Hitachi CHROMASTER 5160 Instruction Manual page 763

3.4 Caution on Handling
3.4 Caution on Handling
(1) Caution on Solvent Replacement (substitution)
For solvent replacement, make sure the old and new
solvents will be dissolved in each other. If the old solvent
will not be dissolved in the new one to be used, first replace
the old solvent with an intermediary solvent which will be
dissolved in both the old and new solvents, and then
replace the intermediary solvent with the new one.
NOTE: For replacement of a salt-containing solvent with
an organic solvent, adequate replacement is
required with distilled water in order to prevent
clogging of the flow path due to the precipitation
of salt, and then replacement with the organic
solvent should be attempted. (For replacement
of an organic solvent with a salt-containing
solvent, adequate replacement with distilled water
is also required in the same way as above.)
The internal volume of the degassing chamber in
this degassing unit including tubes is about 5 mL
per flow path. For complete solvent
replacement, about 15 mL of solvent is required
for each flow path. And for solvent replacement
by use of the pump, a flow rate of 5 mL/min or
lower is required for preventing formation of
bubbles.
(2) Caution on Solvent Changeover
Although the solvent can be degassed adequately in the
degassing unit, the air is dissolved through Teflon in the
connecting tubes. Therefore, if the flow through one flow
path is stopped for a long time, degassing of the solvent in
the connecting tubes becomes inadequate.
An organic solvent, in general, changes its absorbance due
to degassing. Therefore, the baseline may be disturbed at
the time of flow path changeover.
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