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Zanfir A.V.,Polytechnic University of Bucharest | Voicu G.,Polytechnic University of Bucharest | Busuioc C.,Polytechnic University of Bucharest | Jinga S.I.,Polytechnic University of Bucharest | And 2 more authors.
Materials Science and Engineering C | Year: 2016

The integration of ceramic powders in composite materials for bone scaffolds can improve the osseointegration process. This work was aimed to the synthesis and characterization of new collagen-hydroxyapatite/barium titanate (Coll-HA/BT) composite materials starting from barium titanate (BT) nanopowder, hydroxyapatite (HA) nanopowder and collagen (Coll) gel. BT nanopowder was produced by combining two wet-chemical approaches, sol-gel and hydrothermal methods. The resulting materials were characterized in terms of phase composition and microstructure by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. Moreover, the biocompatibility and bioactivity of the composite materials were assessed by in vitro tests. The synthesized BT particles exhibit an average size of around 35 nm and a spherical morphology, with a pseudo-cubic or tetragonal symmetry. The diffraction spectra of Coll-HA and Coll-HA/BT composite materials indicate a pronounced interaction between Col and the mineral phases, meaning a good mineralization of Col fibres. As well, the in vitro tests highlight excellent osteoinductive properties for all biological samples, especially for Coll-HA/BT composite materials, fact that can be attributed to the ferromagnetic properties of BT. © 2016 Elsevier B.V. All rights reserved. Source


Holban A.M.,Polytechnic University of Bucharest | Holban A.M.,University of Bucharest | Andronescu E.,Polytechnic University of Bucharest | Grumezescu V.,Polytechnic University of Bucharest | And 7 more authors.
Journal of Sol-Gel Science and Technology | Year: 2015

In this study, we aimed to improve and extend the microbiological applications of magnetic nanocarriers, by the successful fabrication of a new nanostructured surface based on 7 nm average diameter magnetite and carvone (Fe3O4@CAR) nanoparticles and to evaluate the biological activity of this material deposed as a thin film by advanced laser techniques (MAPLE). The results demonstrate that the thin surfaces containing the fabricated bio-active nanosystem have a great antimicrobial activity, inhibiting the colonization and biofilm formation of both Gram positive and Gram negative tested species. Furthermore, the in vitro results demonstrate that this material is not cytotoxic, allowing the normal growth and development of human endothelial cells. Our results demonstrate that the fabricated magnetic bioactive nanostructured surfaces have a great potential to be used for the development of novel applications on the medical field, particularly in the control of infectious diseases. © 2014, Springer Science+Business Media New York. Source


Grumezescu V.,Polytechnic University of Bucharest | Grumezescu V.,Romanian National Institute for Lasers, Plasma and Radiation Physics | Andronescu E.,Romanian National Institute for Lasers, Plasma and Radiation Physics | Holban A.M.,Polytechnic University of Bucharest | And 8 more authors.
Applied Surface Science | Year: 2015

The purpose of this study was the fabrication of functionalized anti-adherent surfaces based on the polyvinyl chloride (PVC) coated with 3-amino propyltrimethoxysilane (APTMS) by matrix assisted pulsed laser evaporation (MAPLE) in order to improve the resistance of PVC based prosthetic devices to microbial colonization. Infrared microscopy (IRM) investigations of APTMS thin films proved the compositional homogeneity of the prepared thin film. Scanning electron microscopy (SEM) micrographs revealed a granular morphology with microspheres harboring a diameter between 15 and 60 nm. The microbiological assays proved that MAPLE deposited APTMS films inhibited the adherence capacity and biofilm development of Pseudomonas aeruginosa and Staphylococcus aureus strains. Furthermore, this material proved to be highly biocompatible, allowing the normal growth and development of human endothelial cells. These traits highlight the fact that the fabricated APTMS thin films may be efficiently used for improving different surfaces of medical use, including prostheses and implantable devices. © 2015 Elsevier B.V. All rights reserved. Source


Iordache F.,Institute of Cellular Biology and Pathology of Romanian Academy | Oprea A.E.,Polytechnic University of Bucharest | Grumezescu V.,Polytechnic University of Bucharest | Grumezescu V.,Romanian National Institute for Lasers, Plasma and Radiation Physics | And 8 more authors.
Journal of Sol-Gel Science and Technology | Year: 2015

Abstract: Poly(lactic-co-glycolic) acid/chitosan microsphere coatings containing Cinnamomi aetheroleum-functionalized magnetite nanoparticles (Fe3O4@CA) were deposited by matrix-assisted pulsed laser evaporation in order to improve the surface resistance to microbial colonization. The obtained surface proved a very good biocompatibility and demonstrates that bacterial colonization is impaired on the nanomodified bioactive surfaces and also Staphylococcus aureus biofilm formation is significantly altered. © 2015, Springer Science+Business Media New York. Source


Grumezescu V.,Romanian National Institute for Lasers, Plasma and Radiation Physics | Grumezescu V.,Polytechnic University of Bucharest | Holban A.M.,University of Bucharest | Iordache F.,Institute of Cellular Biology and Pathology of Romanian Academy | And 8 more authors.
Applied Surface Science | Year: 2014

This study reports the biological applications of a newly fabricated water dispersible nanostructure, based on magnetite (Fe3O4) and eugenol (E), prepared in a well-shaped spherical form by precipitation method. The presence of Fe3O4@E nanoparticles has been confirmed by transmission electron microscopy (TEM). Nanoparticles have been embedded into poly(3-hidroxybutyric acid-co-3-hidroxyvaleric acid)-polyvinyl alcohol (P(3HB-3HV)-PVA) microspheres by oil-in-water emulsion technique. Functionalized P(3HB-3HV)-PVA-Fe3O4@E microspheres coatings have been fabricated by matrix assisted pulsed laser evaporation (MAPLE). The coatings have been characterized by infrared microscopy (IRM) and scanning electron microscopy (SEM). In vitro biofilm formation by Staphylococcus aureus and Pseudomonas aeruginosa was assessed by the viable cell counts technique. Nanomaterial biocompatibility has been investigated by analyzing the phenotypic changes of cultured eukaryotic cells. Besides their excellent anti-adherence and anti-biofilm properties, the MAPLE coatings have the advantages of using bioactive natural compounds, which are less toxic and easily biodegradable than current antibiotics. This approach could be used as a successful alternative or adjuvant method to control and prevent microbial biofilms associated infections. © 2014 Elsevier B.V. All rights reserved. Source

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