Synthesis of Fluorescent, Monodisperse, Colloidal Silica Particles

✍ Scribed by René Nyffenegger; Christian Quellet; Jaroslav Ricka

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 929 KB
• Volume: 159
• Category: Article
• ISSN: 0021-9797
• DOI: 10.1006/jcis.1993.1306

✦ Synopsis

The preparation of colloidal, fluorescently labeled silica particles by controlled hydrolysis and polycondensation of tetramethoxysilane (TMOS) in the presence of a silylated fluorescein derivative is described. Monodisperse particles with average radii of (80 \mathrm{~nm}) and a narrow size distribution with a standard deviation lower than (8 %) are obtained using the seeded growth technique, whereas homogeneous nucleation yields particles with a bimodal size distribution. The apparent degree of labeling ranges from (5 \times 10^{-8}) to (2 \times 10^{-6} \mathrm{~mol}) equivalent of fluorescein per gram of silica, depending on the labeling procedure. (1) 1993 Academic Press. Inc.