Quantum Dot Thermometers Measure Temperatures Inside Single Living Cells
Small temperature differences inside individual cells affect kinetics and shift chemical equilibria, but also alter the physical state of biomaterials such as DNA and proteins. Technology for detecting such temperature variations could lead to insights into biological mechanisms related to a wide range of metabolic processes in bioenergy-relevant systems. New research has shown that quantum dots can serve as nano thermometers to measure local temperature responses inside single living cells following exposure to external chemical and physical stimuli. Quantum dots are semiconductors in the form of crystals that fluoresce with colors determined by crystal size and chemical composition. The spectral shifts in the photoluminescence produced by the quantum dots were used to map intracellular heat generation from different organelles and compartments in cells following exposure to stress from high calcium levels and cold shock. These results are the first experimental evidence for inhomogeneous intracellular temperature progression in cells. The research was carried out at the Berkeley Lab and Princeton University and published in ACS Nano.
Yang, J.-M., H. Yang, and L. Lin. 2011. “Quantum Dot Nano Thermometers Reveal Heterogeneous Local Thermogenesis in Living Cells,” ACS Nano 5(6), 5067-71. (DOI: 10.1021/nn201142f)