TEAA quantification

[DeadlyTedly]

What is (are) the easiest, least expensive and accurate methods for quantifying TEAA concentration in aqueous and 10-50% organic solns? range 0.020-0.2 M TEAA.

Thanks

[Mark Tracy]

__easy
__cheap
__accurate

Pick any two.

[DeadlyTedly]

Alright, cheap and accurate.

[Mark Tracy]

Titration with a pH meter is cheap, accurate and laborious. You need to do it once with acid and again with base.

If you don't mind expensive, Dionex can sell you a great ion chromatograph.

[DeadlyTedly]

Can you observe an endpoint by titrating 0.02 M solution? Is there a published method that you know of? Better indicators?

We may have an ic somewhere in the company so I'll check that out. I know IC is the "right" solution, just a matter of $$ these days.

Thanks

[Mark Tracy]

Don't use color indicators. Use a pH meter. Dig out your old Quantitative Analysis textbook (e.g. Skoog & West) for how to do the data analysis.

[DeadlyTedly]

Strange indeed, I had the orange beast open in front of me! pH titration using 0.1 N NaOH first followed by an equivalent HCl titration. If I understand this correctly, titrate x mL of each, create a curve and join at the inflection point to read concentration.

Going to give a shot now and I'll keep you posted.