a -MSH (11-13) (free acid)KPV

I. Basic Chemical Identification (CAS Official Unique Code)

1. Basic Nomenclature

• English Official Name: L-Lysyl-L-prolyl-L-valine Acetate (KPV Tripeptide)
• Common Abbreviations: KPV, α-MSH (11-13), Anti-inflammatory Tripeptide
• Full Name: L-Lysyl-L-prolyl-L-valine Acetate, Lys-Pro-Val Acetate
• Amino Acid Sequence: L-Lys-L-Pro-L-Val (KPV); it is the amino acid fragment at positions 11-13 of the C-terminal of α-melanocyte-stimulating hormone (α-MSH), a linear tripeptide with no terminal modification, retaining the natural active sequence structure.
• CAS Registry Number: 67727-97-3 (general CAS for free form; the same code is commonly used for acetate in industrial applications).
• Product Category: Synthetic Anti-inflammatory Peptide, Biochemical API, Research-Grade Peptide Reagent, Cosmetic Functional Raw Material
• EC/EINECS: None (Registration is not mandatory for research and industrial peptides, complying with EU REACH research exemption regulations).

2. Basic Molecular Parameters

• Molecular Formula: C₁₆H₃₀N₄O₄ (free base); C₁₈H₃₂N₄O₆ (acetate form).
• Average Molecular Weight: 342.44 Da (free base); 384.47 Da (acetate form).
• Exact Mass-to-Charge Ratio ([M+H]⁺): 343.2345 (free base); 385.2452 (acetate form).
• Theoretical Elemental Analysis (free base): C: 56.12%; H: 8.83%; N: 16.36%; O: 18.69%.
• Isoelectric Point (pI): 9.7 (strongly basic peptide, caused by protonation of the N-terminal amino group and the lysine side chain amino group).
• pH Range for Solution Stability: 4.0 ~ 7.5 (stable in neutral to slightly acidic environment, easy to hydrolyze under strong acid and strong base conditions).

3. Chemical Structure

H-Lys-Pro-Val-OH (linear tripeptide with free N-terminal amino group and free C-terminal carboxyl group; the middle proline is a cyclic imino acid, which endows the molecular conformation with rigidity and improves enzymatic hydrolysis stability; the lysine side chain is positively charged, and valine is a hydrophobic side chain, showing amphiphilicity as a whole).

II. Physical and Chemical Properties (Chemically Tested + Predicted Constants)

1. Appearance and Character

White to off-white loose powder, odorless, no visible foreign matter; no clear crystalline melting point, thermal decomposition occurs when heated above 210℃, belonging to small molecular peptide thermal decomposition material.

2. Thermodynamic Constants (Predicted Values)

• Boiling Point: 1024.5±70.0 ℃ (predicted value, free base).
• Bulk Density: 1.284±0.05 g/cm³ (predicted value, consistent with the density characteristics of short-chain peptides).

3. Solubility (Core Parameter for Chemical Preparation)

• Purified Water/Sterile Water for Injection: Easily soluble, maximum solubility 100 mg/mL (292.1 mM, free base).
• PBS Buffer, Glycerol, Propylene Glycol: Easily soluble, suitable for cosmetic and biological experiment preparation.
• Methanol, Ethanol: Slightly soluble, solubility ≤8 mg/mL.
• Dichloromethane, Ethyl Acetate, n-Hexane: Insoluble.
• Preparation Suggestion: Dissolve quickly in pure water at room temperature without ultrasound; 30℃ water bath can accelerate dissolution, avoid high temperature above 45℃.

4. Solid State and Solution Stability

(1) Solid Powder

• Strong stability and excellent oxidation resistance in dark, sealed and dry environment.
• Frozen storage at -20℃: Shelf life 24 months; ultra-low temperature at -80℃: Shelf life 36 months.
• Strictly prohibit humid environment (humidity >65% is easy to absorb moisture and agglomerate), direct sunlight and high temperature (>30℃ accelerates degradation).

(2) Aqueous Stock Solution

• Room temperature (25℃): Half-life is only 5-10 minutes, easy to be degraded by aminopeptidase/carboxypeptidase, must be prepared and used immediately .
• Refrigeration at 4℃: Stable for ≤24 hours; aliquoted and frozen at -20℃: Stable for ≤30 days.
• Degradation Triggers: Enzymatic hydrolysis, peptide bond hydrolysis, deamidation; no terminal protection, the aqueous solution stability is weaker than that of modified peptides.

