Novel (bio)chemical and (photo)physical probes for imaging live cells

Emerging technologies, utilizing a combination of chemistry, physics and molecular biology, are creating an increasing interest in smart materials serving as reporters and sensors in micro- and nano-systems. Such devices constitute unique tools for a plethora of biological applications and therapies, allowing in vivo and real time monitoring of biomolecular structure and function. Imaging live cells poses a number of problems, not the least of which is to minimize the perturbation of the physiological state and viability of the cells with the probes and "tools". One seeks to achieve single molecule sensitivity (when appropriate and desirable), monitor fast kinetic processes, and observe molecular interactions occurring on distance scales far beyond the optical resolution of light microscopes. In the remainder of this contribution we discuss a few methods that have already attained some of these goals and present some model systems that hold the promise for achieving others. (excerpt from Section 2, this article contains no abstract

Novel (bio)chemical and (photo)physical probes for imaging live cells

Emerging technologies, utilizing a combination of chemistry, physics and molecular biology, are creating an increasing interest in smart materials serving as reporters and sensors in micro- and nano-systems. Such devices constitute unique tools for a plethora of biological applications and therapies, allowing in vivo and real time monitoring of biomolecular structure and function. Imaging live cells poses a number of problems, not the least of which is to minimize the perturbation of the physiological state and viability of the cells with the probes and "tools". One seeks to achieve single molecule sensitivity (when appropriate and desirable), monitor fast kinetic processes, and observe molecular interactions occurring on distance scales far beyond the optical resolution of light microscopes. In the remainder of this contribution we discuss a few methods that have already attained some of these goals and present some model systems that hold the promise for achieving others. (excerpt from Section 2, this article contains no abstract

Photoswitchable water-soluble quantum dots: PcFRET based on amphiphilic photochromic polymer coating

A novel surface architecture was developed to generate biocompatible and stable photoswitchable quantum dots (psQDs). Photochromic diheteroarylethenes, which undergo thermally stable photoconversions between two forms with different spectral properties in organic solvents, were covalently linked to an amphiphilic polymer that self-assembles with the lipophilic chains surrounding commercial hydrophobic core-shell CdSe/ZnS QDs. This strategy creates a small (∼7 nm diameter) nanoparticle (NP) that is soluble in aqueous medium. The NP retains and even enhances the desirable properties of the original QD (broad excitation, narrow emission, photostability), but the brightness of its emission can be tailored by light. The modulation of emission monitored by steady-state and time-resolved fluorescence was 35-40%. The psQDs exhibit unprecedented photostability and fatigue resistance over at least 16 cycles of photoconversion.Fil: Diaz, Sebastian Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Menéndez, Guillermo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Etchehon, Maria Herminia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; ArgentinaFil: Giordano, Luciana. Max Planck Institute for Biophysical Chemistry; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jovin, Thomas M.. Max Planck Institute for Biophysical Chemistry; AlemaniaFil: Jares, Elizabeth Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Centro de Investigaciones en Hidratos de Carbono; Argentin