Chromatography Forum

I was told by my colleague that an application chemist told her Hypercarb columns can only be used for cyanuric acid analysis and not melamine analysis.

Does anyone know why that is so? According to my understand of the retention mechanism, it should be ok, since melamine at pH lower than its pKa is positively charged and will lead to induced dipole on the graphite surface. Am I missing something?

I have tried the hypercarb columns for other analytes.
It is an interesting option but i think it may be replaced with a HILIC column in many cases.

Sometimes the hypercarb works well with a compound, sometimes it does not.
I have seen many compounds injected onto this column never to elute ever again. But for other compounds it can work miracles.

It also depends on what you are injecting, not just the analyte but what else is present in the sample that can negatively affect a good column.

I'd also look into the cleaning procedure for this column, as I said, it can retain some compounds very strongly. It is not silica so the process may be quite different. I can't say, it has been a while since I used a hypercarb.


Alp

I can recommend you publication of colleagues from my department:
DETERMINATION OF MELAMINE IN FEED BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY COUPLED MASS SPECTROMETRY
TOMASZ ŚNIEGOCKI, BARTOSZ SELL, ANDRZEJ POSYNIAK, AND JAN ŻMUDZKI
Bull Vet Inst Pulawy 54, 543-547, 2010

You can download it free: http://bulletin.piwet.pulawy.pl/images/ ... 543548.pdf

Authors used Hypercarb column to determination of melamine in feed, but they routinely use it with other matrixes.
On the other hand I use this column for corticosteroids analysis. Proper washing is crucial. Manufacturer (Thermo) recommends long washing set with acetonitrile (overnight). Other feature of this sorbent is thermal stability - you can use high temperatures like 60-80C and higher. Such high temperatures can be also used in the washing step.

Hi Alp, thank you for your comments and advice! I will definitely look into the cleaning procedures.

Hi dr_Pyrex, thank you so much for the reference!