Kim, Taewan Xu, Meng Lee, Young Jun Ku, Kang Hee Shin, Do Joong Lee, Doh C. Jang, Se Gyu Yun, Hongseok Kim, Bumjoon J. 2024-01-19T14:30:26Z 2024-01-19T14:30:26Z 2021-10-21 2021-07 1613-6810 https://pubs.kist.re.kr/handle/201004/116789 The precise self-assembly of block copolymers (BCPs) and inorganic nanoparticles (NPs) under 3D confinement offers microparticles with programmable nanostructures and functionalities. Here, fluorescence-switchable hybrid microspheres are developed by forming doubly alternating arrays of Au NPs and CdSe/ZnS quantum dots (QDs) within polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) BCP domains. These doubly alternating arrays afford controlled nonradiative energy transfer (NRET) between the QDs and Au NPs that is dependent on the layer-to-layer distance. Solvent-selective swelling of the hybrid particles tunes the distance between layers, modulating their NRET behavior and affording switchable fluorescence. The particle fluorescence is "OFF" in water through strong NRET from the QDs to Au NPs, but is "ON" in alcohols due to the increased distance between the Au NP and QD arrays in the swollen P4VP domains. The experimentally observed NRET intensity as a function of interparticle distance shows larger quenching efficiencies than those theoretically predicted due to the enhanced quenching within a 3D-confined system. Finally, the robust and reversible fluorescence switching of the hybrid particles in different solvents is demonstrated, highlighting their potentials for bioimaging, sensing, and diagnostic applications. English WILEY-V C H VERLAG GMBH GOLD NANOPARTICLES QUANTUM DOTS DIBLOCK COPOLYMERS FACILE SYNTHESIS ENERGY-TRANSFER SHAPE LOCATION MORPHOLOGIES ASSEMBLIES ENTROPY Fluorescence Switchable Block Copolymer Particles with Doubly Alternate-Layered Nanoparticle Arrays Article 10.1002/smll.202101222 1 SMALL, v.17, no.28 SMALL 17 28 scie scopus 000659729900001 2-s2.0-85107482952 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article GOLD NANOPARTICLES QUANTUM DOTS DIBLOCK COPOLYMERS FACILE SYNTHESIS ENERGY-TRANSFER SHAPE LOCATION MORPHOLOGIES ASSEMBLIES ENTROPY block copolymer particles fluorescence switching hybrid particles nanoparticle array nonradiative energy transfer