Dual Visible and Near-Infrared Luminescent Silica Nanoparticles. Synthesis and Aggregation Stability

Abstract

Novel silica nanoparticles exhibiting near-infrared (NIR) and dual NIR-visible emission were synthesized according to reverse microemulsion procedure through the encapsulation of Yb(III) complex with p-sulfonatothiacalix[4]arene (Yb) and [Ru(dipy)3]Cl2 (Ru) as NIR- and visible-emitting luminophores into silica matrix. The synthesis was carried out at various Yb:Ru molar ratio. The numbers of Ru and Yb complexes per one nanoparticle were calculated from both fluorimetric and inductively coupled plasma atomic emission spectroscopy data. The dynamic light scattering measurements of aqueous dispersions of Yb, Ru, and Ru−Yb nanoparticles elucidate the relationship between the complexes inserted into nanoparticles and their aqueous dispersity. The transmission electron microscopy images were used to measure the size of the nanoparticles. The atomic force microscopy images reveal the different aggregation morphology of Yb- and Ru-doped nanoparticles.

Silica nanoparticles with a substrate switchable luminescence

“…The synthesized nanoparticles were doped with different ratio of Ru:Yb (2:1, 1:1, 0.9:1, 0.5:1, 0.3:1) and were analyzed by fluorimetry, electrophoresis, dynamic light scattering, microscopy and atomic emission spectroscopy methods [13]. The analysis of Yb-centered emission intensity of nanoparticles indicates no correlation between the intensity of Yb-centered luminescence and Yb:Ru molar ratio (figure 4b).…”

A facile synthetic route to convert Tb(iii) complexes of novel tetra-1,3-diketone calix[4]resorcinarene into hydrophilic luminescent colloids

“…[17][18][19][20] The Tb(III) complex with p-sulfonatothiacalix [4]arene should be mentioned as a fine example of a highly luminescent water soluble complex, [19][20][21] which nevertheless should be protected or encapsulated in some polymeric matrix to be applied for marking and sensing. 22,23 Indeed, calixarene based lanthanide complexes, which combine water solubility, enhanced antennae effect on lanthanide-centered luminescence and high stability in aqueous buffer solutions, are very rare if at all existent.…”

“…The doping of water insoluble lanthanide complexes into nanoparticles with their further hydrophilic coating is a promising alternative to covalent modification of ligands with ionic groups as a route to improve water solubility. 1,6,[22][23][24][25][26] Moreover, the core-shell morphology of nanoparticles leads to a route to gain biocompatibility by encapsulation of hazardous a A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Center luminophores in a biocompatible polymeric matrix, which affords a biomedical application of the nanoparticles. Although silica coating is a well-developed route to make core-shell nanoparticles, including those with lanthanide-centered luminescence, its shortcomings are worth noting.…”

The effect of the core morphology of Eu(III)-doped nanoparticles on the ion exchange versus energy transfer between Eu(III) in the core and Cu(II) ions at the interface

“…The coating of lanthanide complexes by silica or polymeric shell is the common way to prevent their degradation in solutions and bioenvironment (Enrichi et al 2010;Gao et al 2009;Jiang et al 2010;Binnemans et al 2004;Wu et al 2008;Härmä et al 2008;Yin et al 2011;Mustafina et al 2009Mustafina et al , 2011. The insertion of various f or both d and f ions into silica nanoparticles should be mentioned as fine examples of gaining to NPs dual luminescence or luminescent and magnetic properties (Fedorenko et al 2010;Shi et al 2010). It is also worth noting that the interfacial binding of metal ions with their further removing from the interface of luminescent NPs by some chelating anions can be successfully applied in the sensing of these anions, as it was demonstrated in the works Seo et al 2010;He et al 2010; Barja and Aramendría 2008).…”