells cultured<br />
on the substrates <strong>of</strong> EM PLAAP (-), TCPS (+), <strong>and</strong> EM PLAAP (+) on day 4. 136<br />
Based on the above works, Chen’s group did many works to exp<strong>and</strong> the architecture <strong>of</strong> this<br />
kind <strong>of</strong> materials. They chose aniline oligomers (especially aniline pentamer with dicarboxyl<br />
end group (AP)) as electroactivity resource, which incorporated with degradable polymers,<br />
such as polylactide (PLA), poly(ε-caprolactone) (PCL) <strong>and</strong> natural biopolymer chitosan, to<br />
prepare new biodegradable electroactive biomaterials. 137-139 The introducing <strong>of</strong> PLA<br />
endowed the material with good electroactivity, solubility <strong>and</strong> biodegradability similar to<br />
pure PLA. In vitro cell evaluation showed that the electroactive copolymers could indeed<br />
promote the attachment <strong>and</strong> growth <strong>of</strong> rat C6 glioma cells. Moreover, in the comparison