Enhanced Cell Osteogenesis and Osteoimmunology Regulated by Piezoelectric Biomaterials with Controllable Surface Potential and Charges

Bone regeneration is a well-orchestrated process involving electrical, biochemical, and mechanical multiple physiological cues. Electrical signals play a vital role in the process of bone repair. The endogenous potential will spontaneously form on defect sites, guide the cell behaviors, and mediate bone healing when the bone fracture occurs. However, the mechanism on how the surface charges of implant potentially guides osteogenesis and osteoimmunology has not been clearly revealed yet. In this study, piezoelectric BaTiO3/β-TCP (BTCP) ceramics are prepared by two-step sintering, and different surface charges are established by polarization. In addition, the cell osteogenesis and osteoimmunology of BMSCs and RAW264.7 on different surface charges were explored. The results showed that the piezoelectric constant d33 of BTCP was controllable by adjusting the sintering temperature and rate. The polarized BTCP with a negative surface charge (BTCP−) promoted protein adsorption and BMSC extracellular Ca2+ influx. The attachment, spreading, migration, and osteogenic differentiation of BMSCs were enhanced on BTCP–. Additionally, the polarized BTCP ceramics with a positive surface charge (BTCP+) significantly inhibited M1 polarization of macrophages, affecting the expression of the M1 marker in macrophages and changing secretion of proinflammatory cytokines. It in turn enhanced osteogenic differentiation of BMSCs, suggesting that positive surface charges could modulate the bone immunoregulatory properties and shift the immune microenvironment to one that favored osteogenesis. The result provides an alternative method of synergistically modulating cellular immunity and the osteogenesis function and enhancing the bone regeneration by fabricating piezoelectric biomaterials with electrical signals

Fabrication of Mesoporous Co₃O₄ from LP-FDU-12 via Nanocasting Route and Effect of Wall/Pore Size on Their Magnetic Properties

Highly ordered mesoporous Co₃O₄ nanostructures were prepared using LP-FDU-12 as hard templates. By changing the hydrothermal temperature or by the acid treatment of the LP-FDU-12 template, Co₃O₄ replicas with different cell parameters and wall thicknesses have been obtained. The structure and textural characteristics of both LP-FDU-12 and Co₃O₄ replicas were investigated by X-ray diffraction, transmission electron microscopy, and N₂ adsorption–desorption isotherm analysis. The cell parameter and wall thickness of a mesoporous Co₃O₄ have been varied systematically within the ranges 30.4–33.9 and 24.8–18.2 nm, respectively, and the materials exhibit surface areas in the 29.6–52.9 m² g^–1 range, while preserving a highly ordered 3D pore structure and highly crystalline walls. Most importantly, magnetic studies show that the factors which affect the magnetic behavior in the Co₃O₄ nanosphere system are not only the sphere size but also the space-filled parameter at the nanoscale

Very Large, Soluble Endohedral Fullerenes in the Series La₂C₉₀ to La₂C₁₃₈: Isolation and Crystallographic Characterization of La₂@<i>D</i>₅(450)-C₁₀₀

An extensive series of soluble dilanthanum endohedral fullerenes that extends from La2C90 to La2C138 has been discovered. The most abundant of these, the nanotubular La2@D5(450)-C100, has been isolated in pure form and characterized by single-crystal X-ray diffraction

Very Large, Soluble Endohedral Fullerenes in the Series La₂C₉₀ to La₂C₁₃₈: Isolation and Crystallographic Characterization of La₂@<i>D</i>₅(450)-C₁₀₀

An extensive series of soluble dilanthanum endohedral fullerenes that extends from La2C90 to La2C138 has been discovered. The most abundant of these, the nanotubular La2@D5(450)-C100, has been isolated in pure form and characterized by single-crystal X-ray diffraction

X‑ray Crystallographic Characterization of New Soluble Endohedral Fullerenes Utilizing the Popular C₈₂ Bucky Cage. Isolation and Structural Characterization of Sm@<i>C</i>_3<i>v</i>(7)‑C₈₂, Sm@<i>C</i>_<i>s</i>(6)‑C₈₂, and Sm@<i>C</i>₂(5)‑C₈₂

