Core-shell nanoparticles with multiple cores and method for fabricating them
The present invention is directed toward core-shell nanoparticles, each comprising a ligand-capped metal shell surrounding a plurality of discrete, nonconcentric, metal-containing cores. Methods of making and using these nanoparticles are also disclosed.
1. Core-shell nanoparticles, each core-shell nanoparticle comprising:
a shell containing a gold-silver mixture;
a plurality of discrete, nonconcentric, cores containing an iron-cobalt mixture, each core being within and surrounded by said shell; and
a ligand cap over said shell.
2. The core-shell nanoparticles according to claim 1 , wherein the nanoparticles are present in a monodispersion with controlled diameters ranging from 5 nm to 100 nm.
3. The core-shell nanoparticles according to claim 1 , wherein the iron in the core is an iron oxide which is magnetic, paramagnetic, or superparamagnetic.
4. The core-shell nanoparticles according to claim 1 , wherein the iron in the core is an iron oxide-containing core comprising a compound selected from the group consisting of Fe 3 O 4 and Fe 2 O 3 .
5. The core-shell nanoparticles according to claim 4 , wherein the iron in the core is an iron oxide-containing core comprising Fe 2 O 3 .
6. The core-shell nanoparticles according to claim 1 , wherein the ligand cap is selected from the group consisting of decanethiolate, oleylamine, oleic acid, acrylates, N,N-trimethyl(undecylmercapto)ammonium (TUA), tetrabutylammonium tetrafluoroborate (TBA), tetramethylammonium bromide (TMA), cetyltrimethylammonium bromide (CTAB), citrates, poly methacrylate, ascorbic acid, DNA, 2-mercaptopropionic acid (MPA), 3-mercaptopropionic acid (MPA), 11-mercaptoundecanoic acid (MUA), 10-mercaptodecane-1-sulfonic acid, 16-mercaptohexadecanoic acid, diimide, N-(2-mercaptopropionyl)glycine (tiopronin), 2-mercaptoethanol, 4-mercapto-1-butanol, dodecyl sulfate, amino acids, homocysteine, homocystine, cysteine, cystine, glutathione, mercaptobenzoic acid (MBA), Protein A, bovine serum albumin (BSA), and anti-rabbit-IgG (Ab).
7. The core-shell nanoparticles according to claim 6 , wherein the ligand cap is selected from the group consisting of decanethiolate, oleylamine, and oleic acid.
8. The core-shell nanoparticles according to claim 7 , wherein the ligand cap is decanethiolate.
9. The core-shell nanoparticles according to claim 7 , wherein the ligand cap is oleylamine.
10. The core-shell nanoparticles according to claim 7 , wherein the ligand cap is oleic acid.
11. The core-shell nanoparticles according to claim 1 further comprising:
a first binding material bound to the ligand-capped shell.
12. The core-shell nanoparticles according to claim 11 , wherein the first binding material is selected from the group consisting of proteins, peptides, antibodies, and antigens.