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 X-ray diffraction, scanning electron microscopy, 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 obvious side effects on the as-prepared anticoagulant whole blood after 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.

High internal stresses, solid solution sub-stable phases and many microscopic defects are generated during laser directed energy deposition (LDED)-assisted N2 in situ preparation of cermets on the surface of titanium alloy workpieces. The aim of this study is to gain insight into the structural evolution of in-situ prepared cermet materials by hot isostatic pressing treatment. Under high temperature and pressure, the dislocation cell structure serves as the nucleation site for phase transition and phase precipitation. The phase transformation and diffusional relaxation of metallic α′-Ti martensite formed the homogenized α/β-Ti, which improves plastic toughness. The solid solution N atoms use dislocations as diffusion channels to realize the reaction precipitation of the ceramic phase, and improve the strength of the cermet modified layer. The TiN/Ti interface structure is coherent interface of amorphous transition, which can improve the interface bonding strength and effectively transfer plastic deformation. The strength-plasticity balance of in-situ cermet materials is achieved by hot isostatic pressing treatment.