Label-free identification of single dielectric nanoparticles and viruses with ultraweak polarization forces
Autor: | Laura Fumagalli, José L. Carrascosa, Daniel Esteban-Ferrer, Ana Cuervo, Gabriel Gomila |
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Jazyk: | angličtina |
Rok vydání: | 2012 |
Předmět: |
Materials science
Electrostatic force microscope Nanoparticle Nanotechnology 02 engineering and technology Dielectric 010402 general chemistry 01 natural sciences Capsid Electric field Bacteriophage T7 Microscopy Electric Impedance General Materials Science Particle Size Polarization (electrochemistry) Nanoscopic scale Mechanical Engineering General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences Mechanics of Materials Calibration Nanoparticles 0210 nano-technology Macromolecule |
Zdroj: | Nature Materials Repositorio Institucional del Instituto Madrileño de Estudios Avanzados en Nanociencia instname |
Popis: | Label-free detection of the material composition of nanoparticles could be enabled by the quantification of the nanoparticles' inherent dielectric response to an applied electric field. However, the sensitivity of dielectric nanoscale objects to geometric and non-local effects makes the dielectric response extremely weak. Here we show that electrostatic force microscopy with sub-piconewton resolution can resolve the dielectric constants of single dielectric nanoparticles without the need for any reference material, as well as distinguish nanoparticles that have an identical surface but different inner composition. We unambiguously identified unlabelled ~10 nm nanoparticles of similar morphology but different low-polarizable materials, and discriminated empty from DNA-containing virus capsids. Our approach should make the in situ characterization of nanoscale dielectrics and biological macromolecules possible. |
Databáze: | OpenAIRE |
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