Potential applications of microcalorimetry for the study of physical processes in pharmaceuticals

In calorimetry, the heat-flow to or from a sample is measured as a function of time (isothermal calorimetry) or temperature (scanning calorimetry). Th e technique is not dependent on the physical form of the sample and is usua lly non-destructive (exceptions include temperature-induced irreversible ph ase transitions and thermal decomposition). The inherent sensitivity of mod em instruments allows measurements on the micro-Watt scale. Calorimetry is highly suited to the study of pharmaceutical systems because small sample m asses are usually required and the technique is very sensitive to changes i nduced by, for instance, formulation or processing. It is the purpose of th is review to show applications of both isothermal and scanning calorimetry in the field of physical and bio-physical pharmacy. Potential applications include studies of physical stability, excipient compatibility, chemical st ability and the study of the potential interactions of and between macromol ecules such as lipids, surfactants, and nucleic acids, (C) 2001 Elsevier Sc ience B.V. All rights reserved.