By Anonymous on Tuesday, June 29, 2004 - 11:14 pm:

Dear All,

My project is to analyze different surfactants, anionic, cationic, and nonionic ones, by HPLC method. Could anyone tell me what column(s) I can use for such application? Is there any column available just for surfactant analysis? If yes, please kindly tell me relating information.

Thanks a lot.

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By Alexander on Thursday, July 1, 2004 - 07:10 pm:

I don't know if this helps:

http://www.alltechweb.com/productinfo/t ... /A0033.pdf

First question: what kind of detection are you going to use? Can't use UV. Then think about the column an mobile phase.

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By Consumer Products Guy on Friday, July 2, 2004 - 07:53 am:

This is a very complicated topic, way too large for this space. We use a vast range of assays including HPLC, GC, wet methods. Can you narrow your focus?

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By Anonymous on Friday, July 2, 2004 - 08:00 am:

To Alexander,

Thanks for the response.

For dodecylbenzene sulfonate, I can use UV detector. But for alkyl sulfates or sulfonates, I guess I have to use conductivity detector or ELSD. Is "Alltech Surfactant/R" a specialty column for surfactant analysis?

To All,
Does anyone know what column I can use for nonaionic surfactant, such as Triton X-100 or Tween 20?

Thanks

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By Consumer Products Guy on Friday, July 2, 2004 - 08:14 am:

For octylphenol/nonylphenol ethoxylates like Triton-X 100, if you want one peak for quantitation you can use RP-18 with water-ACN and UV detection at 280nm. The peak will be a little broad due to being a mixture.

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By Anonymous on Friday, July 2, 2004 - 09:23 am:

To Consumer Products Guy,

To be specific, I am doing Triton X-100 analysis using a RP C18 column with UV detection (mobile phase: ACN/H2O=50/50). What I got is a broad peak. I am not sure if it is normal.

It would be great if you can share some information on what column I can use, method, and what result I should expect (broad peak or multiple fine peaks).

Thanks.

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By Anonymous on Friday, July 2, 2004 - 09:32 am:

Thanks, Consumer Products Guy.

You answered my question even before I asked it.

I am wondering if there is a column that prodives better resolution than C18 columns, showing all components in Triton X-100 (say at least 10 resolved peaks), or if better resolution is desirable in some cases .

Thanks

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By Anonymous on Tuesday, July 6, 2004 - 12:25 am:

For Triton X100, ELSD can be prefered, both sensitivity and peak shape are better.

Take a look also to Porous Graphitized Carbon Column (cf. Journal of Chromatography A, Volume 797, Issues 1-2, Pages 83-91)

I use hypercarb column with ELSD detection, it is fast and efficient separation

For detergents (surfactants), I found this http://www.sedere.com/chroma/app061.gif
on SEDERE Website (ELSD manufacturer)

Hope it helps!

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By Chris Pohl on Saturday, July 10, 2004 - 02:15 pm:

Anonymous (Friday, July 2 9 a.m.)

Indeed, it is normal to see a rather broad peak for Triton X-100 on a conventional C18 column as such a column has difficulty resolving compounds which vary only in the degree of ethoxylation. If you are interested in testing a column of the sort you requested, e-mail me directly.