Fig. 4.

Ratiometric thermometry in vivo. a Schematic illustration of the setup for ratiometric thermometry in vivo. b The standard curve for temperature evaluation in vivo measured with TTA-Nd-NPs probe in tissue phantom. c Ratiometric thermometry based on TTA-Nd-NPs in an inflammatory mode. The bright-filed image showed arthritis in the swollen right leg of a Kunming mouse stimulated with carrageenan (1 wt%, 100 µL) while the left leg was normal as control. The ratiometric image revealed the luminescent ratios and evaluated temperature distributions in the two legs. The TTA-UCL and reference signals were acquired in channel I (485–575 nm) and channel II (980–1300 nm) of the in vivo imaging system, respectively