Normal-phase UHPLC columns?

[jusuom]

We have several methods utilizing hexane-based normal-phase LC. Which companies provide normal-phase UHPLC columns?

[unmgvar]

I would much more look into your equipment possibility to stand working with hexane

UHPLC system with their new consumables are generally less resistant to work with hexane
see if the pump seals rotor seals and other consumables do not need to be replaced.
see also if other settings need to be changed like for the pumps of agilent, they have a special setting for different solvents that help for compression and baseline noise.
I know sepax does a Si and other NP phases
you will find far more HILICs in sub2 and vendors will tell you to switch the application for various reasons and many of them are quite good, like not working with hexane
and also because of the instrument possibility to handle hexane

[jusuom]

Thank you. I know that at least Waters has a hexane compatibilityk kit for Acquity. We just purchased Nexera UPHLC, and Shimadzu people said it can pump hexane. I hold them accountable for their words . Let them change seals and other consumables on their own account if the system does not pump hexane...

I will check Sepax website.

[jusuom]

Anybody know any other manufacturers of normal phase UPHLC columns??

[KDF]

You might try looking at SFC columns. These are all normal phase. Phenomenex sells a 1.8 um HILIC superficially porous column. ES Industries sells some of the ethyl pyridine and pyridyl amide versions. I have not tried these columns yet.

You might try looking into converting to SFC for your hexane based methods. You will be amazed.

[adam]

By the way with normal phase you don't really need UPLC systems, or columns that are designed to handle very high pressures.

The viscosity, and backpressure, are much lower with those mobile phases. So you can use something like a 1.8 um column and you will be well within the pressure range of "regular" HPLC.

[manzi]

Thank you. I know that at least Waters has a hexane compatibilityk kit for Acquity. We just purchased Nexera UPHLC, and Shimadzu people said it can pump hexane. I hold them accountable for their words . Let them change seals and other consumables on their own account if the system does not pump hexane...

I will check Sepax website.

Hello! I'm going to buy Nexera with Fluo and DAD and hexane is my "favourite" solvent.
What about your experience with Shimadzu? Do you have any tips ?
Thank you in advance and excuse my incorrect English (I'm Italian!)
Pamela

[jusuom]

Our Nexera will be installed in late Augusta. I got the following document:
http://users.utu.fi/jusuom/Nexera_and_hexane.pdf

Sot it is worthwhile to set the compressability factor accordingly when working at higher pressures.

[hollebekkers]

Shimadzu also provides XR-SIL columns. It’s a 2.2um sized particle normal phase columns for fast separations

[KDF]

Yes, use compressibility compensation. Hexane is one of the most compressible organic solvents [150 x10^-6/bar]
At 100 bar it compresses 1.5% before it starts delivering liquid. At 400 bar the pump will compensate 6% for each stroke, but I am not certain the compressibility is this linear.
Failure to compensate means lower actual hexane volumetric flow and a noisier baseline.