Operation Manual Shodex GPC HK-400 series Version 201210E
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eluent has low miscibility/solubility to the eluent of previous analysis, first use the eluent that is
miscible/soluble to both eluents, and then replace it with the desired eluent.
e.g. When replacing water to chloroform, first run methanol and then introduce chloroform.
Attention! • If the eluent left in the system is not compatible with the column to be used, it may
damage the column.
• A drastic change in the eluent compositions may remove substances adsorbed on
the system and they may enter and deteriorate the column.
6.2. Column Installation
(1) Connect the column to LC system by following the “flow direction arrow” () indicated on the
name tag. If guard column is used, position the guard column in front (before the inlet) of the analytical
column.
(2) Make sure to insert the tubing all the way to the end fitting and secure it with the male nut. It is
important that there is no extra space between the tubing and the column side of the end fitting.
Presence of an extra space will let the sample to spread out and may result in wide peaks.
(3) Set the initial flow rate at less than 0.3 mL/min and start the system. If using the column at an
elevated temperature, keep a low flow rate until the temperature of the column reaches to the set
temperature, and then gradually increase the flow rate to the desired.
(4) Multiple number of columns can be connected in series. When connecting multiple columns with
different exclusion limits, set the column with higher exclusion limit at the upper stream position.
When connecting HK-404L, use multiple number of the same columns in series. This is because HK-
404L is prepared by using several different gels with different pore sizes, designed to provide linear
calibration curves over a set molecular weight range. If a HK-404L was used together with columns
with different pore sizes, this changes the mixing ratio of the gels and consequently it may deform the
linear calibration curve.
Caution! • Verify that there is no solvent leak. It may cause electronic leakage, rust, and/or
chemical injury.
Attention! • Make sure not to let air bubbles enter the column while installing the column. The
air bubbles may damage the column.
• When restarting the system after column installation or after holding the eluent
flow, start the system at less than 0.3 mL/min. A rapid increase in pressure can damage
the column.
• If the column was used at an elevated temperature, lower the flow rate to less than
0.3 mL/min at the end of analysis. Then, turn off the column oven, and let the column
temperature return to room temperature before stopping the pump. If the pump was
stopped while the eluent inside the column was still hot, as the eluent temperature
decreases, its volume also decreases. This may result in creating an empty space in the
column and deteriorates the column.
Guard filter (HK-G): Installation
(1) At the first time use, connect the flow line to the guard filter inlet alone (do not connect to the
analytical column), set the flow rate at 0.3 mL/min and start the system. Leave it for about 1 minute.
(2) Stop the system and connect the outlet of the guard filter to the inlet of the analytical column,
tighten by hand. Place wrenches on the parts indicated by ★and tighten additional 30 to 60°. After