Fabrication of extracellular matrix-coated conductive polypyrrolepoly(L-lactide)fiber-films and their synergistic effect with(nerve growth factor)/(epidermal growth factor) on neurites growth

Non-nerve cell-derived extracellular matrix(ECM)wa s coated on the aligned porous polypyrrole-poly(Llactide)(PPy-PLLA)fiber-films with the conductivity of^12 mS/m via L929 cells culture and lysing,resulting in^10%increase of PC12 cells attachment and^26μm increase of neurites length.The neurite length of^149μm in EGF/NGF group(optimal concentration radio of 12.5/50(ng/mL))on aligned and ECM-conjugated fiber-films was significantly larger than^94μm in only NGF group(50 ng/mL),confirming the synergy of EGF,NGF and aligned ECM-conjuaged PPy-PLLA fibers.When differentiated PC12 cells were exerted electrical stimulation(ES)of 100 mV/cm for 4 h/day in 2 day through ECM-PPyPLLA fiber-films,their neurite length reached to^251μm,significantly larger than^149μm of group without ES,due to the higer expression of related neural proteins in ES group.A simple mechanism was proposed to analyze synergistical effect of ECM,EGF,NGF on axons adhesion and elongation along the aligned ECM-coated fibers under ES condition.