An isoperibol calorimeter for the investigation of biochemical kinetics and isothermal titration calorimetry

Abstract

Isothermal titration calorimetry is a technique used to measure the enthalpy change associated with a molecular binding interaction. From these data, the binding constant for the reaction can be determined. In the scope of a larger project to design a high sensitivity instrument for collecting such data, the current methods in isothermal titration calorimetry were investigated. Further calorimetric experience was acquired by designing a large scale calorimetric device. Dilution reactions with dimethyl sulfoxide and water were conducted to measure the excess enthalpy of binding. The inaccuracy of these measurements necessitated the more careful design of an isoperibol calorimeter. This calorimeter was modeled was an arrangement of coupled thermal masses and capacitances in order to fully understand its transient response to a thermal input. Dilution reactions and a neutralization reaction with HCl and NH40H were performed on the system and the results were used to make recommendations for the design of the future high sensitivity device.