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RESEARCH PRODUCT
Water-soluble, cyclodextrin-functionalized semiconductor nanocrystals: Preparation and pH-dependent aggregation and emission properties
Thomas BaschéTing RenRonny HeiselRenguo XieMichael MaskosGerhard WenzMirsada SejficChristian SchererKarl FischerWolfgang Schärtlsubject
chemistry.chemical_classificationAqueous solutionPhotoluminescenceCyclodextrinInorganic chemistryBiophysicsQuantum yieldNanoparticleGeneral ChemistryCondensed Matter PhysicsBiochemistryAtomic and Molecular Physics and OpticschemistryNanocrystalChemical engineeringMoleculeParticle sizedescription
Abstract Using peramino-functionalized β-cyclodextrin molecules for phase.transfer of hydrophobic CdSe multishell nanocrystals into water, we obtained hydrophilic nanoparticles with high quantum yield (up to 50%). At pH > 9, the aqueous solution of these nanocrystals remained stable for several months. The nanoparticles showed a strong influence of the pH of the aqueous solution on the emission of the nanocrystals: the quantum yield varied reversible from ∼10% at pH=6 to ∼50% at pH=14, an effect which according to particle size characterization by dynamic light-scattering and asymmetric flow field-flow fractionation has mainly been attributed to reversible partial aggregation of the hydrophilic nanocrystals at lower pH-values. Additionally, prolonged irradiation in the presence of oxygen led to a strong enhancement of the photoluminescence intensity of the nanocrystals.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2009-12-01 | Journal of Luminescence |