Dermorphin | CAS 77614-16-5 | Mu-Opioid Receptor Agonist (Research Use Only) | Knowlux

Product Description

Dermorphin, CAS 77614-16-5, is a synthetic heptapeptide corresponding to the naturally occurring mu-opioid receptor (MOR) agonist originally isolated from the skin of the South American frog Phyllomedusa sauvagei, supplied by Knowlux for laboratory research use. The sequence is H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2, with a D-alanine at position 2 and an amidated C-terminal serine. The molecular formula is C40H50N8O10 and the molecular weight is 802.87 g/mol on a free-peptide basis. Each lot is released with a lot-specific COA, MSDS and analytical traceability.

CAS and Salt Form Clarification: Dermorphin circulates in commercial catalogues under three distinct chemical forms, and the distinctions are material for molecular weight, solubility, and assay design. CAS 77614-16-5 is the free peptide, with formula C40H50N8O10 and MW 802.87, as confirmed by MedChemExpress, PeptideDB, TargetMol, Biorbyt, Adooq, and AbMole. CAS 78331-26-7 is the trifluoroacetate (TFA) salt, with formula C42H51F3N8O12 and MW 916.89, as listed by Sigma-Aldrich, AbMole, Biozol, PeptideDB, and Aobious. A third form, the acetate salt, appears in some supplier listings with formula C42H54N8O12 and MW 862.9 (BenchChem). The TFA salt is the form most commonly supplied by major catalogue vendors for high-purity research grades, and the free peptide is the reference basis for the 802.87 molecular weight. Knowlux specifies the salt form, counter-ion identity, and peptide content per lot on the COA. Buyers should confirm whether the quoted material is free peptide, TFA salt, or acetate salt before procurement, as the TFA counter-ion alone adds approximately 114 g/mol to the free-peptide mass.

Structural Note: The D-alanine at position 2 is the defining structural feature of Dermorphin relative to mammalian opioid peptides. This single D-amino-acid substitution confers resistance to aminopeptidase and dipeptidyl aminopeptidase cleavage, and it is the structural basis for the peptide's high potency and metabolic stability at the mu-opioid receptor. The C-terminus is serinamide (Ser-NH2), amidated against carboxypeptidase attack. Dermorphin is linear, contains no cysteine, and has no intramolecular cross-link, distinguishing its handling profile from the disulfide-constrained peptides in the Linaclotide, Plecanatide, and Ziconotide families. It contains no methionine and no tryptophan, which removes methionine sulfoxide and tryptophan oxidation as principal degradation pathways; the two tyrosine residues (Tyr1 and Tyr5) are the aromatic chromophores and the relevant sites for UV detection at 280 nm.

Product Parameters

Item	Specification
Product Name	Dermorphin
Synonyms	Dermorphin; Dermorphin TFA; Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2
CAS No.	77614-16-5 (free peptide); 78331-26-7 (TFA salt)
Molecular Formula	C40H50N8O10 (free peptide); C42H51F3N8O12 (TFA salt)
Molecular Weight	802.87 g/mol (free peptide); 916.89 g/mol (TFA salt)
Sequence (1-letter)	Y-a-FGYPS-NH2 (D-Ala at position 2)
Sequence (3-letter)	H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2
Sequence Length	7 amino acids, linear
Key Structural Features	D-Ala at position 2 (protease resistance); C-terminal Ser-NH2; two Tyr residues (UV chromophore); no cysteine, methionine, or tryptophan
Appearance	White to off-white powder
Solubility	Free peptide: H2O >=100 mg/mL (batch-tested); TFA salt: H2O 127.5 mg/mL, DMSO 10 mM; acetate salt: DMSO/DMF/ethanol 30 mg/mL (see Solubility section)
Purity	>=95.0% (entry grade); >=98.0% (standard grade); >=99.0% (high-purity grade); 98.82% (TargetMol batch)
Identity	Confirmed by LC-MS and HPLC
Grade	Research grade
Counter-ion	Free peptide, TFA, or acetate (lot-specific, declared on COA)
Peptide Content	>=75.0% to >=80.0% (supplier-dependent)
Water Content	<=8.0% (supplier specification)
Single Impurity	<=2.0% (HPLC; <=1.0% available)
Bacterial Endotoxins	Supplier-dependent; confirm on COA
Storage	See Storage and Stability section
Packaging	1 mg / 5 mg / 10 mg / 25 mg / 50 mg / 100 mg vial; bulk on request
Application	Laboratory research use only
Origin	China

