Changing Eluents 43
• Changes involving two miscible eluents can be made immediately, without an
intermediate eluent.
• To prevent eluent contamination, use the same container to prepare, supply, and
store an eluent. Once a container is used for one eluent, it should not be used for any
other eluent without a thorough cleansing.
• Consider the column chemistry. If the column will be damaged by the intermediate
or new eluent, remove the column from the flow path by performing one of the
following actions:
– Opening the reference valve
– Connecting the pump outlet tube to the detector inlet tube with a union.
Note: If you are changing to a miscible eluent, follow the procedure in Section 3.6.1,
Adding Fresh Eluent.
Flushing with an Intermediate Eluent
This section describes the procedure for flushing with an intermediate eluent.
Choosing an intermediate Eluent
To choose an intermediate eluent, use the following guidelines:
• When changing between organic eluents and buffered solutions, use water or a
predominantly aqueous eluent to prevent buffer salts from precipitating.
• When changing between immiscible eluents, use an appropriate intermediate eluent
that is freely miscible in both eluents (see Appendix B, Eluent Considerations, for
more information).
Flushing
Procedure
1. Filter and sparge the fresh intermediate eluent. See Section 3.1, Sparging Eluents.
2. Confirm that the vent lines are properly routed to an exhaust hood. See Appendix B,
Eluent Considerations, and Section 3.1, Sparging Eluents, for more information.
Caution: Do not use vacuum to degas eluents contained in the 1-gallon
brown bottles. Transfer eluents from these bottles to clean vacuum-safe
reservoirs for degassing.
To Next Page
Loading...
