One-Pot Synthesis of Cy5-Encapsulated Photostable Fluorescent Silica Nanoparticles for Bioimaging

Abstract

A new type of Cy5-encapsulated photostable fluorescent silica nanoparticles (FSNPs) bearing positive charges have been successfully fabricated by a reverse microemulsion synthesis in one-pot. The Cy5 dye containing four primary amines are embedded into silica via covalent bonds through a silane coupling agent (GPTMS), followed by co-condensation with tetraethylorthosilicate. The uniform-sized, spherical and monodispersed FSNPs have high fluorescence intensity and photostability. The FSNPs exhibit high stability, good biocompatibility as well as low cytotoxicity. These FSNPs can be internalized into live cells and thus fluorescently label the cells. This study provides a simple synthesis approach that can be applied to other water-soluble and amino-modified organic dye molecules for biological targeting and fluorescent cell imaging.

Synthesis of highly stable cyanine-dye-doped silica nanoparticle for biological applications

“…More importantly, it has been reported that incorporation of cyanine dyes into silica nanoparticles could tremendously improve the photo-stability and brightness of cyanine dyes [23]. In search of cyanine dye-doped silica nanoparticles, to the best of our knowledge, there are only few reports on the success of encapsulating cyanine dyes inside silica nanoparticles [24][25][26][27][28][29][30][31][32]. Within these reports, either more stable dyes [24,26,28,30,31] or biomaterials [29] were used to assistant the formation of fluorescent silica nanoparticles.…”

“…In search of cyanine dye-doped silica nanoparticles, to the best of our knowledge, there are only few reports on the success of encapsulating cyanine dyes inside silica nanoparticles [24][25][26][27][28][29][30][31][32]. Within these reports, either more stable dyes [24,26,28,30,31] or biomaterials [29] were used to assistant the formation of fluorescent silica nanoparticles. However, commercially available cyanine dyes are very challenging to be incorporated into silica nanoparticles, mainly because these dyes cannot tolerant the alkaline condition used in silica nanoparticle formation [24,27].…”

DDAO Controlled Synthesis of Organo-Modified Silica Nanoparticles with Encapsulated Fluorescent Boron Dipyrrins and Study of Their Uptake by Cancerous Cells

“…During sol-gel synthesis, hydrolysis and polycondensation of alkoxysilanes occur, forming solid nanoparticles, which will grow around the surface of the micelles [ 30 ]. The W/O system is suitable for the fixation of polar components inside the silica particle [ 31 ] while the oil-in-water (O/W) emulsion is desirable for nonpolar substances [ 32 ]. Nonpolar molecules immobilization is possible due to the hydrophobic effect using the silica matrix modified with phenyl fragments [ 33 , 34 , 35 ].…”