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Mn-doped ZnO (MnxZn1−xO) nanoparticles were synthesized by the co-precipitation method and coated with isonipecotic acid as capping ligand. The structure, composition and morphology of the resulting nanomaterial were investigated by energy disperse X-ray analysis, X-ray diffraction, and transmission electron microscopy data. Such measurements showed that the solid obtained contains 6 at% of Mn and it is formed by a highly crystalline material with 3–5 nm range of crystallite size, and only a small elongation of its cell parameter with respect to undoped ZnO wurtzite unit cell. Information on the state of manganese atom in the MnxZn1−xO nanostructures formed was obtained from X-ray photoelectron (XPS) and electron energy loss (EELS) spectroscopies. XPS and EELS spectra are composed of four peaks, corresponding to two species of Mn(II) and signals from Mn(III) and Mn(IV). Such spectral data on the state of Mn in the material studied is consistent with the mapping of Mn distribution observed in recorded transmission electron microscopy images, which reveal presence of clusters of Mn atoms. Only a fraction of doping Mn atoms were found forming a solid solution with the host ZnO structure. The functionalization of the nanoparticles system with Isonipecotic acid shows that this molecule remains anchored to the nanoparticles surface mainly through its N basic site. The availability of free carboxylate groups in the capping molecule was tested by conjugation to type IV horseradish peroxidase.

Cu-doped ZnO (CuxZn1-xO) nanoparticles have been prepared by a co-precipitation method followed by their surface modification with 3-mercaptopropionic acid (MPA). The nature and morphology of the resulting nanostructures were established from X-ray diffraction, transmission electron microscopy and X-ray fluorescence spectroscopy data. Such measurements showed highly crystalline material with nanostructure size of about 3–5 nm and with the indicated chemical composition. Information on the state of copper atom in the CuxZn1-xO structure was obtained from X-ray photoelectron and UV–vis spectroscopies, and magnetic measurements. These techniques together with infrared and photoluminescence spectroscopies were used to study the surface modification of CuxZn1-xO with 3-mercaptopropionic acid. The zinc oxide nanostructures under study display colored light emission. Such fluorescent features and their stability in aqueous media are highly desirable in many potential applications, including biological labels for specific targeting in bioimaging probes and for recognition studies in biosensing applications. The viability of the MPA surface modified CuxZn1-xO nanoparticles to form a surface complex with biomolecules was demonstrated by their conjugation to peroxidase, a molecule with a high versatility for biological assays.

Carlos Lopez-Abarrategui,1 Viviana Figueroa-Espi,2 MariaB Lugo-Alvarez,1 Caroline D Pereira,3 Hilda Garay,4 João ARG Barbosa,5 Rosana Falcão,6 Linnavel Jiménez-Hernández,2 Osvaldo Estévez-Hernández,2,7 Edilso Reguera,8 Octavio L Franco,3,9 SimoniC Dias,3 Anselmo JOtero-Gonzalez1 1Faculty of Biology, Center for Protein Studies, 2Lab of Structural Analysis, Institute of Materials Science and Technology, Havana University, La Habana, Havana, Cuba; 3Center for Biochemical and Proteomics Analyses, Catholic University of Brasilia, Brasilia, Brazil; 4Laboratory of Peptide Analysis and Synthesis, Center of Genetic Engineering and Biotechnology, La Habana, Havana, Cuba; 5Department of Cellular Biology, Laboratory of Biophysics, Institute of Biological Science, University of Brasilia, 6Brazilian Agricultural Research Corporation (EMBRAPA), Center of Genetic Resources and Biotechnology (CENARGEN), Brasilia DF, Brazil; 7Instituto de Ciencia y Tecnología de Materiales (IMRE), Universidad de La Habana, Cuba; 8Research Center for Applied Science and Advanced Technology (CICATA), National Polytechnic Institute (IPN), Lagaria Unit, Mexico DF, Mexico; 9S-Inova Biotech, Post-Graduate in Biotechnology, Universidade Catolica Dom Bosco, Campo Grande, Brazil Abstract: Diseases caused by bacterial and fungal pathogens are among the major health problems in the world. Newer antimicrobial therapies based on novel molecules urgently need to be developed, and this includes the antimicrobial peptides. In spite of the potential of antimicrobial peptides, very few of them were able to be successfully developed into therapeutics. The major problems they present are molecule stability, toxicity in host cells, and production costs. A novel strategy to overcome these obstacles is conjugation to nanomaterial preparations. The antimicrobial activity of different types of nanoparticles has been previously demonstrated. Specifically, magnetic nanoparticles have been widely studied in biomedicine due to their physicochemical properties. The citric acid-modified manganese ferrite nanoparticles used in this study were characterized by high-resolution transmission electron microscopy, which confirmed the formation of nanocrystals of approximately 5 nm diameter. These nanoparticleswere able to inhibit Candida albicans growth in vitro. The minimal inhibitory concentration was 250 µg/mL. However, the nanoparticles were not capable of inhibiting Gram-negative bacteria (Escherichia coli) or Gram-positive bacteria (Staphylococcus aureus). Finally, an antifungal peptide (Cm-p5) from the sea animal Cenchritis muricatus (Gastropoda: Littorinidae) wasconjugated to the modified manganese ferrite nanoparticles. The antifungal activity of the conjugated nanoparticles was higher than their bulk counterparts, showing a minimal inhibitory concentration of 100 µg/mL. This conjugate proved to be nontoxic to a macrophage cell line at concentrations that showed antimicrobial activity. Keywords: nanoparticles, conjugation, antifungal, Cm-p5 peptide

