Cold storage of reagents, IVF, vaccines, living
cells and other biologics requires the use of an ultra low
temperature freezer. One type used is the mechanical ultra-low
temperature freezer. Another well-known type is the Dewar liquid
nitrogen freezer.
While blood bank/pharmacy freezers typically store
some pharmaceuticals and vaccines between 0 and -20 degrees C,
mechanical ULT freezer systems are meant for cold storage of
materials between -20 degrees C to -150 degrees C, and Dewar
cryogenic LN2 immersion freezers operate down to -196 degrees C.
A lesser used approach is a vapor phase Dewar freezer. This type
of system stores samples in the vapor region above the base
layer of liquid nitrogen at temperatures between -90 and -150
degrees C.
For example, whole blood is usually stored between
2 and 8 degrees in a more traditional freezer. Vaccines can be
stored in more traditional freezers down to -20 degrees C, but
some need to be stored at temperature down to -86 degrees C. For
extremely low temperature cold storage, some samples must be
first mixed with cryo-protective agents and slowly dropped in
temperature before attaining optimal cold storage to eliminate
ice crystal formation and to cease all cell function.
However, once vaccines and other biologic materials
are within their required cold storage temperature range, the
freezers chamber temperature must be continuously monitored and
maintained. Thus, a redundant cold storage backup system is
required - one that is independent of the main control and
monitoring system. If a multi-function backup system is not
used, then any of these critical materials may be at risk.
Fortunately, for mechanical ULT freezers, we
offer the CA5000-C
Liquid C02 Freezer Power Backup and C02 Backup Injection
System and our CA5000-N
Freezer Power Backup and LN2 Backup Injection System.
Both systems function as a backup monitoring system and will
work with ANY mechanical freezer. They include 24 to 48-hour
battery backup operation and can maintain desired internal
freezer chamber temperature in the event of a mechanical
failure, coolant loss, or power outage; thereby safeguarding
your precious biological materials.
CA5000-C Liquid CO2 Freezer Backup System
For Dewar cryogenic biologic cold storage
systems, we offer the Model
LD 215 LN2 level detector/alarm. This system is able
to accurately detect low liquid cryogen levels (by measuring
rising local temperatures due to LN2 evaporation) using a
specialized RTD probe positioned above the cryogenic liquid (see
below). The unit and probe includes audio and visual alarm
indication, an SPDT relay output, a rechargeable battery backup
system, user-programmable alarm status indication, an alarm
delay feature, and an alarm mute function.
LD-215 Liquid Nitrogen Level
Detector/Alarm