Chromatography Forum

Has any one used TFA in ACN on HPG pump with wavelength 210 nm. I am getting too much noise. A=0.1% TFA water & B= 0.1 % TFA ACN and i am using flat gradient 70:30 (A:B)

Check the absorbance spectrum of each of the mobile phase components, your CH3CN may be absorbing at 210nm. The TFA may also be absorbing, but at 0.1% that usually isn't too much of a problem - providing you are using a suitable grade.

If you want to eliminate pump mixing noise, premix the 70:30 solvent and degas, and use in just one channel.

Bruce Hamilton

The trials and travails of TFA mobile phases have been discussed many times on this forum. Please search the archives. You will find that your problem is very common, and there are things you can do to minimize the noise, but it will never fully go away.

Lots of information in this article:

http://www.lcgceurope.com/lcgceurope/Th ... tail/45019