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Compact Quantum-Dot Microbeads with Sub-Nanometer Emission Linewidth.

ABSTRACT: Fluorescent microbeads are widely used for applications in life sciences and medical diagnosis. The spectral contrast and sharpness of photoluminescence are critical in the utilities of microbeads for imaging and multiplexing. Here, we demonstrate microbeads capable of generating single-peak laser emission with a sub-nanometer linewidth. The microbeads are made of quantum dots that are tightly packed and crosslinked via ligand exchange for high optical gain and refractive index as well as material stability. Bright single-mode lasing with no photobleaching is achieved with particle diameters as small as 1.5 μm in the air. Sub-nm lasing emission is maintained even inside high-index surroundings, such as organic solvents and biological tissues. Feasibility of intracellular tagging and multi-color imaging in vivo is demonstrated.

SUBMITTER: Kim KH

PROVIDER: S-EPMC9000203 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Compact Quantum-Dot Microbeads with Sub-Nanometer Emission Linewidth.

Kim Kwon-Hyeon KH Dannenberg Paul H PH Yan Hao H Cho Sangyeon S Yun Seok-Hyun SH

Advanced functional materials 20210827 48

Fluorescent microbeads are widely used for applications in life sciences and medical diagnosis. The spectral contrast and sharpness of photoluminescence are critical in the utilities of microbeads for imaging and multiplexing. Here, we demonstrate microbeads capable of generating single-peak laser emission with a sub-nanometer linewidth. The microbeads are made of quantum dots that are tightly packed and crosslinked via ligand exchange for high optical gain and refractive index as well as materi ...[more]

PMID: 35418816

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