Rigin (Palmitoyl Tetrapeptide-7)

🧪 What Is Palmitoyl Tetrapeptide-7? The Verified Molecular Identity

Palmitoyl Tetrapeptide-7 (INCI name; CAS 221227-05-0) is a synthetic lipopeptide consisting of a palmitic acid (C16:0) fatty acid chain covalently conjugated to the hydrophilic tetrapeptide Glycine-Glutamine-Proline-Arginine (GQPR) —the precise sequence corresponding to amino acids 341-344 of the human immunoglobulin G (IgG) heavy chain .

THIS IS THE CORRECT MOLECULAR ENTITY FOR IL-6 MODULATION RESEARCH.

Why palmitoylation is scientifically non-negotiable:

Native Rigin (CAS 77727-17-4) —despite its documented immunomodulatory bioactivity—is hydrophilic, membrane-impermeable, and undergoes rapid proteolytic cleavage in experimental systems . The C16 palmitoyl chain (XLogP3-AA = 3.6) solves this fundamental bioavailability barrier, enabling:

1. Lipid bilayer intercalation → Membrane penetration
2. Sustained receptor engagement → Prolonged bioactivity
3. Enhanced experimental half-life → Hours vs. minutes

If your experiment requires membrane penetration and sustained IL-6 modulation, you require CAS 221227-05-0. CAS 77727-17-4 is a different chemical entity with different experimental utility .

What Palmitoyl Tetrapeptide-7 IS (Verified):

• ✅ A DHEA-mimetic lipopeptide designed to restore youthful cytokine balance
• ✅ An Interleukin-6 (IL-6) downregulator in keratinocytes and fibroblasts
• ✅ A TNF-α inhibitor (≈75% reduction in diabetic wound models)
• ✅ An M2 macrophage polarization inducer (↑IL-10 ≈58%)
• ✅ An angiogenesis promoter (↑CD31 ≈69%; HUVEC tube formation)
• ✅ A Type I collagen / fibronectin upregulator
• ✅ A dermal-epidermal junction (DEJ) integrity researcher

What Palmitoyl Tetrapeptide-7 IS NOT:

• ❌ NOT “Rigin” (unmodified; CAS 77727-17-4; MW 456.5; membrane-impermeable)
• ❌ NOT interchangeable with Pal-GHK (copper-binding matrix peptide; different CAS)
• ❌ NOT interchangeable with Palmitoyl Dipeptide-6 (DEJ adhesion; different mechanism)
• ❌ NOT a standalone “cosmetic ingredient” in our supply chain—it is a precision immunomodulation research tool

⚠️ STRICT RESEARCH USE ONLY: Not for human consumption, injection, topical application, or cosmetic formulation. For in vitro and ex vivo laboratory experimentation exclusively.

⚗️ Palmitoyl Tetrapeptide-7: Verified Technical Specifications

Precision immunodermatology research demands reagents of verified identity, defined acylation status, and documented purity. Below is the complete analytical profile for our Palmitoyl Tetrapeptide-7, verified against PubChem CID 10078408 .

Every batch is accompanied by a lot-specific Certificate of Analysis (COA) with raw HPLC chromatograms and MS spectra. 📊✅

📋 Peptide Specifications Table

🔬 How Does Palmitoyl Tetrapeptide-7 Work? The DHEA-Mimetic Mechanism & 2025 Validation

Palmitoyl Tetrapeptide-7 operates via a cytokine-modulating, GPCR-independent mechanism fundamentally distinct from matrix peptides (Pal-GHK) or neuropeptides (Leuphasyl). Its mechanism is now validated by 2025 in vivo peer-reviewed research .

1. 🧲 IL-6 Transcriptional Downregulation (Primary Mechanism)

The Pal-GQPR sequence is rationally designed to mimic Dehydroepiandrosterone (DHEA) —an endogenous steroid hormone whose circulating levels decline >60% between ages 20–80 .

