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The paper reports for the first time an innovative polyaniline (PANI)/platinum (Pt)-coated fiber optic-surface plasmon resonance (FO-SPR) sensor used for highly-sensitive 4-nitrophenol (4-NP) pollutant detection. The Pt thin film was coated over an unclad core of an optical fiber (FO) using a DC magnetron sputtering technique, while the 4-NP responsive PANI layer was synthetized using a cost-effective electroless polymerization method. The presence of the electrolessly-grown PANI on the Pt-coated FO was observed by field-emission scanning electron microscopy and subsequently evidenced by energy dispersive X-ray analysis. These FO-SPR sensors with a demonstrated bulk sensitivity of 1515 nm/RIU were then employed for 4-NP sensing, exhibiting an excellent limit-of-detection (LOD) in the low picomolar range (0.34 pM). The proposed sensor's configuration has many other advantages, such as low-cost production, small size, immunity to electromagnetic interferences, remote sensing capability, and moreover, can be operated as a "stand-alone device", making it thus well-suited for applications such as "on-site" screening of extremely low-level trace pollutants. [ABSTRACT FROM AUTHOR]

A composite material with applications in optoelectronics has been investigated. Pulsed laser deposition CdSe-doped glass film was prepared by the combinatorial deposition from two targets, namely pure CdSe and glass belonging to the 20Li2O-10Al2O3-7BaO-2La2O3-2ZnO-59P2O5 system. Exciton peaks in the Vis domain, related to electron–hole pairs transitions from the valence band to the conduction band, were revealed in the optical absorption spectra of the CdSe-doped film. CdSe quantum dots (QDs) band gap energy depends on the CdSe quantum confinement effect. CdSe-doped film photoluminescence exhibits peaks in the red domain assigned to CdSe transitions from the excited state to the ground state. The size of CdSe nanoclusters, determined from x-ray diffraction is correlated with scanning electron microscopy–energy dispersive x-ray spectroscopy and atomic force microscopy results. Vibration modes specific both to CdSe QDs and to the vitreous network have been evidenced by Fourier transform infrared and Raman spectroscopy. [ABSTRACT FROM AUTHOR]

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 (FeO@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. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

This paper reports a new bioactive surface based on magnetic microspheres with an average size up to 500 nm. Magnetic microspheres consisting of 8 nm magnetite nanoparticles functionalized with Melissa officinalis essential oil, poly lactic acid and chitosan were prepared using a solvent evaporation method and pelliculized by MAPLE. The as prepared surface was characterized by X-ray diffraction, infrared and scanning electron microscopy. The in vitro experiments revealed a good compatibility with eukaryotic cells a significant inhibitory activity of the prokaryotic cells adherence properties. This approach could be a successful method to control and prevent microbial biofilms associated infections and may be also used as an alternative strategy to limit the consumption of synthetic antimicrobial drugs in order to decrease the rates of microbial resistance to antibiotics. Graphical abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Poly(lactic-co-glycolic) acid/chitosan microsphere coatings containing Cinnamomi aetheroleum-functionalized magnetite nanoparticles (FeO@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. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Papain thin films were synthesised by matrix assisted and conventional pulsed laser deposition (PLD) techniques. The targets submitted to laser radiation consisted on a frozen composite obtained by dissolving the biomaterials in distilled water. For the deposition of the thin films by conventional PLD pressed biomaterial powder targets were submitted to laser irradiation. An UV KrF* excimer laser source was used in the experiments at 0.5 J/cm2 incident fluence value, diminished one order of magnitude as compared to irradiation of inorganic materials. The surface morphology of the obtained thin films was studied by atomic force profilometry and atomic force microscopy. The investigations showed that the growth mode and surface quality of the deposited biomaterial thin films is strongly influenced by the target preparation procedure. [ABSTRACT FROM AUTHOR]

Due to their excellent mechanical and biocompatibility properties, titanium-based implants are successfully used as biomedical devices. However, when new bone formation fails for different reasons, impaired fracture healing becomes a clinical problem and affects the patient's quality of life. We aimed to design a new bioactive surface of titanium implants with a synergetic PEG biopolymer-based composition for gradual delivery of growth factors (FGF2, VEGF, and BMP4) during bone healing. The optimal architecture of non-cytotoxic polymeric coatings deposited by dip coating under controlled parameters was assessed both in cultured cells and in a rat tibial defect model (100% viability). Notably, the titanium adsorbed polymer matrix induced an improved healing process when compared with the individual action of each biomolecules. High-performance mass spectrometry analysis demonstrated that recovery after a traumatic event is governed by specific differentially regulated proteins, acting in a coordinated response to the external stimulus. Predicted protein interactions shown by STRING analysis were well organized in hub-based networks related with response to chemical, wound healing and response to stress pathways. The proposed functional polymer coatings of the titanium implants demonstrated the significant improvement of bone healing process after injury. [ABSTRACT FROM AUTHOR]