Hi,

It could be caused due to particle size differences of the columns. Amide backbone is the appropriate one for carbonhydrate seperation, shiff base formations and anomer mutorotations are not a problem for HILIC applications which could be occured as rt shifting and peak splitting at amine bacboned columns. But certainly the particle size matters and you are comparing the superficially porous particle (SPP) column ( Accucore-150-Amide-HILIC ) and sub 2um UPLC column (Acquity BEH Amide (100mm x 2.1, 1.7 um)).

If the other physical parameters are the same, I mean the ID and lenght than you may consider the eddy diffusion effect (van deemter equation) that cause band broadening and resulting coelution of oligosaccharides. This effect is minimised at UPLC columns. RT shifting not an abnormal symptom due to column back pressure differences between UPLC and SPP particle column applications but the resolution depends diverse of physical properties (ID, lenght, particle size, silica structures, qualities, porosities (this could be brand depended, e.g. Waters ethylene hybride and accucore particles are not at very similar particle characteristics)).

If there is not any way to change your column than you may modify your method like adding TEA (triethylamine) to get more succesfull resolutions by thinking into the consideration of pH limitations.

Emir.

Hi,

It could be caused due to particle size differences of the columns. Amide backbone is the appropriate one for carbonhydrate seperation, shiff base formations and anomer mutorotations are not a problem for HILIC applications which could be occured as rt shifting and peak splitting at amine bacboned columns. But certainly the particle size matters and you are comparing the superficially porous particle (SPP) column ( Accucore-150-Amide-HILIC ) and sub 2um UPLC column (Acquity BEH Amide (100mm x 2.1, 1.7 um)).

If the other physical parameters are the same, I mean the ID and lenght than you may consider the eddy diffusion effect (van deemter equation) that cause band broadening and resulting coelution of oligosaccharides. This effect is minimised at UPLC columns. RT shifting not an abnormal symptom due to column back pressure differences between UPLC and SPP particle column applications but the resolution depends diverse of physical properties (ID, lenght, particle size, silica structures, qualities, porosities (this could be brand depended, e.g. Waters ethylene hybride and accucore particles are not at very similar particle characteristics)).

If there is not any way to change your column than you may modify your method like adding TEA (triethylamine) to get more succesfull resolutions by thinking into the consideration of pH limitations.

Emir.

At the moment in my lab there is no TEA, but one time i get it i will try!

Thank you so much!

Those are two completely different HPLC columns. Those new to HPLC may not know that "columns" are all different. Not just the dimensions, particle size, but also the support used are different. Have you heard the expression, "you are comparing apples to oranges". In liquid chromatography no columns are truly equivalent. However, just use the papers as a guide and develop your own method to retain and resolve the compound. If possible, buy and use "identical" columns (note, no columns are actually identical, but they will get you close). If not, use columns with the same chemistry, then scale up or down in mobile phase composition and flow rate to accomodate your own HPLC system's requirements. Perhaps most importantly of all, please have someone local to you who has professional experience in using the HPLC system and understands the basics of method development assist you with your project. Learning just the basics of HPLC takes many years.