Product Details

1. Overview

Dermorphin is a natural heptapeptide amide first isolated from the skin of the South American frog Phyllomedusa sauvagei. It is one of the most potent and selective endogenous mu-opioid receptor (MOR) agonists known, and its discovery established that amphibian skin is a source of mammalian-type opioid peptides with unusual structural features. The peptide produces profound antinociception in preclinical models and is used as a reference agonist for MOR pharmacology, particularly where high potency and selectivity over delta and kappa receptors are required. In a comparative potency context, Sigma-Aldrich notes that Dermorphin is 30 to 40 times more potent than morphine at the mu-opioid receptor. The material supplied under this specification is research-grade and is not intended for human administration.

2. Receptor Pharmacology and Selectivity

Dermorphin binds the mu-opioid receptor with sub-nanomolar affinity and displays exceptional selectivity over the delta and kappa subtypes. The binding data compiled across multiple sources converge on a narrow range: a Ki of 0.3 to 1.5 nM at MOR, 15 to 62 nM at the delta-opioid receptor (DOR), and greater than 1000 nM at the kappa-opioid receptor (KOR), giving a MOR/DOR selectivity ratio of approximately 10- to 200-fold and a MOR/KOR selectivity ratio exceeding 1000-fold. A specific rat brain membrane binding assay reports a Ki of 0.7 nM and a Kd of 0.46 nM at MOR using [3H]DAMGO as the radioligand. In a functional cAMP inhibition assay in neuroblastoma x glioma hybrid cells, Dermorphin inhibits forskolin-stimulated cAMP with an IC50 of 200 nM. The functional EC50 for MOR activation across GTPgammaS and cAMP assay formats spans approximately 0.5 to 5.0 nM with near-full efficacy (Emax ~100%). The spread across these values reflects differences in assay format (binding versus GTPgammaS versus cAMP), receptor source, and radioligand identity, and the sub-nanomolar binding affinity remains the consensus reference for Dermorphin potency. A distinctive pharmacokinetic property of Dermorphin among opioid peptides is its blood-brain barrier influx rate: BenchChem reports a Kin of 2.18 microliters/(g x min), which is substantially higher than that of DAMGO (Kin 0.18-0.40 microliters/(g x min)) and CTAP (no detectable influx), and is attributed to the D-Ala2 residue and the peptide's overall physicochemical profile. These values are assay- and system-dependent and are provided for scientific reference only.

3. Research Applications

Published pharmacological characterizations and documented protocols describe the following research applications:

• Mu-opioid receptor (MOR) binding and functional agonist assays (radioligand displacement, GTPgammaS binding, cAMP inhibition)

• Opioid receptor selectivity profiling across MOR, DOR, and KOR

• Antinociception and neuropathic pain research models

• Blood-brain barrier permeability and CNS penetration studies of opioid peptides

• D-amino-acid peptide stability and protease-resistance studies

• Comparative pharmacology of amphibian versus mammalian opioid peptides

• Reference standard development for HPLC and LC-MS analytical methods

These descriptions are derived from published research and are provided for scientific reference only.

