Composite particles, coated particles, method for producing composite particles, ligand-containing solid phase carrier and method for detecting or separating target substance in sample
The present invention relates to composite particles, coated particles, a method of producing composite particles, a ligand-containing solid phase carrier, and a method of detecting or separating a target substance in a sample. The above described composite particles each contains an organic polymer and inorganic nanoparticles, wherein the content of the inorganic nanoparticles in the composite particles is more than 80% by mass, and wherein the composite particles have a volume average particle size of from 10 to 1,000 nm.
1. A method of producing composite particles, the method comprising:
mixing a magnetic fluid, a monomer and a polymerization initiator to prepare a monomer mixed liquid so that a content of magnetic nanoparticles is more than 80% by mass with respect to 100% by mass of a material for forming the composite particles in the monomer mixed liquid;
dispersing the monomer mixed liquid to prepare an emulsion; and
polymerizing the monomer in the emulsion to produce composite particles that comprise magnetic nanoparticles in an amount of more than 80% by mass.
2. The method of claim 1 , wherein the composite particles have a volume average particle size of from 10 to 1,000 nm.
3. The method of claim 1 , wherein the composite particles have a coefficient of variation of the volume average particle size of 20% or less.
4. The method of claim 1 , wherein the magnetic nanoparticles are present in an amount of more than 80% by mass to 95% by mass.
5. The method of claim 1 , wherein the magnetic nanoparticles have a volume average particle size of from 5 to 25 nm.
6. The method of claim 1 ,
wherein the magnetic fluid comprises at least one selected from the group consisting of a surfactant, an acid group-containing compound, an amino group-containing compound, a silane group-containing compound and a titanium atom-containing compound, and
wherein the composite particles comprise at least one selected from the group consisting of a surfactant, an acid group-containing compound, an amino group-containing compound, a silane group-containing compound and a titanium atom-containing compound.
7. The method of claim 1 , wherein the magnetic nanoparticles are metal oxide particles.
8. The method of claim 1 , wherein the monomer is a monomer such that the resulting polymer obtained is a hydrophobic polymer, and wherein the composite particles have surfaces to which at least one ligand can be physically adsorbed.
9. The method of claim 1 , wherein the monomer is a monomer containing a reactive functional group, and wherein the composite particles have surfaces to which at least one ligand can be chemically bound.