C18 SPE cartridges - variations
Posted: Wed Aug 26, 2009 8:30 pm
My collaborators recently bought 3 varieties of Bond Elut C18 cartridges:
HF BOND ELUT C18, 17.4% carbon loading, endcapped
BOND ELUT C18 INT, 12.2% carbon loading, endcapped
HF BOND ELUT C18 OH, 14.9% carbon loading, non-endcapped
What might be expected to be different between the first two, where the only difference is carbon loading?
I understand that for the non-endcapped variety, the SiOH groups would be expected to interact better with some polar compounds; but wouldn't those compounds wash off just as fast with the aqueous loading solvent, since water interacts with those groups too? Does this mean the C18 OH cartridges would only hold onto analytes that interact with SiOH much more strongly than water itself?
Discuss.
HF BOND ELUT C18, 17.4% carbon loading, endcapped
BOND ELUT C18 INT, 12.2% carbon loading, endcapped
HF BOND ELUT C18 OH, 14.9% carbon loading, non-endcapped
What might be expected to be different between the first two, where the only difference is carbon loading?
I understand that for the non-endcapped variety, the SiOH groups would be expected to interact better with some polar compounds; but wouldn't those compounds wash off just as fast with the aqueous loading solvent, since water interacts with those groups too? Does this mean the C18 OH cartridges would only hold onto analytes that interact with SiOH much more strongly than water itself?
Discuss.