??? preparation of tryptophan internal internal standards

[clementgascua]

Hello guys!

am a new person to HPLC and UPLC MS/MS application.

But i urgently need to put a validated method for a collaborative work.

please, can some help me with;
How i must prepare my internal standards for Tryptophan and Kynurenine.
what concentration and what diluent i must used?

when should i add these internal standards?

thank you for your answers in advance.


clement

[PeterPopoff]

These answers depend on what type of stationary phase you use, mobile phases used. concentrations for internal standards should take into considerations what concentration ranges you are trying to measure of the analyte and the sensitivity of your MS. There is no specific answer, these parameters must be adapted to your instrument, method, and source of your analytes.