semiconductor nanoparticles having high luminescence properties that are preferable for applications and uses of biotechnology are provided . with the use of electric charges on the surfaces of particles , the particles and selected polymers are allowed to electrostatically bind to each other , such that the surfaces of the particles are coated . the polymers are allowed to crosslink to each other , resulting in the improved durability of the particles . further , functional groups contained in the polymers are exposed on the surfaces of the particles . accordingly , semiconductor nanoparticles that are preferably utilized for applications such as staining and labeling of biopolymers have been synthesized .