Question

Peptides solution contain 0.1% TFA, how to remove TFA?

Answer 1

TFA removal method depends on the type of peptide solution you are working with.

*If ionic interaction is involved between peptide and TFA then go for ion exchange chromatography.

*To control the pH of the peptide solution: Titrate a peptide stock solution with a base to neutralise the pH.

*One of the effective methods for most of the peptides: HPLC purification with buffers containing acetic acid(CH3COOOH)).

*Formation of TFA salts by Lyophilising the peptide: Dissolve peptide in NH4HCO3 and Lyophilise it again. It gives HCO3- and NH4+ salts. Care must be taken while doing this process because few TFA salts are toxic.

*For small peptides: Prefer ion exchange with a basic resin.

*For large peptides: Prefer elution with NH4CO3 buffer(you can easily remove it by freeze drying process).