BEH amide UPLC column question

Do these columns typically operate at higher than normal pressures? I have a 2.1 X 100 column and at low organic concentrations the backpressure is awfully high (~5000 psi at 0.2 ml/min, 15% CH3CN)) even for UPLC. At 0.4 mL/min, where we typically run other columns, it was pushing 9K before I terminated the flow. We usually dont see above 7K with other column chemistries. At higher acetonitrile concentrations the pressure seems similar to our other UPLC columns. Thanks

Answers

  • The BEH Amide column was designed for HILIC separations that use high concentrations of ACN. As is described in the BEH Columns Care & Use Guide (see pages 5 & 10 in link and attached), if you operate at aqueous concentrations greater than 60%, you will see higher than expected backpressures. This is normal and expected.

    May I ask why you are trying to use this column with such a strong HILIC mobile phase (85% aqueous)? In our experience, most HILIC separations require no more than 40% aqueous mobile phases to elute all analytes. If you do require highly aqueous mobile phases (e.g., Glycans), you must reduce your flow rate accordingly.

    Good luck,

    --Doug

  • Thanks. I really suggest Waters make it easier to find this type of material.

  • Hello,

    All of this type of information is posted on the overview tab under UPLC Basics - Care and Use Manuals.

    We've pretty much taken all UPLC related information and segmented it out on the Overview Tab in the community - so it's more than a community - it's also a portal of UPLC information.

    I hope you'll find this to be helpful in your work.

  • That is fine. But it should also, IMO, be linked directly from the Acquity BEH Amide column page on the Waters website.

    http://www.waters.com/waters/nav.htm?cid=513206

    Under the "literature" tab, every other imaginable piece of semi-related literature is linked under said page somewhere, but I could not find the info that Doug linked.

    Additionally, it should be plainly linked here:

    http://www.waters.com/waters/partDetail.htm?partNumber=186004801

    but I dont see it there either.

    Thank you for the help and again, I apologize if I am the only one that is having difficulty with this.

  • We will certainly take your comments into consideration.

    Recently, additional information [including application highlights] were posted to the Waters website demonstrating the intended use of the ACQUITY UPLC BEH Amide column for Hydrophilic interaction chromatography.

    http://www.waters.com/waters/keywordSearch.htm?cid=505548&qTemp=amide&q=amide&filter=searchcontenttype|APNT

    Additionally, example applications are demonstrated on the ACQUITY UPLC Columns brand page under the details tab, highlighting its utility for HILIC as well as carbohydrate analysis (which is conducted under HILIC conditions).

    http://www.waters.com/waters/nav.htm?cid=513206#

    We are in the process of adding additional application highlights for carbohydrate analysis as well.

  • Hi,

    Maybe i missed it in the product literature, but what is the recomended operational Temperture range of the BEH Amide column?

    thanks

  • Temperature limit is 90 C for beh amide , but at higher pH (>7.5) dont exceed above 60C for long lifetime of column, but i read in Waters research papers beh amide is highly stable at high temp. & high pH ... i think recommended range to start a method is from 40-60C for beh amide...

    ~ Salman

  • great,

    that is what i hoped based upon the other BEH products but i have been playing it safe at 40C

  • Frankly, there is no need to 'play it safe' by operating at 40oC if the reason you are doing is fear of shortened column lifetimes. The BEH Amide chemistry (unlike older silica-based amino columns) is an extremely rugged HILIC chemistry. You can used the BEH Amide column at whatever temperature that you wish in order to get the desired separation.

    Operating limits are in the ACQUITY UPLC Columns Care & Use Instructions (715001371). In the Care & Use instructions 'Getting Started' section there are some suggested conditions that can get you started.

    Basically, think of it this way: the maximum operating temperature for the BEH Amide column is that of your ACQUITY UPLC Column Oven/Manager. I've attached a couple proof statements that were generated at Waters during the BEH Amide development project that demonstrate the ruggedness of this UPLC HILIC column chemistry.

    What type of application are you working on?

    --Doug

  • Hello,

    You can also find Care and Use manuals for these columns by gong to the community Overview Tab.

    Look in the right column under UPLC Basics - Care and Use Manuals. All ACQUITY UPLC related Care and Use

    Manuals will come up.

  • thanks for the directions to the new care and use procedures etc. I had an older version without the amide column and i had been looking in the latest online catalog which does not contain this temperature info.

    anyway my appplication is small basic molecules. I run a gradient and have acheived good retention and resolution of my 10+ analytes at 65C. All peaks have nice symmetry except the two most highly retained analytes which i will try to improve.

Sign In or Register to comment.