MEMS_DSC: a new device for microcalorimetric analysis in the biological field

The metabolism of cells is studied by scientists using a number of cells high enough to have a signal in the regular differential scanning calorimetry (DSC). Currently the number of cells necessary for thermal analysis is on the order of hundreds of thousands. The cell metabolism researchers have been trying to reduce this number with an eye on the final prize of sample size of one. In this paper, we report a novel MEMS_DSC (Micro Electro Mechanical System-Differential Scanning Calorimetry), which reduces the number of cells needed for analysis by about two orders of magnitude. It uses the Seebeck effect generated by a polysilicon n-gold junction to convert the temperature measured from cells directly into a voltage signal. To characterize the device a laser was used to heat the sensor; a lock-in amplifier, coupled with an optical chopper, allowed us to measure a very low heat power (25.5 nW).