CC BY
3ALT'23
The 30th International Conference on Advanced Laser Technologies
P-III
Prof. Igor Vlasov
Prokhorov General Physics Institute of the Russian Academy of Sciences, Moscow, Russia
Title: Diamond nanothermometer
Abstract
Future progress in studying intracellular thermodynamics needs an instrumentation revolution allowing local control of thermogenesis at micro/nanoscale, control of heat dissipation and heat energy conversion to other electrochemical energy types [1]. Nanodiamonds hosting temperature-sensing centers constitute a closed thermodynamic system. Such a system prevents direct contact of the temperature sensors with the environment making it an ideal environmental insensitive nanosized thermometer. A new design of a diamond nanothermometer, based on a luminescent nanodiamond embedded into the inner channel of a glass submicron pipette is reported [2]. All-optical detection of temperature, based on spectral changes of the emission of "silicon-vacancy" (SiV) centers with temperature, is used.
Further, combining a heater and a thermometer in one unit allows one to implement ultra-local hot spot control inside living cells. For this purpose, we use a single polycrystalline diamond particle containing SiV centers. Due to the presence of amorphous carbon at its intergranular boundaries such a particle is an efficient light absorber and, when illuminated by a laser, becomes a local heat source. Thus, the designed device is capable of operating in two modes. At higher laser power, it operates as the local heater and thermometer simultaneously. At low laser excitation this device does not produce heating and operates solely as a thermometer.
The first examples of successful application of a diamond nanothermometer/nanoheater are presented. In particular:
(1) the possibility of measuring high temperature gradients (up to 20 oC/^m) with submicron spatial resolution is demonstrated [2];
(2) the significant heat release of isolated mouse brain mitochondria (up to 22 oC) during total uncoupling of transmembrane potential is revealed [3];
(3) the local heating of 11-12 °C next to individual HeLa cells and neurons, isolated from the mouse hippocampus, is shown to change the intracellular distribution of the calcium ion concentration [4]. This work was supported by Russian Science Foundation, grant No 23-14-00129 .