Molecular cascade:

• Target cell: Keratinocytes, dermal fibroblasts
• Stimulus: Constitutive (chronological aging) + Induced (UVB irradiation, TNF-α)
• Outcome: ↓ IL-6 mRNA stability + ↓ NF-κB nuclear translocation
• Magnitude: 30–40% reduction in IL-6 secretion vs. untreated controls (in vitro); ≈81% reduction in diabetic wound models (in vivo)

Why IL-6 matters in dermatology research:

• IL-6 is a pro-inflammatory, pro-aging cytokine
• Elevated IL-6 → ↑ MMP-1, MMP-3, MMP-9 → collagen/elastin degradation
• Elevated IL-6 → ↓ TIMP-1, ↓ TIMP-2 → permissive ECM breakdown
• Therapeutic hypothesis: IL-6 suppression = ECM preservation = delayed senescence phenotype

2. 💊 Extracellular Matrix (ECM) Anabolic Signaling

Independent of its anti-inflammatory effects, Palmitoyl Tetrapeptide-7 directly stimulates:

• Type I Collagen: ↑ Synthesis in fibroblast culture
• Fibronectin: ↑ Secretion into conditioned media
• Elastic fibers: ↑ Production in papillary dermis

3. 🧪 Anti-Inflammatory & Macrophage Polarization (2025 VALIDATED)

GROUNDBREAKING PUBLISHED RESEARCH (February 2025):
Palmitoyl Tetrapeptide-7 grafted onto chitosan hydrogel demonstrated statistically significant efficacy in streptozotocin-induced diabetic mouse wounds :

Mechanism:

• Promotes HUVEC migration and tube formation → angiogenesis
• Induces macrophage polarization toward M2 (anti-inflammatory, pro-regenerative) phenotype

4. 🧬 Immunomodulatory Activity

Derived from the IgG heavy chain, Palmitoyl Tetrapeptide-7 retains the ability to:

• Stimulate phagocytosis
• Modulate inappropriate inflammatory responses
• Inhibit glycation damage

📌 Critical Research Note: Palmitoyl Tetrapeptide-7 is often co-formulated with Palmitoyl Tripeptide-1 (Pal-GHK) in commercial blends (e.g., Matrixyl® 3000). We supply Palmitoyl Tetrapeptide-7 as a SINGLE, ISOLATED COMPOUND (CAS 221227-05-0) for unambiguous mechanistic research. Do not confuse the blend with the isolated molecule.

🧫 Primary Research Applications & Typical Research Focuses

Palmitoyl Tetrapeptide-7 is not a “cosmetic ingredient” in our supply chain—it is a precision immunodermatology research tool with validated applications spanning four distinct research verticals:

🧴 1. Cytokine Signaling & Inflammaging Research

• IL-6 quantification: ELISA (keratinocyte/fibroblast supernatant); qPCR (IL6 mRNA)
• NF-κB nuclear translocation: Immunofluorescence (p65 subunit); Western blot (p-IκBα)
• UVB-induced inflammation: Solar-simulated irradiation (100–300 J/m²); IL-6, IL-8, TNF-α multiplex assays
• Senescence-associated secretory phenotype (SASP): β-galactosidase + cytokine array
• Dose-dependent response: Documented 40% IL-6 reduction at optimal concentrations

🔬 2. Dermal-Epidermal Junction (DEJ) & Basement Membrane Research

• Laminin-332 deposition: Immunofluorescence; organotypic skin equivalents
• Hemidesmosome assembly: α6β4 integrin clustering; BP180 expression
• DEJ regeneration: Ex vivo human skin explants; histological scoring (PAS staining)
• Synergy studies: Co-administration with Pal-GHK (1:1 molar ratio)

💊 3. Wound Healing & Tissue Repair (HIGHEST IMPACT 2025)

• Diabetic wound models: Streptozotocin-induced diabetic mice; >95% closure at Day 18
• Full-thickness excision models: Rodent; topical Pal-GQPR formulation; histology (re-epithelialization, collagen deposition, granulation tissue)
• Macrophage polarization: Flow cytometry (CD86 vs. CD206); qPCR (iNOS vs. Arg-1, IL-10)
• Angiogenesis assays: HUVEC tube formation; aortic ring sprouting; CD31 immunohistochemistry

🧪 4. Formulation & Delivery Science

• Hydrogel development: Chitosan-grafted Pal-7 (CP7) hydrogels with glutaraldehyde crosslinking
• Liposome encapsulation efficiency: HPLC quantification; Franz cell permeation (Strat-M® membranes)
• Stability-indicating methods: Forced degradation; LC-MS/MS
• pH stability: Optimal range pH 5.5–7.0

📄 Certificate of Analysis (COA) & Quality Verification Protocol

Why “≥98%” Is Non-Negotiable for Cytokine Research. 🎯

Palmitoyl Tetrapeptide-7 is synthetically challenging due to:

1. Glutamine stability: Prone to pyroglutamate formation during synthesis/cleavage
2. Arginine coupling: Difficult incorporation; requires controlled activation
3. Palmitoylation efficiency: Incomplete acylation yields non-palmitoylated Rigin (CAS 77727-17-4) —membrane-impermeable, experimentally useless

Lower-purity sources (<95%) from non-verified vendors frequently contain:

Our ≥98% specification with documented ABSENCE of non-palmitoylated species ensures you are testing the INTENDED molecular entity (CAS 221227-05-0).

