Pre-freezing samples, Adding sample – Labconco FreeZone 6 Liter Benchtop Freeze Dry Systems 77520 Series User Manual
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Chapter 4: Using Your Freeze Dryer
Product Service: Domestic 1-800-522-7658, International 816-333-8811
Some guidelines for setting the Freeze Dryer are shown below.
These show pre-freezing temperatures and vacuum levels. Exact
protocols must be determined by the user for the specific samples
that are being freeze dried.
Material
Solidification/Eutectic
Temperature
Pre-Freeze
Temperatures
Vacuum Set Point
Bacteria,Virus
-40°C and Colder
-50°C &
Colder
0.040 mBar &
Lower
Milk
-5 to -13
-15 to -23
1.65 to 0.77
Fungi
-40 and Colder
-50 & Colder
0.04 and lower
Vegetable Tissue
-25 to -50
-35 to -60
0.22 to 0.01
Human Tissue
-30 to –40
-40 to –50
0.12 to 0.04
Blood Plasma
-10 to –25
-20 to –35
1.03 to 0.22
Vaccine -30
to
–40
-40
to –50
0.12 to 0.04
Pre-Freezing Samples
Appropriate containers for freeze drying include ampules, serum
bottles, and wide mouth freeze drying flasks. Shell freezing of
samples is recommended for wide mouth freeze drying flasks.
Smaller samples in ampules and serum bottles may be frozen in a
freezer. The sample container size should always be at least two to
three times the sample size (i.e., 40 ml samples should be prepared
in 80 ml containers or larger). The temperature required for pre-
freezing is dependent on the characteristics of the sample. Pre-
freezing temperature typically is at least 10° to 20°C below the
eutectic or collapse temperature of the sample.
Adding Sample
The following procedure should be followed when using sample
valves in the freeze dry process:
1. Connect a pre-frozen sample to a sample valve on the drying chamber
or manifold using an adapter. Turn the plastic valve knob to the
“VACUUM” position to open the valve. The bevel on the knob
should be positioned toward the sample port to apply vacuum to the
sample.