Abstract: A system and method for an improved calorimeter for determining thermodynamic properties of biological and chemical reactions. A microcalorimeter device comprises a thin amorphous membrane anchored to a frame. Thermometers and heaters are placed on one side of a thermal conduction layer mounted on the central portion of the membrane. An environmental chamber is vacated and humidified. First and second samples are placed on the membranes of first and second microcalorimeters. Each sample is heated and its individual heat capacity determined. The samples are then mixed by sandwiching the two microcalorimeters together to cause a binding reaction to occur. The enthalpy of binding is determined by measuring the amount of heat liberated during the reaction. The mixture is then heated and the heat capacity of the mixture is determined. From this data, a binding constant is calculated.