Synthesis and characterization of monodisperse, mesoporous, and magnetic sub-micron particles doped with a near-infrared fluorescent dye

Journal Article · Wed Jun 15 00:00:00 EDT 2011 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2011.04.022· OSTI ID:21580103

Nooney, Robert; McDonagh, Colette; MacCraith, Brian D ^[1]

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1. Biomedical Diagnostics Institute, School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9 (Ireland)

Recently, multifunctional silica nanoparticles have been investigated extensively for their potential use in biomedical applications. We have prepared sub-micron monodisperse and stable multifunctional mesoporous silica particles with a high level of magnetization and fluorescence in the near infrared region using an one-pot synthesis technique. Commercial magnetite nanocrystals and a conjugated-NIR-dye were incorporated inside the particles during the silica condensation reaction. The particles were then coated with polyethyleneglycol to stop aggregation. X-ray diffraction, N{sub 2} adsorption analysis, TEM, fluorescence and absorbance measurements were used to structurally characterize the particles. These mesoporous silica spheres have a large surface area (1978 m{sup 2}/g) with 3.40 nm pore diameter and a high fluorescence in the near infrared region at {lambda}=700 nm. To explore the potential of these particles for drug delivery applications, the pore accessibility to hydrophobic drugs was simulated by successfully trapping a hydrophobic ruthenium dye complex inside the particle with an estimated concentration of 3 wt%. Fluorescence imaging confirmed the presence of both NIR dye and the post-grafted ruthenium dye complex inside the particles. These particles moved at approximately 150 {mu}m/s under the influence of a magnetic field, hence demonstrating the multifunctionality and potential for biomedical applications in targeting and imaging. - Graphical Abstract: Hydrophobic fluorescent Ruthenium complex has been loaded into the mesopores as a surrogate drug to simulate drug delivery and to enhance the multifunctionality of the magnetic NIR emitting particles. Highlights: > Monodisperse magnetic mesoporous silica particles emitting in the near infrared region are obtained in one-pot synthesis. > We prove the capacity of such particles to uptake hydrophobic dye to mimic drug loading. > Loaded fluorescent particles can be moved under a magnetic field in a microfluidic device.

• OSTI ID: 21580103
• Journal Information: Journal of Solid State Chemistry, Vol. 184, Issue 6; Other Information: DOI: 10.1016/j.jssc.2011.04.022; PII: S0022-4596(11)00190-3; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ADSORPTION
DOPED MATERIALS
DRUGS
DYES
FLUORESCENCE
MAGNET CORES
MAGNETIC CORES
MAGNETIC FIELDS
MAGNETITE
MAGNETIZATION
NANOSTRUCTURES
PARTICLES
RUTHENIUM
RUTHENIUM COMPLEXES
SILICA
SURFACE AREA
SYNTHESIS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
COHERENT SCATTERING
COMPLEXES
DIFFRACTION
ELECTRON MICROSCOPY
ELEMENTS
EMISSION
IRON ORES
LUMINESCENCE
MAGNETIC STORAGE DEVICES
MATERIALS
MEMORY DEVICES
METALS
MICROSCOPY
MINERALS
ORES
OXIDE MINERALS
PHOTON EMISSION
PLATINUM METALS
REFRACTORY METALS
SCATTERING
SORPTION
SURFACE PROPERTIES
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENTS