How does the Dilution tab on the Sample Manager FTN work? - WKB67492

ENVIRONMENT

• ACQUITY UPLC H-Class
• ACQUITY UPLC I-Class
• ACQUITY Arc

ANSWER

You can dilute previously dissolved samples using the purge solvent as the diluent. For pre-injection sample dilution, create a sample dilution method, and then specify the method for the sample.

When you use the method to dilute a sample, these events occur:

• A specified volume of purge solvent is dispensed into the sample vial.
• If you specify a post-dilution delay, the system pauses to allow the sample and diluent to mix.
• The system aspirates the diluted sample from the sample vial and injects it.

ADDITIONAL INFORMATION

• Use only previously dissolved samples, without particulates or solids.
• Avoid nonvolatile or salt buffers as purge solvents.
• Ensure that the solvent is similar or identical to your isocratic or initial gradient solvent conditions, excluding buffers.
• Match the solvent to the sample diluent.
• Ensure that purge solvent and sample solutions or buffers are miscible and soluble.

 

To create a sample auto-dilution method:

1. In the instrument method editor, select the sample manager.

2. Click the Dilution tab > Enable.

3. If necessary, adjust the needle's placement (distance from the bottom of the vial or well when expelling diluent).

4. If necessary, in the Dispensed Purge Solvent box, specify the dilution volume in µL (default: 0 µL).

If necessary, in the Post-Dilution Delay box, specify a delay, in seconds, after the system adds the solvent (default: 0 sec).

6. Click Save.

 

The FTN overview and maintenance guide, in various sections, provides more information on the auto-dilution function:

• When auto-dilution is used, the purge solvent is used as the diluent. (Section 2.12)
• Auto-Dilution attempts to add a fluid to a sample already resident in a vial. (Section 2.12)
• The precision of the composite is almost entirely dependent on how well, and at what rate, the two fluids incorporate into each other. (Section 2.14)
• Some other information for users to consider (Section 2.37):
  • The Needle Height setting for depositing of dilution/purge solvent.
  • Choose a dilution/purge solvent volume large enough to dilute/influence the volume of sample in the vial.
  • Allow enough time for the Post Dilution Delay to accommodate static mixing.