Nanosilica-Anchored Polycaprolactone/Chitosan Nanofibrous Bioscaffold to Boost Osteogenesis for Bone Tissue Engineering.

The strategy of incorporating bioactive inorganic nanomaterials without side effects as osteoinductive supplements is promising for bone regeneration. In this work, a novel biomass nanofibrous scaffold synthesized by electrospinning silica (SiO2) nanoparticles into polycaprolactone/chitosan (PCL/CS) nanofibers was reported for bone tissue engineering. The nanosilica-anchored PCL/CS nanofibrous bioscaffold (PCL/CS/SiO2) exhibited an interlinked continuous fibers framework with SiO2 nanoparticles embedded in the fibers. Compact bone-derived cells (CBDCs), the stem cells derived from the bone cortex of the mouse, were seeded to the nanofibrous bioscaffolds. Scanning electron microscopy and cell counting were used to observe the cell adhesion. The Counting Kit-8 (CCK-8) assay was used. Alkaline phosphatase (ALP), Alizarin red staining, real-time Polymerase Chain Reaction and Western blot tests were performed to confirm the osteogenesis of the CBDCs on the bioscaffolds. The research results demonstrated that the mechanical property of the PCL together with the antibacterial and hydrophilic properties of the CS are conducive to promoting cell adhesion, growth, migration, proliferation and differentiation. SiO2 nanoparticles, serving as bone induction factors, effectively promote the osteoblast differentiation and bone regeneration. This novel SiO2-anchored nanofibrous bioscaffold with superior bone induction activity provides a better way for bone tissue regeneration.

Flexible Porous Silicon/Carbon Fiber Anode for High-Performance Lithium-Ion Batteries.

We demonstrate a cross-linked, 3D conductive network structure, porous silicon@carbon nanofiber (P-Si@CNF) anode by magnesium thermal reduction (MR) and the electrospinning methods. The P-Si thermally reduced from silica (SiO2) preserved the monodisperse spheric morphology which can effectively achieve good dispersion in the carbon matrix. The mesoporous structure of P-Si and internal nanopores can effectively relieve the volume expansion to ensure the structure integrity, and its high specific surface area enhances the multi-position electrical contact with the carbon material to improve the conductivity. Additionally, the electrospun CNFs exhibited 3D conductive frameworks that provide pathways for rapid electron/ion diffusion. Through the structural design, key basic scientific problems such as electron/ion transport and the process of lithiation/delithiation can be solved to enhance the cyclic stability. As expected, the P-Si@CNFs showed a high capacity of 907.3 mAh g-1 after 100 cycles at a current density of 100 mA g-1 and excellent cycling performance, with 625.6 mAh g-1 maintained even after 300 cycles. This work develops an alternative approach to solve the key problem of Si nanoparticles' uneven dispersion in a carbon matrix.

The Positive Effect of ZnS in Waste Tire Carbon as Anode for Lithium-Ion Batteries.

There is great demand for high-performance, low-cost electrode materials for anodes of lithium-ion batteries (LIBs). Herein, we report the recovery of carbon materials by treating waste tire rubber via a facile one-step carbonization process. Electrochemical studies revealed that the waste tire carbon anode had a higher reversible capacity than that of commercial graphite and shows the positive effect of ZnS in the waste tire carbon. When used as the anode for LIBs, waste tire carbon shows a high specific capacity of 510.6 mAh·g-1 at 100 mA·g-1 with almost 97% capacity retention after 100 cycles. Even at a high rate of 1 A·g-1, the carbon electrode presents an excellent cyclic capability of 255.1 mAh·g-1 after 3000 cycles. This high-performance carbon material has many potential applications in LIBs and provide an alternative avenue for the recycling of waste tires.

The contribution of Pir protein family to yeast cell surface display.

Proteins with internal repeats (Pir) in the Baker's yeast are located on the cell wall and include four highly homologous members. Recently, Pir proteins have become increasingly used as anchor proteins in yeast cell surface display systems. These display systems are classified into three types: N-terminal fusion, C-terminal fusion, and inserted fusion. In addition to the GPI (glycosylphosphatidyl inositol) and the FL/FS anchor proteins, these three Pir-based systems significantly increase the choices for target proteins to be displayed. Furthermore, Pir proteins can also be used as a fusion partner for target proteins to be effectively secreted into culture medium. Here, we summarize the development and application of Pir proteins as anchor proteins.