Fluorescent silica nanoparticles for medical diagnostics

Synthesis of nanoparticles stable, monodisperse and perfectly soluble in water that can be used as markers in bio-analytical technologies, in imaging techniques, with potential therapeutic use by photothermal and photodynamic therapy and in the development of chemosensors.

Title of the patent Active particles for bio-analytical applications and methods for their preparation
Thematic area Chemistry and biotechnology
Ownership Alma Mater Studiorum - Università di Bologna
Inventors Luca Prodi, Sara Bonacchi, Riccardo Juris, Marco Montalti, Enrico Rampazzo, Nelsi Zaccheroni
Protection Europe, USA, Australia, Brazil, China
Licensing status Available for licensing agreement
Keywords Nanoparticles, nanospheres, silica, pluronic F127, diblock copolymers, luminescent, fluorescence, probes, core-shell
Filed on Jul 31, 2008

Great efforts have been recently made towards the design of new luminescent labeling materials for imaging and medical diagnostics. Silica nanoparticles are the subject of a great attention in this context, since they are intrinsically nontoxic, and they can offer very high luminescence signal and high stability. Our patents present a new methodology for the one-pot synthesis of luminescent and electro-chemiluminescent silica nanoparticles, and the procedures for their derivatization for labelling biomolecules such as proteins, DNA, and antibodies.

Patent describes the synthesis of luminescent nanoparticles with a diameter in the 10-100 nm range (with high monodispersity), presenting a core-shell structure made by silica and PEG (polyethylenglycole). In particular, the core of the nanoparticle is constituted by a silica matrix containing a number of a specific (organic, organometallic or inorganic) dye presenting the desired luminescent features (including excitation and emission wavelength). In addition, the polyossethylenic units can present, at their ends, functional groups that can be used for labeling biomolecules or for the derivatization of surfaces (such as electrodes). These nanoparticles can be effectively used as labels for medical diagnostics (unprecedented signal-to-noise ratios can be obtained, allowing the design, inter alia, of PCR-free methodologies for DNA analysis) and optical imaging (these nanoparticles have shown luminescent properties superior to what is today commercially available).

As described, the nanoparticles presented have very promising features. In addition, to our knowledge, our methodology is the only one allowing to produce derivatized luminescent nanostructures in a one pot procedures, starting form low cost materials. This combination makes our procedure a very convenient one as far as the economic aspects are taken into consideration. In addition, no disposal concerns are related to silica nanoparticles, contrary to what found for the so called quantum dots (that are also intrinsically toxic), that are marketed today. To conclude, our nanoparticles can have several advantages respect to what is now commercially available, a market that is observing a strong increase: in particular high performances, low cost, and no disposal concerns.