Download Lyophilization, Concentration or Evaporation

Lyophilization, Concentration or Evaporation — Which is better for my Process?
Lyophilization, vacuum concentration and vortex evaporation have many similarities but
they are different processes, which lead to different outcomes. Deciding on what process
is best for your sample can be an intimidating task.
Lyophilization is used for multiple processes including
long-term storage and sample preparation.
Lyophilization dries the sample using sublimation —
the conversion of water from the solid state (ice)
directly to the gaseous state (water vapor) without
going through the liquid state. Three steps are required
in the lyophilization process: pre-freezing, primary
drying and secondary drying. Each step is important,
and needs to be complete for freeze drying to be
successful. The eutectic temperature, or freezing point,
of the sample must be known before starting the freeze
Above: FreeZone -105˚C Freeze Dry System
dry process. In order to freeze dry properly, the freeze
dry collector must be 15˚ – 20˚ Celsius colder than the
sample’s eutectic temperature. For example, water has a freezing point of 0° C. A freeze
dryer with a collector of -15° C to -20° C or lower is required. If the sample is
Acetonitrile, a -84˚C cascade freeze dryer is recommended. If the sample contains
alcohols a -105˚C freeze dryer is needed. During primary drying, 92-93% of the moisture
is removed from the sample. Labconco’s FreeZone® Freeze Dry Systems are available in
collector sizes from 1 liter to 18 liters. FreeZone Systems are available in benchtop and
console models and with collector temperatures of -50° C, -84° C and -105° C.
Freeze drying can be a lengthy process taking anywhere from 12 hours to a week.
Because of this, using a vacuum concentrator might be a better option.
Vacuum concentration is a sample preparation process using
centrifugal force, heat and vacuum to remove moisture from
a sample. Vacuum concentration dries the sample using
evaporation — the conversion of liquid to vapor. A cold trap
is used in line to protect the vacuum pump and capture the
solvent during the process. Vacuum concentrators take the
sample to 99% dryness in a relatively short amount of time
and can typically run any solvent regardless of freezing or
boiling point. Labconco offers a full range of CentriVap®
Vacuum Concentrators, including the exclusive Refrigerated
CentriVap for heat sensitive samples such as RNA or
proteins.
Above: Refrigerated CentriVap
Vacuum Concentrator
Vortex evaporation also removes liquid to concentrate a sample
for sample preparation. Unlike a vacuum concentrator, a vortex
evaporator uses vortex motion instead of centrifugal motion.
Because of the vortex motion, the analyte is washed down the
sidewalls of the glassware increasing the recovery of the
analytes being tested. Labconco offers two types of RapidVap®
Evaporation Systems: one uses vacuum and one uses nitrogen
blow down to speed evaporation. Sample sizes can be as small
as 1 ml up to 450 mls per sample tube.
Above: RapidVap Vacuum
Evaporation System
The Chart below will help with choosing the right process for your samples.
FreeZone
Micro liters to 6L
Micro plates, micro
centrifuge tubes, test
tubes, flasks, serum
bottles, bulk
12 hours – week
Freeze Dryer, drying
chamber, vacuum pump
CentriVap
Micro liters to 25mls
Micro plates, micro
centrifuge tubes, test
tubes
RapidVap
4.5mls – 450mls
Test tubes, 170 ml &
600 ml tubes
25 minutes to 6 hours
Concentrator, rotor,
pump
Accessories
Glassware, adapters
Pump type required
Rotary Vane,
Hybrid
Applications
Aqueous, protein,
peptide, vegetation,
environmental, HPLC,
Pharmaceutical
Cold Trap, CentriZap,
glassware, secondary
traps, additional rotors
Rotary Vane,
Diaphragm,
Hybrid
Peptides, DNA,
Proteins,
oligonucleotides,
pharmaceutical
25 minutes to 6 hours
Evaporator, Block,
pump for Vacuum
System, N2 regulator for
N2 system
Glassware, secondary
traps, racks, additional
blocks
Diaphragm
Sample Volume Range
Sample Tube Size
Processing Time Range
Components Required
Environmental, EPA,
toxicology, biological,
microbiology, food
chemistry,