Thermo-Chromium: A Contactless Optical Molecular Thermometer

Area of Science:

• Inorganic Chemistry
• Materials Science
• Physical Chemistry

Background:

• Chromium(III) complexes exhibit unique photophysical properties.
• Dual emission from excited states is a rare phenomenon.
• Molecular thermometers offer precise temperature measurements.

Purpose of the Study:

• To investigate the excited-state potential-energy landscape of a chromium(III)-based dye, [1]3+ ([Cr(ddpd)2]3+).
• To explore the potential of [1]3+ as a molecular ratiometric thermometer.
• To develop nanodimensional thermometers for physiological conditions.

Main Methods:

• Synthesis and characterization of the chromium(III)-based dye [1]3+.
• Spectroscopic analysis of dual emission properties.
• Temperature-dependent emission studies in organic and aqueous media.
• Incorporation of [1]3+ into nanocarriers (polystyrene nanoparticles, solutol micelles).

Main Results:

• The dye [1]3+ exhibits strong dual emission in the near-infrared region.
• The temperature dependence of dual emission enables ratiometric thermometry from 210-373 K.
• [1]3+ incorporated into nanocarriers functions as a nanodimensional thermometer under physiological conditions.

Conclusions:

• The chromium(III)-based dye [1]3+ is a highly effective molecular ratiometric thermometer.
• This technology can be applied in organic, aqueous, and physiological environments.
• Nanocarrier incorporation enables advanced applications in nanomedicine and sensing.