Smaller means more sensitive.

The article presents information about nanothermometers. Old-fashioned spring thermometers are notoriously inaccurate. In the nanoscale version heat-sensitive springs composed of polyethylene glycol chains are attached at one end to a gold sphere 20 nanometres across. The nanothermometers are designed to be used with microfluidic devices. The cadmium telluride glows when struck by laser light--and the closer to the gold it is, the more brightly it glows. At low temperatures the springs are coiled tightly. They could be used to monitor enzymatic and blood reactions, which can be very sensitive to temperature changes.