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Bioactive ceramics are promising candidates as 3D porous substrates for bone repair in bone regenerative medicine. However, they are often inefficient in clinical applications due to mismatching mechanical properties and compromised biological performances. Herein, the additional Sr dopant is hypothesized to readily adjust the mechanical and biodegradable properties of the dilute Mg-doped wollastonite bioceramic scaffolds with different pore geometries (cylindrical-, cubic-, gyroid-) by ceramic stereolithography. The results indicate that the compressive strength of Mg/Sr co-doped bioceramic scaffolds could be tuned simultaneously by the Sr dopant and pore geometry. The cylindrical-pore scaffolds exhibit strength decay with increasing Sr content, whereas the gyroid-pore scaffolds show increasing strength and Young’s modulus as the Sr concentration is increased from 0 to 5%. The ion release could also be adjusted by pore geometry in Tris buffer, and the high Sr content may trigger a faster scaffold bio-dissolution. These results demonstrate that the mechanical strengths of the bioceramic scaffolds can be controlled from the point at which their porous structures are designed. Moreover, scaffold bio-dissolution can be tuned by pore geometry and doping foreign ions. It is reasonable to consider the nonstoichiometric bioceramic scaffolds are promising for bone regeneration, especially when dealing with pathological bone defects.

In this study, multiscale MWCNT–glass fiber fabric (MGFf) preforms with multiwalled carbon nanotubes (MWCNTs) dispersed onto commercial E-glass fiber fabric (GFf) was used to fabricate the MGFf multiscale composites. The mechanical properties, interlaminar shear strength (ILSS), dynamic viscoelasticity and thermal conductivity of MGFf multiscale composites were investigated using a universal material testing machine, dynamic mechanical thermal analyzer and transient plane source method. Furthermore, the reinforcing mechanisms of MWCNTs on interlaminar adhesion of MGFf multiscale composites were explored using scanning electron and transmission electron microscopy and energy dispersive X-ray spectrometry. Compared with the GFf composite, the ILSS and thermal conductivity of MGFf multiscale composites were increased by 40.5% and 55.3%, respectively; both of the tensile and flexural properties of MGFf multiscale composites were significantly enhanced; the glass transition temperature of MGFf multiscale composites was also raised. In addition, the interface thickness was increased with the addition of MWCNTs, and MWCNTs in MGFf multiscale composites behaved as hooked fibers to improve the interlaminar adhesion. The work demonstrates the great promise of MGFf preforms toward practical industrial application in manufacturing multifunctional fiber composites with high strength and modulus, high shear resistance and good thermal conductivity.

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Dicalcium silicate (C2S) cements doped with Zn or Cu exhibited appreciable osteogenic activity and prolonged antibacterial potential in comparison with C2S cement.

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It is generally accepted that Monascus pigments are predominantly cell-bound, including both intracellular and surface-bound pigments. This long-term misconception was corrected in the present work. Production of extracellular crystal pigments by submerged culture of Monascus sp. was confirmed by microscopic observation and collection of Monascus pigments from extracellular broth by direct membrane filtration. Following up the new fact, the bioactivity of mycelia as whole-cell biocatalyst for biosynthesis and biodegradation of Monascus pigments had been detailedly examined in both an aqueous solution and a nonionic surfactant micelle aqueous solution. Based on those experimental results, cell suspension culture in an aqueous medium was developed as a novel strategy for accumulation of high concentration of Monascus pigments. Thus, glucose feeding during submerged culture in the aqueous medium was carried out successfully and high orange Monascus pigments concentration of near 4 g/L was achieved.