It is of great importance to develop multifunctional bioactive scaffolds, which combine angiogenesis capacity, osteostimulation, and antibacterial properties for regenerating lost bone tissues. In order to achieve this aim, we prepared copper (Cu)-containing mesoporous bioactive glass (Cu-MBG) scaffolds with interconnective large pores (several hundred micrometer) and well-ordered mesopore channels (around 5 nm). Both Cu-MBG scaffolds and their ionic extracts could stimulate hypoxia-inducible factor (HIF)-1a and vascular endothelial growth factor(VEGF) expression in human bone marrow stromal cells(hBMSCs). In addition, both Cu-MBG scaffolds and their ionic extracts significantly promoted the osteogenic differentiation of hBMSCs by improving their bone-related gene expression (alkaline phosphatase (ALP), osteopontin(OPN) and osteocalcin (OCN)). Furthermore, Cu-MBG scaffolds could maintain a sustained release of ibuprofen and significantly inhibited the viability of bacteria. This study indicates that the incorporation of Cu2þ ions into MBG scaffolds significantly enhances hypoxia-like tissue reaction leading to the coupling of angiogenesis and osteogenesis. Cu2þ ions play an important role to offer the multifunctional properties of MBG scaffold system. This study has demonstrated that it is possible to develop multifunctional scaffolds by combining enhanced angiogenesis potential, osteostimulation, and antibacterial properties for the treatment of large bone defects.

Copper-containing mesoporous bioactive glass scaffolds with multifunctional properties of angiogenesis capacity, osteostimulation and antibacterial activity

Single-atom photocatalysts have shown their compelling potential and arguably become the most active research direction in photocatalysis due to their fascinating strengths in enhancing light-harvesting, charge transfer dynamics, and surface reactions of a photocatalytic system. While numerous comprehensions about the single-atom photocatalysts have recently been amassed, advanced characterization techniques and vital theoretical studies are strengthening our understanding on these fascinating materials, allowing us to forecast their working mechanisms and applications in photocatalysis. In this review, we begin by describing the general background and definition of the single-atom photocatalysts. A brief discussion of the metal-support interactions on the single-atom photocatalysts is then provided. Thereafter, the current available characterization techniques for single-atom photocatalysts are summarized. After having some fundamental understanding on the single-atom photocatalysts, their advantages and applications in photocatalysis are discussed. Finally, we end this review with a look into the remaining challenges and future perspectives of single-atom photocatalysts. We anticipate that this review will provide some inspiration for the future discovery of the single-atom photocatalysts, manifestly stimulating the development in this emerging research area.

Heterogeneous Single-Atom Photocatalysts: Fundamentals and Applications.

Acid mine drainage: Prevention, treatment options, and resource recovery: A review

Among the most challenging problems that human beings appear to face are depleting energy sources and increasing environmental pollutions. Heterogeneous photocatalytic processes are the most reward...

Magnetically separable nanocomposites based on ZnO and their applications in photocatalytic processes: A review

V.F.C. and A.F. contributed equally to this work. The authors thank the FCT—Fundacao para a Ciencia e Tecnologia—for financial support under framework of the Strategic Funding UID/FIS/04650/2013, project PTDC/ EEI-SII/5582/2014 and project UID/EEA/04436/2013 by FEDER funds through the COMPETE 2020—Programa Operacional Competitividade e Internacionalizacao (POCI). Funds provided by FCT in the framework of EuroNanoMed 2016 call, Project LungChek ENMed/0049/2016 are also gratefully acknowledged. V.F.C., A.F., C.R., and P.M. also thank the FCT for the grants SFRH/BPD/98109/2013, SFRH/BPD/104204/2014, SFRH/ BPD/90870/2012 and SFRH/BPD/96227/2013, respectively. Finally, the authors acknowledge funding by the Spanish Ministry of Economy and Competitiveness (MINECO) through the project MAT2016-76039C4-3-R (AEI/FEDER, UE) and from the Basque Government Industry Department under the ELKARTEK program.

Advances in Magnetic Nanoparticles for Biomedical Applications.

In this study, the preparation of hydroxyapatite–copper (HA-Cu) nanocomposite coatings is based on electrophoretic deposition (EPD) method and their bioactivity, antibacterial behavior, and cytotoxicity are assessed. The HA-Cu nanocomposite coatings with different amounts of Cu (1, 3 and 5 wt%) deposited on Ti6Al4V substrates. The surface morphology, composition, and microstructure of these coatings are characterized through scanning electron microscopy (SEM) equipped with energy dispersive spectrometer (EDS), and X-ray diffraction (XRD). Adding Cu nanoparticles into HA increased particle size and made coatings porous due to agglomeration of nano-sized particles. The in vitro bioactivity of these coatings is assessed by SEM and inductively coupled plasma (ICP) in simulated body fluid (SBF) for 28 days. The results indicate that an increase of Cu to nanocomposite coating, decreases the bioactivity, while adhesive strength of nanocomposite is increased. Antibacterial tests of as-prepared HA-Cu nanocomposites and pure-HA are assessed against E. coli and S. aureus and results indicate that pure-HA did not exhibit any antibacterial activity, whereas the presence of Cu in HA resulted in a good activity against E. coli and S. aureus. In vitro biocompatibility tests, MTT, are run to assess the cytotoxicity of HA-Cu nanocomposite coatings with osteoblast-like MG63 cells. The obtained HA-Cu nanocomposite coatings except for the sample with 5 wt% Cu exhibited higher cytocompatibility compared to pure-HA up to 7 days. It is revealed here that HA-3 wt% Cu nanocomposite coated on Ti-6Al-4V substrate with more efficient antibacterial properties (HA-3 wt% Cu vs. HA-1 wt% Cu) and better cytocompatibility (HA-3 wt% Cu vs. HA-5 wt% Cu) compared to other specimens, has higher potential to be applied as a promising bone implant with antibacterial capability in the bone tissue engineering.

Electrophoretic-deposited hydroxyapatite-copper nanocomposite as an antibacterial coating for biomedical applications

https://wiki.epfl.ch/mazaheri/documents/Publication/Conference/7.pdf

S.A. Hassanzadeh-Tabrizi

Papers

Electrophoretic-deposited hydroxyapatite-copper nanocomposite as an antibacterial coating for biomedical applications

Reverse precipitation synthesis and characterization of CeO2 nanopowder

In situ microemulsion synthesis of hydroxyapatite-MgFe2O4 nanocomposite as a magnetic drug delivery system.

Synthesis of ZnO/CuO nanocomposite immobilized on γ-Al 2 O 3 and application for removal of methyl orange

Failure analysis of drill pipe: A review