Nanoscale 3D temperature gradient measurement based on fluorescence spectral characteristics of the CdTe quantum dot probe.

The existing quantum dot temperature measurement techniques can only measure the planar temperature in the cell but fails in 3D temperature investigation. We present a novel method of measuring the 3D temperature field on nano scale, combining fluorescence spectral characteristics of the CdTe quantum dot probe with optical spatial positioning. Based on dual-helix point spread function, a 3D temperature optical measurement system with a resolution of 0.625 °C is established, providing a new perspective of 3D temperature measurement inside the cell. We thus offer an original research tool for further revealing the evolution process of secretions in cell metabolism.