Fullerene-silica nanoparticles with improved fluorescence, preparation method thereof and use thereof

• US 8,715,738 B2
• Filed: 01/06/2009
• Issued: 05/06/2014
• Est. Priority Date: 05/21/2008
• Status: Active Grant

• Current Assignee: Korea Research Institute of Bioscience & Biotechnology
• Original Assignee: Korea Research Institute of Bioscience & Biotechnology
• Inventors: Chung, Bong Hyun, Jeong, Jinyoung, Song, Nam Woong
• Primary Examiner(s): DICKINSON, PAUL W
• Application Number:
  US12/993,908
• Publication Number:
  US 20110171097A1
• Time in Patent Office: 1,946 Days
• Field of Search: None
• US Class Current: 424/489
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 32/156 After-treatment
• CPC Class Codes: C09K 11/02 Use of particular materials as binders, particle coatings or suspension media therefor
• CPC Class Codes: C09K 11/65 containing carbon in organic compounds C09K11/06

Abstract

The present invention relates to fullerene-silica nanoparticles with improved fluorescence, a preparation method of the fullerene-silica nanoparticles, and use thereof. More specifically, the present invention relates to fullerene-silica nanoparticles with improved fluorescence in which fullerene and silica are covalently linked, a preparation method of the fullerene-silica nanoparticles, and use thereof. The preparation method of the fullerene-silica nanoparticles comprises the steps of: adding a surfactant to a non-polar organic solvent and a polar solvent and stirring them to form reverse micelles (step 1); adding fullerene to the reverse micelles formed in the step 1 and stirring them (step 2); and adding a silica precursor and a catalyst to a reaction solution containing the fullerene prepared in the step 2 and stirring them to prepare fullerene-silica nanoparticles (step 3). According to the present invention, fullerene-silica nanoparticles in the form of a uniform spherical shape of tens of nanometers can be prepared. As such prepared fullerene-silica nanoparticles have a large surface area due to a nanometer-sized structure, they have good reactivity. Compared with heavy metals or metal nanoparticles, the fullerene-silica nanoparticles, because of using silica, are harmless to a living body. Further, as the fullerene-silica nanoparticles exhibit strong fluorescence, they can be used as a contrast agent for in-vivo imaging or as a drug delivery carrier.

Claims

1. Fullerene-silica nanoparticles with fluorescence having a uniform spherical shape in which fullerene and silica are directly linked through C—

O—

Si—

[O—

Si]_n—

O—

C covalent bonds without linkers,

wherein n=0 or 1, and the fullerene has a plurality of C—

OH terminal substituents from the result of reaction between the fullerene and ammonium hydroxide, wherein the C is from the fullerene and the OH is from the ammonium hydroxide.

2. The fullerene-silica nanoparticles of claim 1, wherein the fluorescence properties comprise optical properties to absorb light in visible ray and ultraviolet ray regions and to emit light in the visible ray region.

3. A method for preparing the fullerene-silica nanoparticles of claim 1, the method comprising steps of:

adding a surfactant to a non-polar organic solvent and a polar solvent and stirring them to form reverse micelles (step

     1);

adding fullerene to the reverse micelles formed in the step 1 and stirring them (step

     2); and

adding a silica precursor and a catalyst to a reaction solution containing the fullerene prepared in the step 2 and stirring them to prepare fullerene-silica nanoparticles (step

     3).

4. The method of claim 3, wherein the non-polar organic solvent in the step 1 is selected from the group consisting of toluene, cyclohexane, heptane, isooctane, and decane.

5. The method of claim 3, wherein the polar solvent in the step 1 is an alcohol.

6. The method of claim 5, wherein the alcohol is butanol, heptanol, or hexanol.

7. The method of claim 3, wherein the surfactant in the step 1 is a nonionic surfactant or an anionic surfactant,

wherein

the nonionic surfactant is TritonX-100 (C₁₄H₂₂O(C₂H₄O)_n) or nonylphenyl pentaethylene glycol (NP4, NP5, NP9);

and

the anionic surfactant is sodium di(2-ethylhexyl)sulfonic succinate or sodium dodecyl sulfate as a sulfate.

8. The method of claim 3, wherein co-surfactant is further included to regulate an interface strength.

9. The method of claim 3, wherein a mixing ratio of the nonpolar organic solvent:

polar solvent;

surfactant is 2˜

8;

1˜

5;

1˜

3.

10. The method of claim 3, wherein the fullerene of the step 2 is C60, C70, C80 or C90 fullerenes.

11. The method of claim 3, wherein the fullerene in the step 2 is added by being dissolved in a solvent selected from the group consisting of toluene, cyclohexane, heptane, and benzene.

12. The method of claim 3, wherein a concentration of the fullerene in the step 2 is 0.00001˜

0.1 wt %.

13. The method of claim 3, wherein the silica precursor in the step 3 is tetraethyl orthosilicate (TEOS), tetramethyl orthosilicate (TMOS), or tetrapropyl orthosilicate (TPOS).

14. The method of claim 3, wherein the catalyst in the step 3 is ammonia aqueous solution.

15. The method of claim 14, wherein the ammonia aqueous solution is 25˜

30 weight % ammonia aqueous solution.

16. A bioimaging agent comprising the fullerene-silica nanoparticles of claim 1.