Hitachi CHROMASTER 5160, Instruction Manual

Page: 342 / 1022

3.7 Preparatory Operation
(d) After confirming that no bubbles are discharged, turn
OFF the power switch of the ultrasonic washer.
(e) Take out the mobile phase container from the
ultrasonic washer and wipe off moisture adequately.
Then set the container in a liquid chromatograph.
(2) Example of Degassing by Decompression (when mobile
phase is an aqueous solution)
Example: Ethanol 20% + water 80%, aqueous solution of
0.2% citric acid
Necessary devices:
1) Ultrasonic washer
(Be sure to fill the bath with water.)
2) Aspirator having a rubber plug which matches the
mouth of the mobile phase container to be used.
Match rubber
plug with
container.
Mobile phase
container
Ultrasonic
washer
Aspirator
(a) In an ultrasonic washer, place the mobile phase
container after adequate stirring (see “*” below).
* For using a mixed mobile phase, complete mixing
by means of a stirrer is required. Otherwise, poor
reproducibility or baseline drift will be caused.
NOTE : The mobile phase of an aqueous solution must
always be degassed by using both an ultrasonic
washer containing water and decompression with
an aspirator. The time period of degassing
should be constant.
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