P5 peptide

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

Batch to batch variation of the purity

• P5 polypeptide is designed to form peptide-based nanofilaments (PFs) and has been demonstrated to exhibit excellent resistance to non-specific protein adsorption. Through a series of experiments, including turbidity measurement, high-performance liquid chromatography (HPLC), enzyme-linked immunosorbent assay (ELISA), fluorescence resonance energy transfer (FRET), and transmission electron microscopy (TEM), it has been shown that P5Fs (nanofilaments formed by P5) have the lowest adsorption capacity for human serum albumin (HSA) among the studied PFs. This property is crucial for its application as a drug carrier, as it can reduce the formation of a biomolecule corona during circulation in the body, thereby minimizing the risk of being recognized and cleared by the immune system.
• In addition, P5Fs display a favorable biodistribution pattern. In vivo studies in mice have revealed that, compared to other PFs, P5Fs have a relatively lower accumulation in the lungs and a higher retention in the plasma one hour after injection. This distribution characteristic is beneficial for the circulation and penetration of drugs in the body, increasing the likelihood of the drug reaching the target site. Moreover, the docetaxel nanofilaments based on P5Fs (DP5Fs) have exhibited outstanding antitumor activity. In various tumor models, such as human breast cancer MCF - 7 tumors, human lung cancer A549 tumors, human colon cancer HT29 tumors, and human prostate cancer PC3 tumors, DP5Fs have demonstrated higher tumor inhibition rates and better survival benefits for animals than traditional drug formulations. These results suggest that P5 polypeptide holds great promise in the development of novel drug delivery systems and cancer therapies.

• Cai Y, Xu T, Zhu B, Chen J, Jiang L, Shan X, Rong R, Li Y, Yu Y, Gao X, Zhu HH, Zhang L, Zhang P, Li Y. Conformation Influences Biological Fates of Peptide-Based Nanofilaments by Modulating Protein Adsorption and Interfilament Entanglement. Adv Mater. 2024 Nov 28:e2409130. doi: 10.1002/adma.202409130. Epub ahead of print. PMID: 39610201.

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.