Boc-Leu-Lys-Arg-AMC peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

• Falgueyret JP, Black WC, Cromlish W, Desmarais S, Lamontagne S, Mellon C, Riendeau D, Rodan S, Tawa P, Wesolowski G, Bass KE, Venkatraman S, Percival MD. An activity-based probe for the determination of cysteine cathepsin protease activities in whole cells. Anal Biochem. 2004 Dec 15;335(2):218-27. doi: 10.1016/j.ab.2004.09.005. Erratum in: Anal Biochem. 2005 May 15;340(2):380. PMID: 15556560.

Trifluoroacetic acid (TFA) has a significant impact on peptides due to its role in the peptide synthesis process.

TFA is essential for the protonation of peptides that lack basic amino acids such as Arginine (Arg), Histidine (His), and Lysine (Lys), or ones that have blocked N-termini. As a result, peptides often contain TFA salts in the final product.

TFA residues, when present in custom peptides, can cause unpredictable fluctuations in experimental data. At a nanomolar (nM) level, TFA can influence cell experiments, hindering cell growth at low concentrations (as low as 10 nM) and promoting it at higher doses (0.5–7.0 mM). It can also serve as an allosteric regulator on the GlyR of glycine receptors, thereby increasing receptor activity at lower glycine concentrations.

In an in vivo setting, TFA can trifluoroacetylate amino groups in proteins and phospholipids, inducing potentially unwanted antibody responses. Moreover, TFA can impact structure studies as it affects spectrum absorption.