title: The cryopreservation of standard sera.
abstract: To determine the storage temperature needed for the preservation of standard sera for serodiagnostic tests, groups of sera were tested before and after storage at -70 degrees C and -20 degrees C for periods of up to five years. The temperature required depended on the nature of the test, but no definite advantage was found in storage at -70 degrees C. For complement fixation this temperature was inadequate and greatly inferior to liquid nitrogen. For immunofluorescence it had no apparent advantage over a temperature of -20 degrees C, and for some other tests it was no more than marginally superior.
mesh_terms: D001793:Blood Preservation / Q000379:methods*; D003168:Complement Fixation Tests; D003378:Counterimmunoelectrophoresis; D005455:Fluorescent Antibody Technique; D005615:Freezing; D006801:Humans; D011233:Precipitin Tests; D012015:Reference Standards; D012698:Serologic Tests / Q000592:standards*; D013696:Temperature; D013997:Time Factors