Question about acids and bases when doing HPLC

[Incitor]

Hello all,

I'm trying to figure out how to run two different samples: one contains 32% HCl and the analyte is fructose and the other contains a lot of sodium carbonate and the analyte is an NHC catalyst.

I have a C18 column, an NH2 column, a bare silica column, and a prevail carbohydrate column, which is al/nh2 stationary phase.

My question is this: can I just dilute and shoot these samples or do I need to remove the acid/bases?

[tom jupille]

For the fructose, a better choice might be a polystyrene column in the H+ form. Check with someone like BioRad for applications on "HPX87H".

For the catalyst, if you canget retention on the C18, dilute & shoot should work OK.

[carls]

You could use the prevail or other amino column (both silica based) for fructose but you will have to neutralize the acid. Injecting samples this acidic (even with 100x dilution with water) will likely slowly strip ligands from the sorbent. Interstingly even the organic polymer based column that Tom mentions above has a lower pH limit of ~1 per the manufacturer. You could use an amino SPE cartridge after neutralization to remove salts and reconcentrate the analytes.