| Popis: |
Gold nanoparticles (Au NP ) with carboxyl groups on their surface were used in combination with PAH for the layer-by-layer coating of CaCO 3 microparticles, followed by the dissolution of the CaCO 3 core. SEM, TEM, and confocal microscopy are used to characterize the hybrid nanoparticles/polyelectrolyte capsules. As the Au NP have carboxyl groups on their surface, their charge density is pH dependent; therefore, the capsules exhibit a pH- dependent swelling and can be deconstructed both at low and high pH. By covalent cross-linking of the carboxyl groups of the Au NP and the amino groups of the PAH, it is possible to suppress the pH-responsive behavior. Au NP are used as activation centers using IR light and this ability is used to release encapsulated material from the nanoparticles/polyelectrolyte capsules as well as for the enhancement of detection and imaging of such capsules by Raman microspectrosopy. |
