CombiFlash Torrent® User Manual - Isco

Section 3 Operation
3.2.1 Liquid Sample Injection
If the sample is soluble in the starting mobile phase, it can be
prepared as a solution and injected onto the column when
prompted during the purification run.
3.2.2 Solid Samples
Some compounds are not soluble in solvents that are
compatible with the chromatography. In addition, the
compounds may have very limited solubility in any solvent,
resulting in sample volumes that are impractical for good
chromatography. The answer in this case is solid sample
introduction. Here the reaction mixture or dissolved sample is
mixed with the same media in the chromatography column.
Some samples of this type may be simply dissolved and placed
into a prefilled cartridge. You can then use the cartridge
immediately or dry it before placing it on the system.
Other samples may need more care. Typically you would
create a mixture of 20% sample load to media (w/w). Then dry
the mixture under conditions that will drive off the solvent
without affecting the compounds of interest. These compounds
remain bound to the media. Once dried, pour the
media/sample mixture into an empty cartridge.
To prepare an empty solid sample cartridge:
1. Ensure the empty cartridge has a bottom frit.
CAUTION
Missing frits may cause equipment damage, UV detection
problems, or increased maintenance. Frits prevent solids from
entering the fluid path.
2. Prepare the media and sample:
a. Dissolve your sample in a minimal amount of a suitable,
volatile solvent.
b. Place the media into the solvent. If using silica gel, a
particle size of 40–60 µm (240–400 mesh) is
recommended. The amount of silica required is about
four to five times the mass of your sample.
3-5