RESUMO

In this report, we present the results on the physicochemical characterization of cadmium telluride quantum dots (QDs) stabilized with glutathione and prepared by optimizing the synthesis conditions. An excellent control of emissions and the composition of the nanocrystal surface for its potential application in monoclonal antibody and biomarker testing was achieved. Two samples (QDYellow, QDOrange, corresponding to their emission colors) were analyzed by dynamic light scattering (DLS), and their hydrodynamic sizes were 6.7 nm and 19.4 nm, respectively. Optical characterization by UV-vis absorbance spectroscopy showed excitonic peaks at 517 nm and 554 nm. Photoluminescence spectroscopy indicated that the samples have a maximum intensity emission at 570 and 606 nm, respectively, within the visible range from yellow to orange. Infrared spectroscopy showed vibrational modes corresponding to the functional groups OH-C-H, C-N, C=C, C-O, C-OH, and COOH, which allows for the formation of functionalized QDs for the manufacture of biomarkers. In addition, the hydrodynamic radius, zeta potential, and approximate molecular weight were determined by dynamic light scattering (DLS), electrophoretic light scattering (ELS), and static light scattering (SLS) techniques. Size dispersion and the structure of nanoparticles was obtained by Transmission Electron Microscopy (TEM) and by X-ray diffraction. In the same way, we calculated the concentration of Cd2+ ions expressed in mg/L by using the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-OES). In addition to the characterization of the nanoparticles, the labeling of murine myeloid cells was carried out with both samples of quantum dots, where it was demonstrated that quantum dots can diffuse into these cells and connect mostly with the cell nucleus.

RESUMO

A known property of quantum dots (QDs) is their characteristic luminescence, which would make it possible to detect different types of cancers after being functionalized with some type of biological molecule. For this reason, in the present investigation a methodological analysis of the physicochemical characteristics of the CdTe/ZnS core/shell QDs was carried out, using techniques such as Optical Absorbance Spectroscopy (UV-Vis), Molecular Fluorescence, Fourier Transform Infrared Spectroscopy (FT-IR), Dynamic Light Scattering (DLS), X-Ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Zeta Potential that allowed to verify the photoluminescent effectiveness of these semiconductor nanocrystals as an alternative to conventional techniques currently used for the detection of specific cancers smaller than 1 cm. The study consisted of theoretically determining the bandgap energy, the size of the nanocrystals and the molar absorptivity from the wavelength value for the maximum intensity of the excitonic peak. It was also possible to verify the maximum intensity for each sample and thus evaluate its photoluminescent response, as well as it was possible to determine the charge distribution, the hydrodynamic size and the surface composition of each quantum dot. The results obtained correspond to what has been reported in the literature, which makes them good candidates for the detection of cancer in precancerous stages.

RESUMO

Lung cancer educational programs seek the involvement of different groups in efforts to promote healthier habits and lifestyles. Women are primary agents for targeting prevention actions because of their ability to foster healthy lifestyles within their families. The purpose of this study was to develop a woman-centered educational program to strengthen knowledge and promote responsible behavior aimed at primary prevention of lung cancer. Based on identified learning needs in 133 female participants concerning lung cancer self care, healthy habits and communication skills about self care, a ten-workshop series was designed and validated by specialists and users. Before intervention, 82% of participants were highly aware of smoking-related harm, but only 26% were highly aware of healthy environmental management practices at home and 14% were knowledgeable about self care. Differences in both awareness and practice of health-promoting behaviors were observed by the end of the training: those highly aware of smoking-related harm rose to 86.5%, and those highly aware of environmental management and self care increased to 66.2% and 83.5%, respectively. The proportions reporting acceptable levels of environmental management and self-care practices increased to 86.5% (from 0%) and 91% (from 3.8%), respectively. One year later, a positive impact on families was confirmed, predominantly on children. We conclude that such a woman-centered educational program can increase awareness and promote healthy behaviors aimed at lung cancer prevention. Women's ability to communicate and share lessons learned within their families should be considered in designing community health education programs. KEYWORDS Lung cancer, health education, disease prevention, primary prevention, health promotion, Cuba.

Assuntos

Promoção da Saúde/organização & administração , Neoplasias Pulmonares/prevenção & controle , Educação de Pacientes como Assunto , Prevenção Primária , Saúde da Mulher , Adulto , Cuba/epidemiologia , Feminino , Humanos , Neoplasias Pulmonares/epidemiologia , Pessoa de Meia-Idade , Desenvolvimento de Programas

RESUMO

Size-selected TiN nanoclusters in the range of 4 to 20 nm have been produced by an ionized cluster beam, which combines a glow-discharge sputtering with an inert gas condensation technique. With this method, by controlling the experimental conditions, it was possible to produce nanoparticles with a high control in size. The size distribution of TiN nanoparticles was determined before deposition by mass spectroscopy and confirmed by atomic force microscopy. The size distribution was also analyzed using a high-resolution transmission electron micrograph. The photoluminescence [PL] spectra of TiN nanoparticles at different sizes were also experimentally investigated. We reported, for the first time, the strong visible luminescence of TiN nanoparticles on Si (111) wafer due to the reduced size. We also discussed the PL intensity as a function of the nanoparticle size distribution.