[D-Ala2]-Deltorphin II peptide

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

Batch to batch variation of the purity

[D-Ala2]deltorphin II is a highly stable amphibian heptapeptide and one of the most potent and selective δ-opioid receptor agonists known, with higher affinity and selectivity for δ-opioid receptors than any endogenous mammalian opioid ligand. It exhibits favorable enzymatic stability in brain membrane homogenates and plasma, with its blood-brain barrier (BBB) permeability influenced by its N-terminal region and residues at positions 4 and 5.

In mice, intracerebroventricular administration of [D-Ala2]deltorphin II produces significant antinociceptive effects, and repeated exposure leads to marked homologous tolerance without cross-tolerance to the δ₁ agonist DPDPE or the μ agonist DAMGO, indicating distinct receptor regulatory mechanisms.

It acts as a selective δ₂-opioid receptor agonist, whose antinociceptive signaling is coupled to Gq proteins and involves inositol-signaling pathways, distinguishing it from δ₁ agonists such as DPDPE, which rely on Go1 proteins.

• Thomas SA, Abbruscato TJ, Hau VS, et al. Structure-activity relationships of a series of [D-Ala2]deltorphin I and II analogues; in vitro blood-brain barrier permeability and stability. J Pharmacol Exp Ther. 1997;281(2):817-825.
• Mattia A, Vanderah T, Mosberg HI, Porreca F. Lack of antinociceptive cross-tolerance between [D-Pen2, D-Pen5]enkephalin and [D-Ala2]deltorphin II in mice: evidence for delta receptor subtypes. J Pharmacol Exp Ther. 1991 Aug;258(2):583-7. PMID: 1650835.
• Sánchez-Blázquez P, Garzón J. delta Opioid receptor subtypes activate inositol-signaling pathways in the production of antinociception. J Pharmacol Exp Ther. 1998 May;285(2):820-7. PMID: 9580632.

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.