CREKA peptide

CREKA peptide

• COA/MS/HPLC Report
• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

Batch to batch variation of the purity

H-CREKA-OH

H-Cys-Arg-Glu-Lys-Ala-OH

5

95.2%

C₂₃H₄₃N₉O₈S

605.71

Synthetic

Powder

The CREKA pentapeptide (Cys-Arg-Glu-Lys-Ala) was identified through in vivo phage display. It exhibits high affinity for fibrin-fibronectin complexes prevalent in pathological microenvironments. The cysteine residue enables covalent conjugation to nanocarriers such as liposomes and micelles, while its balanced charge distribution enhances target binding specificity. CREKA-modified nanoprobes demonstrate superior site retention and accumulation, enabling precision imaging applications including tumor stroma detection and vascular visualization. Further applications leverage its low immunogenicity for designing targeted molecular delivery systems in biomarker studies and biomedical engineering.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual: Handling and Storage of Synthetic Peptides

• Zhang N, Ru B, Hu J, Xu L, Wan Q, Liu W, Cai W, Zhu T, Ji Z, Guo R, Zhang L, Li S, Tong X. Recent advances of CREKA peptide-based nanoplatforms in biomedical applications. J Nanobiotechnology. 2023 Mar 3;21(1):77. doi: 10.1186/s12951-023-01827-0. PMID: 36869341; PMCID: PMC9985238.

Trifluoroacetic acid (TFA) is a common counterion from the purification process using High-Performance Liquid Chromatography (HPLC). The presence of TFA can affect the peptide's net weight, appearance, and solubility.

Impact on Net Weight: The TFA salt contributes to the total mass of the product. In most cases, the peptide content constitutes >80% of the total weight, with TFA accounting for the remainder.

Solubility: TFA salts generally enhance the solubility of peptides in aqueous solutions.

In Biological Assays: For most standard in vitro assays, the residual TFA levels do not cause interference. However, for highly sensitive cellular or biochemical studies, please be aware of its presence.