Three isomers of Sm@C₈₂ that are soluble in organic solvents were obtained from the carbon soot produced by vaporization of hollow carbon rods doped with Sm₂O₃/graphite powder in an electric arc. These isomers were numbered as Sm@C₈₂(I), Sm@C₈₂(II), and Sm@C₈₂(III) in order of their elution times from HPLC chromatography on a Buckyprep column with toluene as the eluent. The identities of isomers, Sm@C₈₂(I) as Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@C₈₂(II) as Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@C₈₂(III) as Sm@<i>C</i>₂(5)-C₈₂, were determined by single-crystal X-ray diffraction on cocrystals formed with Ni­(octaethylporphyrin). For endohedral fullerenes like La@C₈₂, which have three electrons transferred to the cage to produce the M³⁺@(C₈₂)^3– electronic distribution, generally only two soluble isomers (<i>e.g.</i>, La<i>@C</i>_2<i>v</i>(9)-C₈₂ (major) and La@<i>C</i>_<i>s</i>(6)-C₈₂ (minor)) are observed. In contrast, with samarium, which generates the M²⁺@(C₈₂)^2– electronic distribution, five soluble isomers of Sm@C₈₂ have been detected, three in this study, the other two in two related prior studies. The structures of the four Sm@C₈₂ isomers that are currently established are Sm@<i>C</i>₂(5)-C₈₂, Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@<i>C</i>_2<i>v</i>(9)-C₈₂. All of these isomers obey the isolated pentagon rule (IPR) and are sequentially interconvertable through Stone–Wales transformations

X‑ray Crystallographic Characterization of New Soluble Endohedral Fullerenes Utilizing the Popular C₈₂ Bucky Cage. Isolation and Structural Characterization of Sm@<i>C</i>_3<i>v</i>(7)‑C₈₂, Sm@<i>C</i>_<i>s</i>(6)‑C₈₂, and Sm@<i>C</i>₂(5)‑C₈₂

Three isomers of Sm@C₈₂ that are soluble in organic solvents were obtained from the carbon soot produced by vaporization of hollow carbon rods doped with Sm₂O₃/graphite powder in an electric arc. These isomers were numbered as Sm@C₈₂(I), Sm@C₈₂(II), and Sm@C₈₂(III) in order of their elution times from HPLC chromatography on a Buckyprep column with toluene as the eluent. The identities of isomers, Sm@C₈₂(I) as Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@C₈₂(II) as Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@C₈₂(III) as Sm@<i>C</i>₂(5)-C₈₂, were determined by single-crystal X-ray diffraction on cocrystals formed with Ni­(octaethylporphyrin). For endohedral fullerenes like La@C₈₂, which have three electrons transferred to the cage to produce the M³⁺@(C₈₂)^3– electronic distribution, generally only two soluble isomers (<i>e.g.</i>, La<i>@C</i>_2<i>v</i>(9)-C₈₂ (major) and La@<i>C</i>_<i>s</i>(6)-C₈₂ (minor)) are observed. In contrast, with samarium, which generates the M²⁺@(C₈₂)^2– electronic distribution, five soluble isomers of Sm@C₈₂ have been detected, three in this study, the other two in two related prior studies. The structures of the four Sm@C₈₂ isomers that are currently established are Sm@<i>C</i>₂(5)-C₈₂, Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@<i>C</i>_2<i>v</i>(9)-C₈₂. All of these isomers obey the isolated pentagon rule (IPR) and are sequentially interconvertable through Stone–Wales transformations

X‑ray Crystallographic Characterization of New Soluble Endohedral Fullerenes Utilizing the Popular C₈₂ Bucky Cage. Isolation and Structural Characterization of Sm@<i>C</i>_3<i>v</i>(7)‑C₈₂, Sm@<i>C</i>_<i>s</i>(6)‑C₈₂, and Sm@<i>C</i>₂(5)‑C₈₂

Three isomers of Sm@C₈₂ that are soluble in organic solvents were obtained from the carbon soot produced by vaporization of hollow carbon rods doped with Sm₂O₃/graphite powder in an electric arc. These isomers were numbered as Sm@C₈₂(I), Sm@C₈₂(II), and Sm@C₈₂(III) in order of their elution times from HPLC chromatography on a Buckyprep column with toluene as the eluent. The identities of isomers, Sm@C₈₂(I) as Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@C₈₂(II) as Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@C₈₂(III) as Sm@<i>C</i>₂(5)-C₈₂, were determined by single-crystal X-ray diffraction on cocrystals formed with Ni­(octaethylporphyrin). For endohedral fullerenes like La@C₈₂, which have three electrons transferred to the cage to produce the M³⁺@(C₈₂)^3– electronic distribution, generally only two soluble isomers (<i>e.g.</i>, La<i>@C</i>_2<i>v</i>(9)-C₈₂ (major) and La@<i>C</i>_<i>s</i>(6)-C₈₂ (minor)) are observed. In contrast, with samarium, which generates the M²⁺@(C₈₂)^2– electronic distribution, five soluble isomers of Sm@C₈₂ have been detected, three in this study, the other two in two related prior studies. The structures of the four Sm@C₈₂ isomers that are currently established are Sm@<i>C</i>₂(5)-C₈₂, Sm@<i>C</i>_<i>s</i>(6)-C₈₂, Sm@<i>C</i>_3<i>v</i>(7)-C₈₂, and Sm@<i>C</i>_2<i>v</i>(9)-C₈₂. All of these isomers obey the isolated pentagon rule (IPR) and are sequentially interconvertable through Stone–Wales transformations