Thermal microscopy of single biological cells.

Techniques that can probe the thermal properties of cells are used in many applications ranging from cryogenic preservation to hyperthermia therapy, and provide powerful tools to investigate diseased conditions. The structural complexity of cells, however, requires innovative modalities operating at a subcell scale. We developed a label-free, non-ionizing technique based on a thermoelastic lens. With this device, we captured images of single cells with a ~2 μm resolution based on thermal properties as the contrast mechanism. To investigate the thermorheological behaviour of cells, we present simultaneous acoustic imaging using an inverted opto-acoustic microscope. Acoustic impedances extracted from the acoustic images support the effusivity obtained from the thermal images. This technique should provide diagnostic tools at the single cell scale. [ABSTRACT FROM AUTHOR]