AN115: Determination of Trifluoroacetic Acid (TFA) in Peptides

Instrument Type: IC

Trifluoroacetic acid (TFA) is used in the manufacturing process to release synthesized peptides and during reversed-phase HPLC purification of peptides. This application is to evaluate peptides for residual TFA, fluoride, and acetate in commercially prepared peptides using ion chromatography with the IonPac AS14 column and suppressed conductivity detection. This method requires minimal sample preparation, and the analytes, fluoride, acetate, and TFA, are easily separated without significant peptide interference. See AN160 for an RFIC method.

Improved selectivity for sigma peptide standards on a Thermo Scientific Acclaim 300 C18 column with TFA

Instrument Type: HPLC

The Thermo Scientific HPLC system is applied for the analysis of sigma peptide standard with TFA as the mobile phase modifier. The separation is performed on a Thermo Scientific Acclaim 300 C18 HPLC column, with UV detection at 214 nm. Trifluoroacetic acid (TFA) is used as a mobile phase modifier in peptide analysis because it promotes efficient peak shape, in part by suppressing interactions with silanols on the column.

Comparison of the selectivity for sigma peptide standards on a Thermo Scientific Acclaim 300 C18 column with TFA vs formic acid

Instrument Type: HPLC

The Thermo Scientific HPLC system is applied for the comparison of the selectivity for sigma peptide standard with TFA vs formic acid. The separation is performed on a Thermo Scientific Acclaim 300 C18 HPLC column, with UV detection at 214 nm. Formic acid is a weaker acid, and a weaker ion-pairing agent, but gives a stronger signal for electrospray mass spectrometric detection. TFA is a better ion-pairing agent and yields better efficiency, but at the expense of MS performance.

AN160: Determination of Residual Trifluoroacetate in Protein Purification Buffers and Peptide Preparations by Reagent-Free Ion Chromatography

Instrument Type: IC

In this note, we used RFIC to determine the concentration of residual trifluoroacetate (TFA) in samples of interest to the pharmaceutical industry. TFA is used with an acetonitrile gradient on a preparative RP- HPLC column to purify synthetic peptides. TFA is toxic, thus its removal must be reliably measured in products intended for clinical applications. High-capacity IonPac AS18 column was used to separate trace TFA from an excess of chloride, phosphate, and other anions in three different pharmaceutical buffers. This method improved sensitivity allowing more samples to be analyzed directly.