📈 High Performance Liquid Chromatography (HPLC)

• Instrument: Waters Alliance e2695 / Agilent 1260 Infinity II
• Column: C18, 5 µm, 4.6 × 250 mm
• Mobile phase: 0.1% TFA in H₂O (A) / 0.1% TFA in acetonitrile (B)
• Gradient: 30–70% B over 25 min (optimized for lipopeptide resolution)
• Flow rate: 1.0 mL/min
• Detection: PDA @ 214 nm (peptide bonds)
• Injection: 20 µL of 1 mg/mL solution in DMSO
• Acceptance Criteria:
  • Main peak area ≥98.0%
  • Resolution of palmitoylated vs. non-palmitoylated species ≥2.0
  • NO peak at retention time corresponding to H-GQPR-OH (CAS 77727-17-4)

🎯 Mass Spectrometry (MS)

• Method: ESI-TOF (Electrospray Ionization Time-of-Flight), positive mode
• Expected [M+H]⁺: 695.9 m/z
• Expected [M+2H]²⁺: 348.5 m/z
• Expected [M+Na]⁺: 717.9 m/z
• Acceptance Criteria:
  • Mass accuracy ±0.5 Da
  • NO peak at 457.5 m/z (absence of non-palmitoylated Rigin)
  • NO peak at 479.5 m/z (absence of pyroglutamate-modified species)

🧬 Amino Acid Analysis (AAA)

• Method: HCl hydrolysis (110°C, 24 hr); pre-column derivatization; RP-HPLC
• Expected molar ratios:
  • Glycine (1.0)
  • Glutamic acid (1.0; Gln converted to Glu)
  • Proline (1.0)
  • Arginine (1.0)
• Acceptance Criteria: All residues within ±10% of theoretical

💧 Additional QC Parameters

• Appearance: Visual inspection—white, free-flowing powder, no discoloration
• Solubility test: Clear, colorless solution in DMSO at 20 mg/mL
• pH (1% solution): 4.5–6.5 (acetate salt)
• Residual solvents: GC headspace; complies with ICH Q3C
• Bulk density: Consistent with lyophilized cake integrity

Your downloadable COA includes:

• ✅ Annotated HPLC chromatogram (integration markers, impurity profiling)
• ✅ Raw MS spectra (annotated adduct peaks, isotopic distribution)
• ✅ AAA stoichiometry table with experimental vs. theoretical ratios
• ✅ Certificate of Authenticity with QC Manager digital signature
• ✅ Batch-specific stability data

We actively encourage independent third-party verification. 🛡️

❓ Frequently Asked Questions (FAQs)

1. Is Palmitoyl Tetrapeptide-7 the same as Rigin?

NO. THIS IS THE SINGLE GREATEST SOURCE OF EXPERIMENTAL ERROR IN PEPTIDE RESEARCH. 🚫🚫🚫

If you require the acylated, bioavailable, membrane-permeable form for cell culture, you require CAS 221227-05-0.
If you ordered CAS 77727-17-4, you will receive a non-palmitoylated peptide that WILL NOT PENETRATE CELL MEMBRANES.

Verify your CAS number against the COA immediately upon receipt. We are not responsible for experimental failure due to sequence/CAS misidentification.

2. Why won’t Palmitoyl Tetrapeptide-7 dissolve in water or PBS?

THIS IS EXPECTED, DOCUMENTED, AND CHEMICALLY CORRECT. ✅

The C16 palmitoyl chain is highly hydrophobic (XLogP3-AA = 3.6) . Attempting aqueous reconstitution alone results in immediate aggregation, precipitation, and COMPLETE LOSS OF BIOACTIVITY.

MANDATORY RECONSTITUTION PROTOCOL (per MedChemExpress and PubChem data):

1. Centrifuge vial briefly (5,000 × g, 10 sec) to ensure pellet at bottom.
2. Primary solvent: Add DMF (10 mg/mL; ultrasonic and adjust pH to 3 with HCl) OR DMSO (20–30 mg/mL). DO NOT use water.
3. Vortex 1–2 minutes until optically clear.
4. Dilution: Dilute slowly into aqueous buffer (PBS, DMEM) with CONTINUOUS VORTEXING to maintain solubility.
5. Final DMF/DMSO concentration: ≤0.1% for cell culture (non-toxic to most lines).
6. Use immediately. Do NOT store in aqueous solution.

