A HIGH-SENSITIVITY TITRATION CALORIMETER USING PYROELECTRIC SENSOR

A new sensitive isothermal titration microcalorimeter using polyvinyli dene difluoride (PVDF) as detector has been developed. Heat pulses of less than 0.4 mu J can be detected and the baseline noise level (p-p) is 40 nW. The calorimeter is constructed with one reaction cell (0.7 m l) insulated by several radiation shields inside a vacuum chamber. The performance of the instrument was examined by measuring the heat of p rotonation of Tris with HCl. The enthalpy of reaction was found to be -49+/-1 kJ.mol(-1), in good agreement with the reported value of -47.5 kJ.mol(-1).