The present invention relates to a method of drying biological and other labile samples so that they can be preserved as a highly viscous liquid. The method involves the steps of preparing a preservation sample by dissolving/suspending an active agent in a solution of a stabilizing agent, subjecting the preservation sample to such temperature and pressure conditions that the preservation sample loses solvent by evaporation without freezing or bubbling to form a foam and removing solvent until the preservation sample dries to form a highly viscous liquid.