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Various surface bioactivation technology has been confirmed to improve the osteogenic ability of porous titanium (pTi) implants effectively. In this study, a three-layered composite coating, i.e. outer layer of hydroxyapatite (HA), middle layer of loose titanium dioxide (L-TiO2) and inner layer of dense TiO2 (D-TiO2), was fabricated on pTi by a combined processing procedure of pickling, alkali heat (AH), anodic oxidation (AO), electrochemical deposition (ED) and hydrothermal treatment (HT). After soaking in simulated body fluid for 48 h, the surface of the AHAOEDHT-treated pTi was completely covered by a homogeneous apatite layer. Using MC3T3-E1 pro-osteoblasts as cell model, the cell culture revealed that both the pTi without surface treatment and the AHAOEDHT sample could support the attachment, growth and proliferation of the cells. Compared to the pTi sample, the AHAOEDHT one induced higher expressions of osteogenesis-related genes in the cells, including alkaline phosphatase, Type I collagen, osteopontin, osteoclast inhibitor, osteocalcin and zinc finger structure transcription factor. As thus, besides the good corrosion resistance, the HA/L-TiO2/D-TiO2-coated pTi had good osteogenic activity, showing good potential in practical application for bone defect repair. [ABSTRACT FROM AUTHOR]

Scanning tunneling microscopy and spectroscopy (STM/STS) experiments on a high-density sintered MgB2 surface were performed at 4.2 K, using a low-temperature STM. For a 20-min Ar+ ion sputtered MgB2 surface, a double-gap structure with gap values of ΔL=9.5 meV and ΔS=4.0 meV was clearly observed in the local tunneling spectra, exhibiting the BCS-shaped characteristic with a metallic background. But for a 2-h Ar+ ion sputtered surface, the observed current–voltage characteristics of the MgB2 surface show metallic electronic transport behavior. In an attempt to clarify the effect of Ar+ ion sputtering on the electronic transport, the MgB2 surface was characterized by Auger electron spectroscopy (AES). The compositional changes of the MgB2 surface were investigated in real time during the course of Ar+ ion sputtering. The detailed compositional analysis of the MgB2 surface may help to elucidate the various electronic transport behavior observed in surface-sensitive STS measurements. [Copyright &y& Elsevier]

The past decades have witnessed the rational design of novel functional nanomaterials and the potential to revolutionize many applications. With the increasing focus on electronic biological processes, novel photovoltaic nanomaterials are highly expectable for empowering new therapeutic strategies such as establishing a link between endogenous electric field (EEF) and electrotherapy. Compared to traditional invasive stimulation, the light-initiating strategy has the advantages of non-invasion, non-power supply, and precise controllability. Whereas, common photoactivated materials require short-wavelength light excitation accompanied by poor tissue penetration and biohazard. Herein, by the construction of p-n heterostructured Bi 2 S 3 /TiO 2 /rGO (BTG) nanoparticles, broadener light absorption and higher light conversion than regular UV excitation are realized. Simultaneously, the photoelectric performance of BTG heterostructure, as well as the synergistic effect of Bi 2 S 3 morphology, are revealed. Besides, the rationally designed biomimetic hydrogel matrix consisting of collagen and hyaluronic acid provides appropriate bioactivity, interface adhesion, mechanical matching, and electron transfer. Therefore, the photovoltaic BTG-loaded matrix provides a platform of light-driven electrical stimulation, coupling the EEF to modulate the electrophysiological and regeneration microenvironment. The implementation of photoelectric stimulation holds broad prospects for non-drug therapy and electrical-related biological process modulation including osseointegration, nerve regeneration, electronic skin, and wound healing., (© 2022 Wiley-VCH GmbH.)

Various surface bioactivation technology has been confirmed to improve the osteogenic ability of porous titanium (pTi) implants effectively. In this study, a three-layered composite coating, i.e. outer layer of hydroxyapatite (HA), middle layer of loose titanium dioxide (L-TiO 2 ) and inner layer of dense TiO 2 (D-TiO 2 ), was fabricated on pTi by a combined processing procedure of pickling, alkali heat (AH), anodic oxidation (AO), electrochemical deposition (ED) and hydrothermal treatment (HT). After soaking in simulated body fluid for 48 h, the surface of the AHAOEDHT-treated pTi was completely covered by a homogeneous apatite layer. Using MC3T3-E1 pro-osteoblasts as cell model, the cell culture revealed that both the pTi without surface treatment and the AHAOEDHT sample could support the attachment, growth and proliferation of the cells. Compared to the pTi sample, the AHAOEDHT one induced higher expressions of osteogenesis-related genes in the cells, including alkaline phosphatase, Type I collagen, osteopontin, osteoclast inhibitor, osteocalcin and zinc finger structure transcription factor. As thus, besides the good corrosion resistance, the HA/L-TiO 2 /D-TiO 2 -coated pTi had good osteogenic activity, showing good potential in practical application for bone defect repair., (© The Author(s) 2020. Published by Oxford University Press.)

We focus our studies on DNA-chromophore motif on surfaces using samples prepared by the synthetic methods described by Wang and Li in a recent publication (J. Am. Chem. Soc. 2003, 125, 5248-5249). Scanning tunneling microscope (STM) was used to investigate the DNA-chromophore hybrids adsorbed on Au(111) and highly oriented pyrolytic graphite (HOPG) surfaces at room temperature in air. Experiments found that the DNA-chromophore hybrid molecules easily formed multimolecule aggregations on gold surface. On HOPG surfaces, however, DNA-chromophore hybrids were usually adsorbed as single molecules. STM images further showed DNA-chromophore hybrids adsorbed on Au(111) surfaces existed in the form of single molecule, dimer, trimer, tetramer, etc. The occurrence of molecular aggregations indicates that molecular interactions are comparable or stronger than molecule-substrate interactions; such weak interactions control the geometrical sizes and topographical shapes of the self-assembled DNA-chromophore hybrids on surfaces.