An Improved Procedure and Apparatus for Preservation of Sera, Microörganisms and Other Substances—The Cryochem-Process

Abstract

A process and models of apparatus are described which provide for the preservation of biologics by desiccation in vacuo from the frozen state at greater convenience and lower cost of operation than heretofore. Water-vapor is removed by a specially prepared calcium sulfate which may be regenerated by heat at atmospheric pressure. Procedures for the desiccation of various types of substances are described.