Quality Control

Test Item	Method	Acceptance Criteria
Purity	RP-HPLC	>=95.0% (entry grade); >=98.0% (standard grade); >=99.0% (high-purity grade); 98.82% (TargetMol batch)
Identity	LC-MS and HPLC	Consistent with structure (802.87 +/- 1 for free peptide; 916.89 +/- 1 for TFA salt)
Single Impurity	RP-HPLC	<=2.0% (entry grade); <=1.0% (higher grade)
Peptide Content	Nitrogen analysis or AAA	>=75.0% to >=80.0% (supplier-dependent)
Water Content	Karl Fischer	<=8.0%
Appearance	Visual	White to off-white powder

Purity specifications for Dermorphin span the 95% to 99% range depending on supplier and salt form. Phoenix Biotech specifies >=95% by HPLC for its free-peptide catalogue item and states that the vial contents are accurately determined to contain the labelled net peptide mass. Sigma-Aldrich specifies >=98% by HPLC for its TFA salt, and Biozol lists 98.00% for the Biorbyt TFA salt lot. AbMole specifies >=98.5%. Omizzur and TsurgeX specify >=99.0%. TargetMol reports a batch purity of 98.82%. The principal quality consideration is the salt-form ambiguity discussed in the Product Description: a lot reported at MW 802.87 is on a free-peptide basis, whereas a TFA salt lot at MW 916.89 includes the trifluoroacetate counter-ion, and an acetate salt lot at MW 862.9 includes the acetate counter-ion. Researchers preparing molar solutions should use the peptide content value and the declared salt basis rather than the HPLC purity figure alone. The free-peptide and TFA salt forms may exhibit different solubility profiles, so the salt basis should also be confirmed where aqueous stock preparation is planned.

Solubility and Handling

Solubility: Dermorphin solubility is salt-form dependent, and the available numeric data are best documented for the free peptide and the TFA salt. For the free peptide, MedChemExpress reports water solubility of >=100 mg/mL (124.55 mM), with the caveat that ">= " means soluble but saturation was not established; AbMole corroborates water solubility of >=100 mg/mL at 25C. For the TFA salt, Biorbyt and Biozol report water solubility of 127.5 mg/mL (139.06 mM) and DMSO solubility of 10 mM at 25C. For the acetate salt, BenchChem reports solubility of 30 mg/mL in DMSO, DMF, and ethanol, and 10 mg/mL in PBS at pH 7.2. The free peptide and TFA salt are therefore freely water-soluble, while the acetate salt is more soluble in polar organic solvents. TargetMol separately reports free-peptide water solubility of 50 mg/mL (62.28 mM) with sonication recommended, which is lower than the MedChemExpress and AbMole >=100 mg/mL figures but still within a practical working range; the difference may reflect lot history or the dissolution technique used. For stock preparation, water is the preferred solvent for the free peptide and TFA salt, and DMSO or DMF is preferred for the acetate salt where an organic vehicle is required. Prepare solutions fresh and aliquot to avoid repeated freeze-thaw cycles.

Handling Precautions: Use powder-handling containment (glove box or fume hood with particulate control). Avoid inhalation of fine powder. Wear nitrile gloves, lab coat, and eye protection. Dermorphin contains no cysteine or methionine, so reducing agents and methionine-oxidation protection measures are not required. The two tyrosine residues are the principal UV chromophores and are not a significant oxidation liability under standard handling conditions. The lyophilized powder is hygroscopic; equilibrate vials to room temperature before opening to prevent condensation.

Storage and Stability

Format	Temperature	Shelf Life
Lyophilized Powder	-20C, sealed, desiccated	1 year (MedChemExpress); 3 years (AbMole, TargetMol); >=4 years (acetate salt, BenchChem)
Lyophilized Powder	-80C, sealed, desiccated	2 years (MedChemExpress)
Lyophilized Powder	4C, sealed, desiccated	2 years (AbMole)
Reconstituted Solution	-80C, aliquoted, sealed	6 months (MedChemExpress, AbMole, TargetMol)
Reconstituted Solution	-20C, aliquoted, sealed	1 month (MedChemExpress, AbMole)

