Current Pharmaceutical Biotechnology - Volume 6, Issue 3, 2005

Calorimetric experiments on complex biological systems have been conducted since the 18th century. Lavoisier and Laplace developed an ice calorimeter to study the metabolism of a guinea pig through weighing the ice melted over the observation period and knowledge of the latent enthalpy of fusion of water. This early experiment set the scene for a number of other researchers but limitations in instrument design r Read More

The assessment of stability (of actives, excipients and/or formulated products) is an important, and often timeconsuming, part of pharmaceutical product development. Conventionally, HPLC is used to quantify the concentrations of a parent compound and any degradation products as a function of storage time. HPLC, however, is relatively insensitive to small changes in concentration and it is often the case that stability a Read More

A great number of pharmaceutical substances exist in crystalline solid-state. Because of the complexity of their chemical structure many different polymorphs of a given substance can exist. Polymorphic forms of solid pharmaceuticals influence not only their dissolution behavior, i.e. bioavailability but also their solid-state stability. It is well known that only one polymorphic form is thermodynamically stable and all other Read More

Isothermal calorimetry is rapidly becoming an indispensable tool for the quantitative determination of a variety of kinetic and thermodynamic parameters for a wide range of systems. In particular calorimetry is finding increased application to the investigation of stability and incompatibility of pharmaceutical materials. In order to draw meaningful conclusions and to predict behaviour in related systems it is necessary to hav Read More

In solution calorimetry the heat of solution (ΔsolH) is recorded as a solute (usually a solid) dissolves in an excess of solvent. Such measurements are valuable during all the phases of pharmaceutical formulation and the number of applications of the technique is growing. For instance, solution calorimetry is extremely useful during preformulation for the detection and quantification of polymorphs, degrees of crystallinity and pe Read More

Many features of microorganisms make them pre-eminently suitable for study by microcalorimetry. They have thus, in the past, been the basis of fundamental studies in metabolism and cellular physiology. In this review we look at the application of calorimetry to the impact of bacteria and fungi on the pharmaceutical industry both in the exploitation of useful microorganisms and the fight against harmful ones. Obviously the Read More

A key challenge facing the pharmaceutical industry is the production of biotechnological drug products such as proteins in a stable form. Freeze-drying is preferred for manufacturing such products because of the low temperatures used. However, the protein may still degrade during the process necessitating the inclusion of a protectant. This review describes the range of thermal analysis techniques that have been used Read More