Chromatography Forum

Hi,

I have been asked to look into a quantitation method for polysorbate 20 in one of our products.

There are a lot of different methods described in litterature, all claiming to be better than the others

Would be nice to hear if anyone of you have a preference for what to use.
First decision is if we should get a ELSD or a CAD detector. UV seems to be out of the question regardless of method.

We did use HPLC to quantify nonionic surfactants such as polysorbates, depended on the level and the matrix. I primarily used ELSD and matched level in samples to an appropriate standard.

Polysorbates are complex mixtures of various degree substitution as well as some starting material (sorbitan). There are two approaches - one is to separate compounds and do quantitation based on one of the components (but need to stay with the same manufacturer to have the same profile) or elute it as a band with a step gradient. I have couple of methods for LC/ELSD combination.

Thanks both!

Vlad, do you have application notes for your separations?
I guess that I need to use pharmacopeial standard for assay so the "everything in one peak" method is probably preferable.