As a promising agent for biomedical application, collagen has been used as a nanofiber to architecturally mimic its fibrillar structure in Extracellular Matrix (ECM); however, it has to be modified by techniques, such as crosslinking, to overcome its limitations in structural stability along with potential toxicity. Here, we prepared collagen/polyethylene oxide (PEO) nanofibrous membranes with varying crosslinking degrees and their properties, such as water stability, mechanical properties, blood clotting capacity and cytocompatibility, were studied systematically. By investigating the relationship between crosslinking degree and their properties, nanofibrous membranes with improved morphology retention, blood clotting capacity and cytocompatibility have been achieved. The result of circular dichroism measurement demonstrated that a triple helical fraction around 60.5% was retained. Moreover, the electrospun collagen/PEO at crosslinking degrees above 60.6% could maintain more than 72% of its original weight and its nanofibrous morphology under physiological conditions could be well preserved for up to 7 days. Furthermore, the crosslinked collagen/PEO membrane could provide a more friendly and suitable environment to promote cell proliferation, and about 70% of the clot can be formed in 5 min. With its superior performance in water stability, hemostasis and cytocompatibility, we anticipate that this nanofibrous membrane has great potential for wound dressing.

An ideal hernia mesh is one that absorbs drugs and withstands muscle forces after mesh implantation. Polypropylene (PP) mesh devices have been accepted as a standard material to repair abdominal hernia, but the hydrophobicity of PP fibers makes them unsuitable to carry drugs during the pre-implantation of PP meshes. In this study, for the first time, one-step functionalization of PP mesh surfaces was performed to incorporate bio-inspired polydopamine (PDA) onto PP surfaces. All PP mesh samples were dipped in the same concentration of dopamine solution. The surface functionalization of PP meshes was performed for 24 h at 37 °C and 80 rpm. It was proved by scanning electron microscopic (SEM) images and Fourier Transform Infrared Spectroscopy (FTIR) results that a thin layer of PDA was connected with PP surfaces. Moreover, water contact angle results proved that surface functionalized PP meshes were highly hydrophilic (73.1°) in comparison to untreated PP mesh surfaces (138.5°). Thus, hydrophilic PP meshes with bio-inspired poly-dopamine functionalization could be a good choice for hernia mesh implantation.

Tubular braiding fabric is widely used in developing tissue-engineered scaffolds, and is especially suitable for connective tissues like ligaments and tendons. The pore size and porosity of braiding structure scaffolds not only highly affect cell adhesion and proliferation, but also influence the mechanical behavior of those scaffolds. It is important to develop braiding scaffolds with controllable pore size and distribution. The purpose of this work is to add insight to the mechanics of this passive pore structure control system. Thus, some constitutive equations were established to reveal the relationship between braiding technical parameters (including the number of spindles, braiding structure, cylindrical mandrel radius, and yarn diameter) and the pore size, the porosity of tubular braiding fabric by the mathematical modeling method. Through this model, pore size and the porosity of the tubular braiding scaffold can be precisely controlled by quantitatively adjusting braiding technical parameters. Furthermore, the reliability and accuracy of this model were verified by the experimental data.