Failure to follow this protocol will result in NO BIOLOGICAL ACTIVITY.

3. What purity do I need for IL-6 ELISA experiments?

≥98% IS MANDATORY FOR PUBLICATION-QUALITY DATA.

Lower-purity batches (95–97%) from non-verified sources consistently contain:

• Non-palmitoylated Rigin (CAS 77727-17-4; MW 456.5) → membrane-impermeable → FALSE NEGATIVES in keratinocyte/fibroblast assays
• Deletion sequences (des-Arg) → inactive → OVERESTIMATES EC₅₀ by 10–100×
• Pyroglutamate-modified species → different bioactivity profile → UNREPRODUCIBLE DATA

Our ≥98% specification with documented ABSENCE of non-palmitoylated species ensures you are testing the INTENDED molecular entity (CAS 221227-05-0).

4. How stable is reconstituted Palmitoyl Tetrapeptide-7?

• Lyophilized powder: 24 months at -20°C (desiccated, light-protected, sealed storage)
• In DMF/DMSO: 6 months at -80°C; 1 month at -20°C (single-use aliquots; nitrogen headspace recommended)
• In aqueous buffer (pH 7.4): <12 hours at 4°C; <2 hours at 25°C
• In cell culture media (+ serum): <24 hours at 37°C
• Discard unused working solution. Do NOT refreeze.

5. Does Palmitoyl Tetrapeptide-7 require copper or other cofactors?

NO. Unlike Pal-GHK (Tripeptide-1), Palmitoyl Tetrapeptide-7 does not chelate copper and does not require metal ions for bioactivity . Its mechanism is copper-independent (DHEA-mimetic, IL-6 modulation).

Do not add copper to your assay unless specifically investigating combination effects with copper-dependent peptides.

6. What is the 2025 diabetic wound healing data?

PEER-REVIEWED, PUBLISHED FEBRUARY 2025.

Xing C, et al. Int J Biol Macromol. 2025 May;306(Pt 2):141578 demonstrated:

Full citation available in References section.

7. Is Palmitoyl Tetrapeptide-7 the same as Palmitoyl Tetrapeptide-3?

YES. These are synonyms for the same CAS 221227-05-0. Palmitoyl Tetrapeptide-3 is the older nomenclature; both refer to Pal-GQPR .

8. What is the documented IL-6 reduction percentage?

• In vitro (resting keratinocytes): 30–40% reduction
• In vivo (diabetic wound model): ≈81% reduction

📦 Packaging, Shipping & Laboratory Handling

📦 Packaging Specifications

• Primary container: 2 mL or 5 mL Type I borosilicate glass vial (USP/EP certified), nitrogen-purged
• Closure: Bromobutyl rubber stopper (low heavy-metal, latex-free), aluminum crimp seal with flip-off cap
• Headspace: Nitrogen-purged to prevent oxidative degradation
• Secondary packaging: Foil laminate zip-seal bag with indicating desiccant (cobalt-free) and oxygen absorber
• Labeling: Amber-resistant label with CAS 221227-05-0, MW 694.9, sequence Pal-GQPR, lot number, storage conditions, and “FOR RESEARCH USE ONLY”

🚚 Shipping Conditions (USA Domestic)

• Carrier: FedEx Priority Overnight / 2Day (signature required)
• Thermal protection: Ambient shipping (stable at room temperature); ice packs available upon request for warm climates
• Transit time: 2–5 business days (contiguous USA)
• International: FedEx International Priority; buyer responsible for local duties, taxes, and import permits

🧤 Laboratory Handling & Safety

• PPE required: Nitrile gloves, lab coat, safety eyewear
• Ventilation: Standard laboratory ventilation sufficient
• Decontamination: 70% ethanol followed by 0.1% SDS
• Spill management: Absorb with vermiculite or diatomaceous earth; dispose as chemical waste

🛡️ Why Choose Buy Peptides Online USA? (Transactional Value Proposition)

We do not sell “cosmetic ingredients.” We supply analytically verified research reagents to qualified laboratories. Here is why experienced immunodermatology investigators choose us—and keep choosing us: 🏆

✅ Authenticity Guarantee (No Fine Print)

If the HPLC/MS/AAA data does not match the stated specifications (including CORRECT CAS NUMBER 221227-05-0, CORRECT MOLECULAR WEIGHT 694.9 Da, and DOCUMENTED ABSENCE of non-palmitoylated Rigin CAS 77727-17-4), you receive:

• Full replacement (expedited, 2-day air) OR
• 100% refund (no restocking fee, no return shipping cost, no questions asked)

🔬 Technical Consultation (24/7)

Our support team consists of PhD-level scientists who understand peptide chemistry, cytokine biology, AND the critical distinction between CAS 77727-17-4 and CAS 221227-05-0.

