Abstract
The application of rapid-freezing techniques to differential scanning calorimetry (DSC) provides a new approach for understanding the organization of lipids in biomembranes. Use of quick-freeze DSC on membranes of mixed lipid composition supports the existence of nonrandom distributions of lipids (domains) in fluid bilayers. In addition to allowing investigations on the organization of lipids in fluid bilayers, the quick-freeze technique now allows calorimetric studies to be carried out on mammalian membranes which, because of their high cholesterol content, have not been previously amenable to study by DSC.