Construction of conductive hydroxyethyl cellulose/soy protein isolate/polypyrrole composite sponges and their performances

Abstract In the present study, we have in situ synthesized polypyrrole (PPy) on the hydroxyethyl cellulose/soy protein isolate (HEC/SPI) sponges to construct electro-conductive HEC/SPI/PPy composite sponges (EHSS-Pn, n༞0). The composite sponges were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), conductivity and mechanical tests. The results indicated that EHSS-Pn still exhibit homogenous inter-connected macroporous structure for cell adhesion, proliferation and metabolism, indicating that the incorporation of PPy didn’t break the original HEC/SPI sponge structure. The electrical conductivity and mechanical properties of the HEC/SPI sponge were improved significantly by the incorporation of PPy. Cytocompatibility and hemocompatibility of all the sponges were evaluated by a series of in vitro experiments. The results of MTT assay and cell direct contact tests showed that the introduction of PPy didn’t cause any cytotoxicity and EHSS-Pn had good biocompatibility. Moreover, EHSS-Pn had good hemocompatibility and no significant side effects on the anticoagulant whole blood with the introduction of PPy. Therefore, the electro-conductive EHSS-Pn showed potential application in the tissue engineering field that requires electrical conductivity for stimulation or sensing such as neural tissue restoration.