3D sub-cellular localization of upconverting nanoparticles through hyperspectral microscopy

Hyperspectral microscopy is an intriguing technique combining spectroscopy with optical microscopy that can be used to simultaneously obtain spectral and spatial information. The relevance of hyperspectral imaging in biomedical applications such as the monitoring of bioimaging agents, the identification of pathogens and cancerous cells, and the cellular uptake of nanoparticles has emerged recently, due to recent advances in optical reconstruction. The location and tracking of particles within the cell structure have been analyzed by 2D hyperspectral imaging of non-fluorescence objects, being examples of 3D localization uncommon. Here, we report the synthesis of Yb3+/Er3+-codoped Gd2O3 nanoparticles, their structural and luminescence characterization, and their biocompatibility assessments in Human melanoma (MNT-1 and A375) cell lines. The internalization of the particles by MNT-1 cells and their 3D localization in a fixed configuration are addressed through 2D optical images acquired in different planes along with the cell culture depth. 2D hyperspectral imaging is used to unequivocally identify the nuclei and the nanoparticles. The results indicate that the particles are distributed in distinct planes deep in the cell volume in the cytoplasmic and perinuclear regions. Furthermore, the emission signature of the nanoparticles enabled the determination of the intracellular temperaturepublishe

Au sujet de la lecture et l’écriture au Chili

Los indicadores sobre lectura en Chile dan cuenta de que los chilenos no leen o están leyendo mal. Sin embargo, las políticas públicas privilegian el adiestramiento de los niños en el uso de las tecnologías de la información y la comunicación (TIC). A esta concepción, bajo la que subyace la idea de la obsolescencia del libro, el autor sostiene que la lectura de libros pone en actividad dimensiones de lo humano que son esenciales. Leer libros, afirma, tiene virtudes propias que nuestro trato con las TIC no tiene. Les indicateurs sur la lecture au Chili mettent de l’avant le fait que les Chiliens ne lisent pas ou lisent mal. Cependant, les politiques publiques visent de manière prioritaire la formation des enfants à l'utilisation des technologies de l'information et de la communication (TIC). Dans cette conception, sous laquelle se trouve la notion d'obsolescence du livre, l'auteur affirme que la lecture de livres en activité des dimensions humaines qui sont essentielles. Le fait de lire des libres a des vertus qui lui sont propres et très différentes de nos liens avec les TIC.&nbsp

Joining Time-Resolved Thermometry and Magnetic-Induced Heating in a Single Nanoparticle Unveils Intriguing Thermal Properties

Whereas efficient and sensitive nanoheaters and nanothermometers are demanding tools, in modern bio- and nanomedicine, joining both features in a single nanoparticle still remains a real challenge, despite the recent progress achieved, Most Of it Within the last year. Here we demonstrate a successful realization of this challenge. The heating is magnetically induced, the temperature readout is optical, and the ratiometric thermometric probes are dual-emissive Eu3+/Tb3+ lanthanide complexes. The low thermometer heat capacitance (0.021 center dot K-1) and heater/thermometer resistance (1 K center dot W-1), the high temperature sensitivity (5.8%center dot K-1 at 296 K) and uncertainty (0.5 K), the physiological working temperature range (295-315 K), the readout reproducibility (>99.5%), and the fast time response (0.250 s) make the heater/thermometer nanoplatform proposed here unique. Cells were incubated with the nanoparticles, and fluorescence microscopy permits the mapping of the intracellular local temperature using the pixel-by-pixel ratio of the Eu3+/Tb3+ intensities. Time-resolved thermometry under an ac magnetic field evidences the failure of using Macroscopic thermal parameters to describe heat diffusion at the nanoscale