III. Synthesis Process (Solid-Phase Peptide Synthesis SPPS, Industrial General Route)

KPV adopts the standard Fmoc solid-phase peptide synthesis process, with simple steps, high yield and easy purity control. The specific chemical mass production process is as follows:

1. Resin Selection: Rink Amide MBHA Resin, C-terminal valine (Val) anchoring to ensure sequence integrity.
2. Sequential Amino Acid Condensation: Coupling according to the sequence Val→Pro→Lys, using HBTU/HOBt/DIPEA condensation system, with each step coupling rate ≥99.2%.
3. Terminal Modification: The industrial mainstream is free form (no N-terminal acetylation or C-terminal amidation), retaining the natural active structure; the modified Ac-KPV-NH₂ requires additional acetylation/amidation steps.
4. Cleavage and Deprotection: Cleave the resin with TFA/triisopropylsilane/water system to gently remove side chain protecting groups and avoid peptide bond breakage.
5. Crude Product Purification: Purify by Reverse-Phase High-Performance Liquid Chromatography (RP-HPLC), with acetonitrile-water-TFA mobile phase to remove impurities such as missing peptides and mismatched peptides.
6. Salt Conversion + Lyophilization: Salt conversion in acetic acid system (acetate finished product), sterile freeze-drying to obtain loose powder.
7. Terminal Quality Control: HPLC purity, ESI-MS molecular weight, amino acid composition, moisture, endotoxin detection, and aliquoted in aluminum-plastic vials after qualification.

IV. Industrial-Grade Quality Standards (Full Set of API COA Indicators)

Industry General Export-Grade Standard (Research/Cosmetic Grade), complying with international peptide raw material quality requirements

V. Storage, Transportation and Packaging Specifications (Chemical Logistics Requirements)

1. Routine Packaging

Lyophilized and sealed in vials: Small specifications of 2mg, 5mg, 10mg, 25mg, 50mg, 100mg; lined with aluminum foil bags + nitrogen protection to isolate moisture and oxygen.

2. Storage Conditions

• Powder: Frozen at -20℃, dark, dry, sealed; ambient humidity ≤60%.
• Strictly prohibit high temperature, humidity, direct sunlight and mixed storage with oxidants, strong acids and strong bases.

3. Transportation Requirements

• Full-process ice pack + cold chain insulation transportation; short-term room temperature (≤25℃) shall not exceed 12 hours.
• Land/Air transportation through general cargo channels, non-hazardous goods, no special transportation qualification restrictions.

VI. Biological Effects and Chemical Application Boundaries (Professional Distinction)

1. Molecular Mechanism of Action (Target Pathway)

• Core Functions: Potent anti-inflammation, immune regulation, mucosal barrier protection, promotion of wound healing, antioxidant stress.
• Action Pathways: Inhibit NF-κB signaling pathway (prevent IκB degradation, block p65 nuclear translocation), inhibit p38 MAPK phosphorylation, reduce the release of pro-inflammatory factors such as TNF-α, IL-1β, IL-6; do not activate MC1R, no melanin-promoting deposition side effects.
• Transport Mechanism: Cross the membrane into cells through PepT1 transporter, enrich in the nucleus to regulate the expression of inflammatory genes, and the bioavailability is better than that of the long-chain parent α-MSH.

2. Application Boundaries (Chemical/Research Definition, Important Compliance)

(1) Legal Uses

• Life science research on anti-inflammatory mechanisms, intestinal barrier, and skin inflammation.
• Cosmetic raw material R&D (external anti-inflammation, soothing, repairing, anti-allergy).
• Animal model research on inflammation, wound healing, IBD and other diseases.

(2) Prohibited Uses

• Unapproved for human drugs, clinical treatment, medical aesthetics injection, oral health care.
• Commercial veterinary use, prohibited use in racehorses/race pets.
• Addition as food, health products, dietary supplements.

VII. Distinction of Easily Confused Products (Avoid Pitfalls in Chemical Procurement)

1. KPV (67727-97-3, Lys-Pro-Val) : Natural α-MSH C-terminal tripeptide, free form/acetate, potent anti-inflammatory without melanin-promoting effect, the main body of this document.
2. Ac-KPV-NH₂ : N-terminal acetylated and C-terminal amidated modified KPV, with stronger stability and longer half-life, CAS: 80498-15-3.
3. α-MSH (1-13) : Full-length thirteen peptide, containing KPV sequence, with both anti-inflammatory and melanin-promoting activities, completely different from KPV in function, structure and CAS.
4. TB500, Epitalon : Non-homologous peptides, with no correlation with KPV in action targets, anti-inflammatory mechanisms and application scenarios.

VIII. Compliance and Industry Notes

• It is a fine chemical peptide raw material dedicated to research/cosmetics, not a drug, veterinary drug or food additive .
• There is no national drug approval number, cosmetic approval number or food approval number in China; it can be used for cosmetic raw material R&D and filing, but not for unapproved medical aesthetics and medicinal scenarios.
• Foreign Trade Export Classification: Biochemical reagents, synthetic peptide raw materials; customs code is classified as amino acid derivatives, complying with international export standards.
• Products are marked "For Research/Cosmetic Raw Material Use Only" , and it is strictly prohibited to be used in human and animal treatment in violation of regulations.