Shutting Down The 2410 Refractometer - Waters 2410 Operator's Manual

When you change solvents, be aware that:
• Changes involving two miscible solvents may be made directly. Changes involving two
solvents that are not totally miscible (for example, from chloroform to water), require an
intermediate solvent (such as isopropanol).
• Temperature affects solvent miscibility. If you are running a high-temperature application,
consider the effect of the higher temperature on solvent solubility.
• Buffers dissolved in water may precipitate when mixed with organic solvents.
When you switch from a strong buffer to an organic solvent, flush the buffer out of the system with
distilled water before you add the organic solvent.
To change solvents:
1. Make sure the 2410 refractometer Purge Out line goes to waste.
2. To prevent backpressure in the column, replace the column with a union.
3. Set the pump or solvent delivery system flow rate to 5 mL/min.
4. Press 2nd Func, then Purge.
5. Let the 2410 refractometer purge for a minimum of 5 minutes.
6. Press 2nd Func, then Purge to stop purging.
7. Follow steps 1 through 5 to purge the 2410 refractometer with 10 percent
methanol-water before storing it.

5.4 Shutting Down the 2410 Refractometer

Note: Do not power off the 2410 refractometer unless you are storing it.
If you are not storing the 2410 refractometer, set the flow rate to 0.1 mL/min and keep the pump or
solvent delivery system operating. This minimizes the amount of time the 2410 refractometer needs
for reequilibration when you use it again.
Do not leave buffers in the system after use. Flush the lines first with HPLC-grade water and then
with a suitable solvent (Waters recommends HPLC-grade methanol).
Attention If your storage solvent is incompatible with your column, remove the column
STOP
before flushing.
Power off peripheral devices before shutting down the 2410 refractometer. To power off the 2410
refractometer, press the ON/OFF switch located at the lower right front corner of the unit.

Shutting Down the 2410 Refractometer 5-15

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