Optimization of the hydrochloric acid concentration used for trifluoroacetate removal from synthetic peptides

Trifluoroacetate (CF 3 COO − , or TFA) is almost always present in commercially synthesized peptides. Unfortunately, it has a strong infrared (IR) absorption band at 1673 cm −1 , significantly overlapping or even completely obscuring the amide I band of a peptide. In such cases TFA must be removed from the solution in order to be able to use IR absorption spectroscopy for peptide secondary structure determination. The most convenient and widely...