Fluorescent organosilica micro- and nanoparticles with controllable size

This paper reports on the synthesis of uniformly dye-doped organosilica particles with narrow size distribution. The particle size can be controlled from tenths of nanometers up to several micrometers, whilst still maintaining monodispersity. Microparticles were observed to swell in various solvents up to ∼2.5 times their original volume, suggesting the presence of a gel-like internal structure. As shown by confocal microscopy, this morphological control of particle swelling has important implications for the encoding of the nano/micro particles with organic dyes, such as rhodamine B isothiocyanate. Swelling allows the dye to penetrate the organosilica matrix and produce uniformly dye-doped nano- and microparticles. Finally, we suggest a coagulation model for the particle formation which significantly differs from conventional Stöber synthesis.

Graphical abstractDye-doped, functionalised organosilica micro- and nanoparticles with narrow size distribution were fabricated. The particle size can be controlled from tenths of nanometers up to several micrometers. A coagulation model for the particle formation has been suggested.Figure optionsDownload full-size imageDownload as PowerPoint slide