Mapping Intracellular Temperature Using Green Fluorescent Protein

ICFO-Institut de Ciencies Fotoniques, Mediterranean Technology Park, 08860 Castelldefels (Barcelona), Spain.
Nano Letters (Impact Factor: 13.59). 03/2012; 12(4):2107-11. DOI: 10.1021/nl300389y
Source: PubMed


Heat is of fundamental importance in many cellular processes such as cell metabolism, cell division and gene expression. (1-3) Accurate and noninvasive monitoring of temperature changes in individual cells could thus help clarify intricate cellular processes and develop new applications in biology and medicine. Here we report the use of green fluorescent proteins (GFP) as thermal nanoprobes suited for intracellular temperature mapping. Temperature probing is achieved by monitoring the fluorescence polarization anisotropy of GFP. The method is tested on GFP-transfected HeLa and U-87 MG cancer cell lines where we monitored the heat delivery by photothermal heating of gold nanorods surrounding the cells. A spatial resolution of 300 nm and a temperature accuracy of about 0.4 °C are achieved. Benefiting from its full compatibility with widely used GFP-transfected cells, this approach provides a noninvasive tool for fundamental and applied research in areas ranging from molecular biology to therapeutic and diagnostic studies.

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Available from: Romain Quidant, Feb 21, 2014
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    • "This width is therefore related to the measurement conditions rather than to the intrinsic spatial resolution, which is limited only by the probe volume of ≈ 100 nm corresponding to the nanodiamond size. We note that direct mapping of the temperature profile during constant heating could be achieved by employing an additional heating laser, thereby providing a way to investigate photo-induced heating with a spatial resolution drastically better than the current, diffractionlimited techniques [48] [49]. "
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