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10 TIPS to MAXIMIZE
the PERFORMANCE of YOUR SPEEDVAC SYSTEM
TRY A LITTLE
HEAT
If your samples aren't drying fast enough in
the SpeedVac try a little heat for faster solvent evaporation. Start the
run with a pre-warmed chamber and set the chamber heat at 50°C. As long
as there is solvent in the tube and it is evaporating, the sample will
be cool (below ambient temperature). Be ready however, to stop the run
and remove the sample when it is dry.
EMPTY TO COLD TRAP
Start every SpeedVac run with a clean empty glass condensation flask
in the cold trap. This will result in more efficient trapping of solvent
vapors by providing more surface area for condensation and help to
protect the vacuum pump.
FILTER THE OIL
If you are drying down samples that are in acid, it is a good idea
to put a VPOF110 on the High Vacuum Oil Pump. The VPOF110 circulates the
pump oil through an activated alumina cartridge which removes the acid
from the oil to prolong the life of the pump and reduce the frequency of
oil changes.
TRY A COLD TRAP WITH A
DRAIN
The ModulyoD condenser that is used in freeze drying systems
operates at -50°C and has a drain. It also has an accessory that will
allow a SpeedVac Concentrator to be connected to the unit. This setup
can be used when evaporating organic solvents that don't freeze and need
to be removed from the trap after every run. It simplifies trap cleaning
and maintenance. Open the drain, collect the solvent in a waste
container, and get ready to start the next run.
TRY A SECONDARY TRAP
The Cold Trap is the primary trap on a vacuum drying system and
should condense and trap 85 to 95% of the solvent vapors coming from
your samples. Sometimes a Chemical Trap is needed as a secondary trap to
"polish" the air. Cartridges with activated carbon will adsorb organic
solvent vapors and volatile radioactivity. Cartridges with soda lime
will neutralize acid.
CHECK THE LEVEL OF
CRYOCOOL
The CryoCool heat transfer fluid must be at the proper level for the
trap to operate efficiently and make it easy to remove the glass
condensation flask to empty the trapped solvents. The CryoCool should
come up to the shoulder of the GCF when it is pushed down into the
stainless steel pot of the cold trap.
KNOW THE EFFICIENCY OF
YOUR COLD TRAP
If you are evaporating organic solvents in your SpeedVac System, it
is good to know the efficiency of the Cold Trap. Start the run with a
clean, empty Glass Condensation Flask in the Cold Trap. After the run is
over and the samples are dry, remove the GCF and allow the contents to
thaw. Pour the solvent into a graduated cylinder and measure what has
been collected. Divide that number by the total started with and
multiple by 100 for the percentage of solvent trapped. It should be 85
to 95%.
MAKE SURE YOUR
SPEEDVAC CONCENTRATOR IS GETTING ENOUGH VACUUM
A vacuum gauge will tell you if the vacuum level is good enough for
evaporating your solvents and drying samples in a reasonable time. Since
the gauge also measures solvent pressure it can be used as a guide for
applying heat to the samples in the concentrator. The vacuum gauge can
also indicate the condition of your vacuum pump.
INCREASE YOUR SOLVENT
TRAPPING EFFICIENCY
Trapping the solvent prevents contamination of the vacuum pump.
Using a colder trap (RVT4104 @ -104°C) or connecting two traps in series
(RVT400 + RVT4104) is a good way to condense and trap more organic
solvent vapors to protect high vacuum pumps.
CHANGE YOUR SAMPLE
PROTOCOL
Try using larger glass tubes or vials for your samples to provide
more surface area and better heat conduction. Try using an aluminum
rotor block to conduct heat more efficiently. Use a radiant cover to
apply more heat to the sample tubes. Evaporative cooling will keep the
samples at sub-ambient temperature while the solvent is evaporating.
When the solvent is gone and the samples are dry, they will heat up so
be ready to stop a run and take the samples out.
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