▎ 摘 要
Although electrical stimulation (ES) has been proved to be an effective strategy in promoting the regeneration and repair of injured peripheral nerve tissue, it is still a big challenge to encounter the risk of inflammation and infection when the conductive biological platform directly contacted with the damaged tissue. Therefore, it is a very promising solution to develop non-invasive flexible electrodes' bio-scaffolds for clinical treatment of nerve tissue regeneration combined with ES. With such purpose, the flexible composite electrodes by depositing polypyrrole on laser-induced graphene (LIG) have been developed. The proliferation and differentiation of PC-12 cells incubated on the prepared composite electrodes combined with an ES of 400 mV/cm at different times have also been investigated. The results showed that the fabricated composite electrodes exhibited excellent conductivity and wettability. Moreover, the essence of ES was to induce a field effect, namely, the cell proliferation was independent of the conductivity of the composite electrodes. In addition, we observed that ES could significantly enhance proliferation and differentiation of PC-12 cells. With the prolongation of ES time, the increasing trend finally stabilized. Importantly, the cell growth through MTT value was 1.37 when ES time was 4 h, and the increment was the largest, reaching 0.3, compared with that of 2 h. Furthermore, the cell differentiation showed that the neurite outgrowth length at 8 h of ES was the broadest distribution (the half-width ca 33.83 mu m). And the average neurite length reached 68.39 mu m after 8 h of ES, which increased by 16.26 mu m compared with that of 4 h. This work inspires the design and construction of a practical conductive platform, and provided a new theoretical basis and data support for clinical therapy in nerve tissue engineering combined with ES.