Highly sensitive methods for detecting biomolecules based on multiple quantum dots

Quantum dot-doped nanoparticles, each of the quantum dot-doped nanoparticles comprises:

• a core particle, wherein the core particle is a polymer or inorganic material;
• a quantum dot-embedded layer, wherein the quantum dot-embedded layer consists of first multiple quantum dots bound to the outer surface of the core particle and the first multiple quantum dots surround the entire surface of the core particle;
• a silica/quantum dot composite shell, wherein the silica/quantum dot composite shell comprises second multiple quantum dots and a silica and surrounds the quantum dot-embedded layer;
• a first material comprising functional groups at opposite ends of the first material;
• and
• a second material comprising functional groups at opposite ends of the second material,
• wherein,
• the first material is present between the core particle and the first multiple quantum dots, and
• each of the first multiple quantum dots is bonded to one of the functional groups of the first material and the outer surface of the core particle is bonded to another of the functional groups of the first material such that each of the first multiple quantum dots is covalently bonded to the core particle.