Storage guidance for Dermorphin diverges across suppliers in a way that warrants attention. MedChemExpress specifies 2 years at -80C and 1 year at -20C for powder, with solutions stable for 6 months at -80C or 1 month at -20C under sealed, moisture-free conditions. AbMole and TargetMol specify 3 years at -20C for powder, with AbMole additionally listing 2 years at 4C. BenchChem claims >=4 years of stability at -20C for the acetate salt, which is substantially longer than the other suppliers' claims and may reflect a specific lot history or a different stability-indicating method. Phoenix Biotech recommends storing the peptide in dry form at 0-5C, which is a more conservative bench condition but is not presented as an alternative to -20C for long-term archival preservation. The -20C powder condition is the most widely supported archival temperature across suppliers; -80C is the conservative choice for extended storage of either powder or solutions. The lyophilized powder is hygroscopic; equilibrate vials to room temperature before opening to prevent condensation. Protect from moisture throughout storage.

Documentation Support

Per lot: COA, MSDS, HPLC chromatogram, and mass spectrometry data. Salt-form identity, counter-ion content, and peptide content available on request. Custom specifications and third-party inspection can be arranged on a project basis.

About Knowlux

Knowlux Biotechnology is a GMP-oriented manufacturer and supplier of peptides, APIs and fine-chemical research compounds, operating from Hubei, China. We serve research groups, CDMOs and distributors in more than 40 countries, and support contract synthesis, custom packaging and technical documentation requests.

Compliance Statement

FOR RESEARCH USE ONLY. NOT FOR HUMAN USE. NOT FOR DIAGNOSTIC OR THERAPEUTIC USE.

This product is supplied for laboratory research use only. It is not for human or animal administration, not for diagnostic or therapeutic use, not for retail sale, and not for personal use. Dermorphin is not approved as a medicinal product in any jurisdiction. The purchaser is responsible for verifying product specifications against their specific research requirements and for compliance with all applicable institutional, local, and national regulations governing research chemical acquisition, storage, and use. Research context statements are for scientific reference only and do not constitute medical advice, promotional claims, or dosing guidance.

Data Verification Notes

The free-peptide formula C40H50N8O10 and MW 802.87 are confirmed by MedChemExpress, PeptideDB, TargetMol, Biorbyt, Adooq, and AbMole. The sequence Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2 is confirmed across MedChemExpress, PeptideDB, TargetMol, and Phoenix Biotech. The TFA salt CAS 78331-26-7, formula C42H51F3N8O12, and MW 916.89 are confirmed by Sigma-Aldrich, AbMole, Biozol, PeptideDB, and Aobious. One SCBT COA lists the TFA salt formula as C43H51F3N6O12, which contains one additional carbon and one fewer nitrogen than the consensus C42H51F3N8O12; this is treated as a formula-field error in that specific document, as the molecular weight (916.9) and CAS (78331-26-7) are consistent with the consensus assignment. The acetate salt formula C42H54N8O12 and MW 862.9 are from BenchChem. The MOR Ki range of 0.3-1.5 nM and the DOR/KOR selectivity ratios are from the BenchChem comparative guide. The rat brain membrane Ki of 0.7 nM, Kd of 0.46 nM, and cAMP IC50 of 200 nM are from BenchChem. The blood-brain barrier Kin of 2.18 microliters/(g x min) is from BenchChem and the Van Dorpe et al. Peptides 2010 reference. The 30- to 40-fold potency advantage over morphine is from Sigma-Aldrich. Solubility values are reported with their source conditions and salt-form assignments rather than reconciled into a single figure because the free peptide and TFA salt are water-soluble at >=100 mg/mL, whereas the acetate salt is more soluble in DMSO/DMF/ethanol. Storage shelf-life divergence (1 year versus 3 years at -20C; >=4 years for the acetate salt) is reported as-is; the -20C powder condition is the most widely supported archival temperature, and -80C is presented as the conservative option.

Formatting Note: All formulas, sequences, and comparison operators use plain ASCII notation to prevent character corruption on the platform. Section headings, table alignment, and spacing follow the approved product detail pattern. No trailing spaces or non-breaking characters are used; tables use consistent pipe alignment.