Page 1 of 1

water sample injection on Hp-1 and HP-5 columns

Posted: Wed Jun 12, 2013 4:13 pm
by mmm83
Hi all

I know that water damage the non polar column like hp-1 and hp-5 and if we want to work with water we should be use column like carbowax and other but i search for this information on internet and i cant find any reference document mentioned that even agilent does not mention that so the question is this information is true or not ? and what the reference on that ?

Thanks

Re: water sample injection on Hp-1 and HP-5 columns

Posted: Wed Jun 12, 2013 5:43 pm
by rb6banjo
Here's what Agilent has to say about it.

http://www.chem.agilent.com/Library/ese ... ctions.pdf

I don't like to inject water just because it is not good for FID detectors (tends to extinguish them) and many times it is not a very good solvent for focusing analytes at the head of the column after injection. Other than the chromatographic issues, I don't think that you'll see a lot of extra wear and tear on your columns. Water lays down on a wax column better but I would still think that any of the concerns that Agilent mentions in the document above would apply for the wax as well.

I'd be sure to get it up to a pretty hot temperature before injecting another sample. I guess some type of headspace analysis (SPME, static, purge-and-trap, etc.) is not an option for you?

Re: water sample injection on Hp-1 and HP-5 columns

Posted: Wed Jun 12, 2013 9:01 pm
by chromatographer1
As long as the water is not allowed to condense to liquid form for long time periods there is usually no or little harm done to any phase of a column.

It is when water liquifies on the phase surface that focusing of the analytes becomes difficult, promoting the flat or tailing peak issues, and chemical reactions can occur which can damage the bonding of the phase to the surface of the tubing promoting the 'where did all this bleed come from' issue.

Keeping the column temperature above 100C would help to minimize the water damage from aqueous injections.

best wishes,

Rod