SAX switching from novosep A-1 anion to SphereClone SAX
Posted: Thu Mar 17, 2011 7:25 pm
Hi,
I recently developed a method in which I achieved resolution for a molecule which I was hoping to isolate for spectral analysis. The method was on a novosep A-1 anion 150X4.6 mm column from alltech using 90% water and 10% [25mM HCl/NH3].
Today I tried the same method on a SphereClone SAX 250X4.6 from phenomenex and I expected everything to be slightly better but it was all worse. I tried 0 - 50% [25mM HCl/NH3] and all gave no resolution for any peak.
Is the Alltech column simply superior or is the chemistry of the two different. I thought they were both quaternary alkyl ammonium columns.
The sample is the same, so is flow rate and temperature (50C) and all mobile phases are prepared fresh daily from the same bottles.
I recently developed a method in which I achieved resolution for a molecule which I was hoping to isolate for spectral analysis. The method was on a novosep A-1 anion 150X4.6 mm column from alltech using 90% water and 10% [25mM HCl/NH3].
Today I tried the same method on a SphereClone SAX 250X4.6 from phenomenex and I expected everything to be slightly better but it was all worse. I tried 0 - 50% [25mM HCl/NH3] and all gave no resolution for any peak.
Is the Alltech column simply superior or is the chemistry of the two different. I thought they were both quaternary alkyl ammonium columns.
The sample is the same, so is flow rate and temperature (50C) and all mobile phases are prepared fresh daily from the same bottles.