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Synthesis, encapsulation, purification and coupling of single quantum dots in phospholipid micelles for their use in cellular and in vivo imaging

Nature Protocols volume 2, pages 2383–2390 (2007)Cite this article

Abstract

A detailed protocol for the synthesis of core/shell semiconductor nanocrystal, their encapsulation into phospholipid micelles, their purification and their coupling to a controlled number of small molecules is given. The protocol for the core/shell quantum dot (QD) CdSe/CdZnS synthesis has been specifically designed with two constraints in mind: green and reproducible core/shell QD synthesis with thick shell structure and QDs that can easily be encapsulated in poly(ethylene glycol)-phospholipid micelles with one QD per micelle. We present two procedures for the QD purification that are suitable for the use of QD micelles for in vivo imaging: ultracentrifugation and size-exclusion chromatography. We also discuss the different coupling chemistry for covalently linking a controlled number of molecules to the QD micelles. The total time durations for the different protocols are as follows: QD synthesis: 6 h; encapsulation: 15 min; purification: 1–4 h; coupling: reaction dependent.

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Figure 1
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Figure 5: Schematics of fluorescein–QD conjugation protocol.
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Figure 7: Evolution of photoluminescence excitation spectra during shell-growth.
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Figure 10: Absorption and emission spectra of QD, fluorescein and QD–fluorescein adducts.

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Authors and Affiliations

  1. Laboratoire Photons et Matière, CNRS UPRA5, ESPCI, 10, rue Vauquelin, Paris, 75231, Cedex 05, France

    Olivier Carion, Benoît Mahler, Thomas Pons & Benoit Dubertret

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  1. Olivier Carion
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  2. Benoît Mahler
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  3. Thomas Pons
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  4. Benoit Dubertret
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Correspondence to Benoit Dubertret.

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Carion, O., Mahler, B., Pons, T. et al. Synthesis, encapsulation, purification and coupling of single quantum dots in phospholipid micelles for their use in cellular and in vivo imaging. Nat Protoc 2, 2383–2390 (2007). https://doi.org/10.1038/nprot.2007.351

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