Semiconductor nanoparticles and fluorescent probe for biological labeling
Semiconductor nanoparticles of the present invention are particles each having a core-shell structure that includes a core and a shell surrounding the core. The core includes (AgIn) x Zn 2(1-x) S 2 (0.4≦x≦0.95 holds). The shell includes ZnS or ZnO, and the semiconductor nanoparticles each have at least one hydrophilic functional group on a surface of the shell. As the hydrophilic functional group, for example, a carboxyl group or a sulfo group may be mentioned. Since having a low toxicity and a high emission quantum yield, the semiconductor nanoparticles as described above may be used for a fluorescent probe for biological labeling.
1. Semiconductor nanoparticles each having a core-shell structure that includes a core and a shell surrounding the core,
wherein the core includes (AgIn) x Zn 2(1-x) S 2 (0.4≦×≦0.95),
the shell includes ZnS or ZnO, and
the semiconductor nanoparticles each have a hydrophilic functional group on a surface of the shell.
2. The semiconductor nanoparticles according to claim 1 ,
wherein 0.8≦x≦0.9.
3. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 2 .
4. The semiconductor nanoparticles according to claim 1 ,
wherein the hydrophilic functional group is a carboxyl group or its salt or a sulfo group or its salt.
5. The semiconductor nanoparticles according to claim 4 ,
wherein the hydrophilic functional group is a functional group of a bifunctional molecule having said hydrophilic functional group (first functional group) and a functional group (second functional group) which is bonded to the surface of the shell.
6. The semiconductor nanoparticles according to claim 5 ,
wherein the second functional group contains a sulfur atom or a nitrogen atom.
7. The semiconductor nanoparticles according to claim 6 ,
wherein the second functional group contains a sulfur atom and is a mercapto group; a group having a disulfide bond; a group having a sulfide bond; a pyridylthio group; or a dithiocarboxyl group.
8. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 7 .
9. The semiconductor nanoparticles according to claim 6 ,
wherein the second functional group contains a nitrogen atom and is an imino group, an amide group, an imide group, or a pyridyl group.
10. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 9 .
11. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 6 .
12. The semiconductor nanoparticles according to claim 5 ,
wherein the bifunctional molecule is 3-mercaptopropionic acid, 4-mercaptobutyric acid, 2-mercaptomethane sulfonic acid, 2-mercaptoethane sulfonic acid, 3-mercaptopropane sulfonic acid, or 2-mercaptoethane sodium sulfonate.
13. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 12 .
14. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 5 .
15. A fluorescent probe for biological labeling, comprising:
conductor nanoparticles according to claim 4 .
16. A fluorescent probe for biological labeling, comprising:
the semiconductor nanoparticles according to claim 1 .