Structural control of the hybrid colloids by cooperative assembly of PS-b-PAA and semiconductor nanoparticles from the solvent aspects

Well-defined polymer/inorganic nanoparticle (NP) hybrids are of vital importance to the development of nanomaterials with desired optical, electric, magnetic, and many other properties. We demonstrate the efficient incorporation of n -trioctylphosphine oxide (TOPO)-coated CdSe quantum dots (QDs) into polystyrene- b -polyacrylic acid (PS- b -PAA) colloids by a “solution phase self-assembly” approach. Driven by the hydrophobic interactions, the CdSe QDs are homogeneously encapsulated in the hybrid colloids. The sizes of the hybrid colloids with different structures, i.e., simple spherical micelles and big compound micelles, are tuned from 45 to 126 nm by varying the THF content in the cosolvents of THF and DMF, as well as changing the content or addition rate of selective solvent (water). The PS- b -PAA@CdSe QD hybrid colloids, which show brightly green fluorescence, can be endocytosed into biological cells and be released from the cells evolutionally, indicating their potential applications in biological imaging, labeling, and sensing, among others.