HPLC of Detergents

[putnam]

Hi!

n-tetradecyl-B-D-maltopyranoside has very low UV absorbance. It has been suggested that I try RI detection, but I know this is problematic.

Also, it has been suggested that the analyte can bind irreversibly with a C18 column.

So, what method of detection is most suitable for a detergant such as this. Also, what columns and mobile phases should I be looking at?

Thank you,

Putnam

[Uwe Neue]

There is no reason that this compound will be "irreversibly" bound by a C18 column. You have an issue with the combination of hydrophobic tail and polar head, but this is not a fundamental problem.

I would take a good well endcapped C18, use UV at 210 nm and run a gradient from 50% MeCN/H2O to 100% MeCN. You should be able to find the peak.

An alternative and better detection method is ELSD, if you have this available. If you have this, I would consider using methanol instead of MeCN.

[Chris Pohl]

Putnam,

Dionex sells a good general-purpose column designed specifically for surfactant analysis. You can find more information about the column at this link ( http://www1.dionex.com/en-us/columns_ac ... 25924.html ), although you won't find anything specific about your analyte. It has been shown to be useful for wide variety of surfactant type so I'd be surprised if it didn't work for your surfactant as well. I agree with Uwe that ELSD is a good first choice for this type of work. You'll see at the link above that a good portion of the chromatography is done with this detector. If you're interested in having someone here take a look at the chromatography of n-tetradecyl-B-D-maltopyranoside on this column, please e-mail me directly.

[james little]

I did a lot of work on surfactants with mass spectrometry.

see

http://users.chartertn.net/slittle/