Purple-, Blue-, and Green-Emitting Multishell Alloyed Quantum Dots: Synthesis, Characterization, and Application for Ratiometric Extracellular pH Sensing
| Autor: | Kimihiro Susumu, Lauren D. Field, Igor L. Medintz, James B. Delehanty, Valle Palomo, Philip E. Dawson, Alan L. Huston, Eunkeu Oh, Michael Hunt |
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| Rok vydání: | 2017 |
| Předmět: |
Aqueous solution
Ligand Chemistry General Chemical Engineering Analytical chemistry 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Photochemistry 01 natural sciences Fluorescence 0104 chemical sciences Ion Full width at half maximum Quantum dot Materials Chemistry Surface modification 0210 nano-technology Luminescence |
| Zdroj: | Chemistry of Materials. 29:7330-7344 |
| ISSN: | 1520-5002 0897-4756 |
| Popis: | We report the synthesis of a series of CdxZn1–xSe/CdyZn1–yS/ZnS and ZnSe/CdyZn1–yS/ZnS multishell alloyed luminescent semiconductor quantum dots (QDs) with fluorescence maxima ranging from 410 to 530 nm which cover the purple, blue, and green portion of the spectrum. Their subsequent surface modification to prepare water-soluble blue-emitting QDs, characterization, and application for ratiometric pH sensing in aqueous buffers and in an extracellular environment are further described. QDs were synthesized starting from ZnSe cores, and the fluorescence peak positions were tuned by (i) cation exchange with cadmium ions and/or (ii) overcoating with CdyZn1–yS layers. The as-prepared QDs had reasonably high fluorescence quantum yields (∼30–55%), narrow fluorescence bands (fwhm ∼25–35 nm), and monodispersed semispherical shapes. Ligand exchange with hydrophilic compact ligands was successfully carried out to prepare a series of water-soluble blue-emitting QDs. QDs coated with the hydrophilic compact ligands pres... |
| Databáze: | OpenAIRE |
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