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Design of fluorescent nanocapsules as ratiometric nanothermometers.

ABSTRACT: We have developed a novel design of optical nanothermometers that can measure the surrounding temperature in the range of 20-85?°C. The nanothermometers comprise two organic fluorophores encapsulated in a crosslinked polymethacrylate nanoshell. The role of the nanocapsule shell around the fluorophores is to form a well-defined and stable microenvironment to prevent other factors besides temperature from affecting the dyes' fluorescence. The two fluorophores feature different temperature-dependent emission profiles; a fluorophore with relatively insensitive fluorescence (rhodamine 640) serves as a reference whereas a sensitive fluorophore (indocyanine green) serves as a sensor. The sensitivity of the nanothermometers depends on the type of nanocapsule-forming lipid and is affected by the phase transition temperature. Both the fluorescence intensity and the fluorescence lifetime can be utilized to measure the temperature.

SUBMITTER: Zhegalova NG

PROVIDER: S-EPMC5477229 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

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Design of fluorescent nanocapsules as ratiometric nanothermometers.

Zhegalova Natalia G NG Dergunov Sergey A SA Wang Steven T ST Pinkhassik Eugene E Berezin Mikhail Y MY

Chemistry (Weinheim an der Bergstrasse, Germany) 20140713 33

We have developed a novel design of optical nanothermometers that can measure the surrounding temperature in the range of 20-85 °C. The nanothermometers comprise two organic fluorophores encapsulated in a crosslinked polymethacrylate nanoshell. The role of the nanocapsule shell around the fluorophores is to form a well-defined and stable microenvironment to prevent other factors besides temperature from affecting the dyes' fluorescence. The two fluorophores feature different temperature-dependen ...[more]

PMID: 25044240

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