Abstract

Thermal denaturation can be described by a rate process, with an exponential dependence of the rate constant on the temperature. Most rate constants were measured with a time resolution in the range of seconds. A temperature- jump experiment which can measure on a faster time scale was developed.

The set-up allows to heat a volume of 70 nanoliters within 300 microseconds by the absorption of pulsed infrared radiation. Temperatures of up to 373 Kelvin can be reached. The denaturation of biomolecules in solution can be measured time resolved by absorption changes.

The set-up was tested measuring the denaturation of the protein chymotrypsin. For this protein an Arrhenius-like behavior of the denaturation rate was observed up to the time resolution of the experiment.

© 1998 Optical Society of America