Sapphire is best known for its hardness that makes it ideal for many mechanical and optical applications, but its resistance to radiation damage and its optical properties, combined with metallic nano-particles, make it promising for future opto-electronic and plasmonic devices. In this paper, we present an overview of our work on the fabrication of metallic nano-particles embedded in synthetic sapphire by means of ion implantation, thermal annealing and high energy ion irradiation. We show that we can have control over the amount and size of the nano particles formed inside the matrix by carefully choosing the parameters during the preparation process. Furthermore, we show that anisotropic nano particles can be obtained by an adequate high energy ion irradiation of the originally spherical nano particles. We also have studied the linear and non-linear optical properties of these nano-composites and have confirmed that they are large enough for future applications.

In this paper we report the linear and non-linear optical properties of metallic nano-clusters in α-Al2O3 fabricated by ion implantation (from 2 to 8×1016 ions/cm2). Thereafter, the samples were annealed at temperatures from 600 to 1100 °C in oxidising, reducing atmospheres. Once spherical nano-particles were synthesized, the samples were further irradiated with Si+++ with different energies and fluences to control the achieved anisotropy. As a result of the ion implantation mostly F+ color centers were formed. After thermal annealing they capture an electron to form F centers or combine to form a F2+ center. Also, the photoluminescence signal from Al+ interstitials appears. Regarding the non-linear optical response, the spherical-like Au nano-crystals embedded in sapphire show a positive non-linear absorption at 355 nm and negative non-linear absorption at 532 nm, which shows saturation when increasing the incident irradiance. They also present positive non-linear refraction at 532 nm, which is null at 355 nm. For the anisotropic systems, a larger birefringence than natural values was measured in the visible range by ellipsometry means.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Cystic fibrosis is a disease that conveys a large amount of anxiety. Nevertheless, it is always said that the psychosocial adaptation of the patients and their families is good. In this study, we analyzed the quality of life and the knowledge of the illness possessed by parents of 55 children with cystic fibrosis. The data obtained suggested a good level of knowledge about the disease and an acceptable assessment of their quality of life. The familiar problems reflected in the study concerned regular school attendance and the communication between parents and patients, mainly concerning the illness. This was more obvious with teenagers (12 cases: 21.8%). Finally, it can be stated that the work activity and social relationships of the families had changed notably since the time of diagnosis (70% of the 55 cases reflect this change), with no differences among the age groups. We conclude by stressing the importance of supporting these families, especially at the moment of diagnosis. The associations for cystic fibrosis are of great importance for preventing psychosocial problems amongst their membership.

We see in this study the association between parental mental disorder and the possibility of psychopathology in their children, at the same time pediatric patients. The children of 155 parents suffering of 10 mental disorders have been compared to 267 normal parent's children. The first group has significantly a greater frequency of emotional problems, developmental difficulties, behavioral disorders and a worst academic achievement. The association was more important if to the parental psychopathology was joined a pathological socio-familial milieu.