Sinapultide peptide

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

Batch to batch variation of the purity

Sinapultide (KL4) is a synthetic peptide designed to mimic the C-terminal segment of surfactant protein B (SP-B), a critical component of pulmonary surfactant. The peptide features a penta-residue repeat sequence (KLLLL) that confers structural plasticity, enabling adaptive helical conformations in response to varying lipid environments. Studies indicate that sinapultide differentially partitions into lipid bilayers depending on fatty acid saturation levels and pH, adopting helical structures that deviate from canonical α-helical geometry. This adaptability facilitates interactions with phospholipids, particularly DPPC and POPG, influencing lipid dynamics and promoting stable monolayer formation at air-water interfaces.

Biophysical analyses, including solid-state NMR and circular dichroism, reveal that sinapultide's helical structure modulates lipid curvature strain and phase behavior, with deeper insertion observed in saturated lipid environments. The peptide's lysine residues are strategically positioned to interact with anionic lipids, enhancing its interfacial activity. These properties underscore sinapultide's role as a functional SP-B analogue, capable of mimicking key biophysical interactions essential for surfactant function without relying on native protein sequences.

• Braide-Moncoeur O, Tran NT, Long JR. Peptide-based synthetic pulmonary surfactant for the treatment of respiratory distress disorders. Curr Opin Chem Biol. 2016 Jun;32:22-8. doi: 10.1016/j.cbpa.2016.02.012. Epub 2016 Mar 10. PMID: 26970670.

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.