A class of core-shell-type fluorescent nanospheres with a particle diameter less than 40 nm,which emit orange,yellow,green and cyan light,respectively,were prepared.In fabricating strategy,the water-insoluble,photo-thermostable fluorescent dye molecules are molecularly dispersed and embedded in the nanoscale crosslinked polymeric matrix via a modified miniemulsion polymerization process,and then the biocompatible shells are achieved by a seeded polymerization technique.These obtained nanospheres are uniform in size,highly photostable,of high chemical resistance and high fluorescence quantum-yield.