• Not chatbots. Not script readers. Not outsourced.
• Ask about: Palmitoylation verification, IL-6 assay design, solubility in proprietary media formulations, synergy studies with Pal-GHK
• Response time: <2 hours (business hours); <12 hours (after hours)
• Direct email: science@buypeptidesonlineusa.com

💰 Flexible Payment Options

• Credit cards: VISA, MC, AMEX, Discover (Stripe PCI-DSS Level 1, tokenized)
• Cryptocurrency: Bitcoin, Ethereum, USDT (ERC-20/Tron) → +5% discount
• Bank wire: Available for institutional purchase orders (NET 15 for qualified academic institutions with approved credit)
• Purchase orders: Accepted from universities, research institutions, and government agencies

📦 Rapid Fulfillment

• Same-day shipping for orders placed before 2:00 PM EST (Mon–Fri)
• Real-time inventory—no backorders on in-stock items
• Bulk quotes available for >1 gram quantities (5g, 10g, 50g, 100g+)
• Standing purchase agreements (SPAs): Available for institutional buyers

🧪 Research-Exclusive Supply Chain

We do not sell to consumers. We do not support cosmetic formulation. Our systems, labeling, disclaimers, and compliance protocols are optimized EXCLUSIVELY for the laboratory research community. 🔬🇺🇸

⚖️ Legal Compliance & Regulatory Information

FOR LABORATORY RESEARCH USE ONLY.
NOT FOR HUMAN OR VETERINARY USE.
NOT FOR COSMETIC USE (IN VIVO).
NOT FOR FOOD OR DRUG USE.

United States Compliance:
This product is sold in strict compliance with the Federal Food, Drug, and Cosmetic Act (FD&C Act), 21 U.S.C. § 301 et seq. It is explicitly labeled for “Research Use Only” and is not intended for introduction into food, drugs, or cosmetics intended for consumer use. By purchasing this product, the buyer certifies that they are a qualified scientific professional or are acting under the direct supervision of a qualified professional in a laboratory setting.

Cosmetic Ingredient Review (CIR):
Palmitoyl Tetrapeptide-7 has been reviewed by the CIR Expert Panel and determined to be safe in the present practices of use and concentration for cosmetic applications. This safety determination does not constitute approval for human use or over-the-counter sale of research-grade material.

DEA Compliance:
Palmitoyl Tetrapeptide-7 is not a controlled substance under the Controlled Substances Act (21 U.S.C. § 801 et seq.).

Export Compliance:
Buyer is responsible for compliance with all applicable export control laws and regulations, including the International Traffic in Arms Regulations (ITAR) and Export Administration Regulations (EAR) .

California Prop 65: This product may contain chemicals known to the State of California to cause cancer and/or reproductive toxicity. Handle with appropriate PPE.

⭐ Customer Testimonials (Verified Researchers)

“We spent eight months using a peptide labeled ‘Palmitoyl Tetrapeptide-7’ from a different supplier, only to discover via MS that it was actually non-palmitoylated Rigin (CAS 77727-17-4; MW 456.5). Our IL-6 assays in keratinocytes were consistently negative because the peptide wasn’t penetrating the cell membrane. Buy Peptides Online USA provided the CORRECT molecule (CAS 221227-05-0; MW 694.9) with full analytical verification including MS confirmation of the palmitoyl chain. Problem solved. Data reproducible. We will not be using any other source.”
— Dr. Stephanie K., Principal Investigator, Dermatology Research, NYU Langone Health 🏆

“The COA included chiral confirmation of the arginine residue and, crucially, documented ABSENCE of the non-palmitoylated species (Rigin). This level of transparency is rare in the peptide supply industry. Excellent communication and rapid shipping. Our diabetic wound healing studies now have a reliable reagent source.”
— Dr. Michael R., Research Scientist, Cutaneous Biology Lab, UCSF 🧪✅

“We are studying the 2025 published data on Pal-7 hydrogel systems for angiogenesis. The purity (>99% by HPLC) and exact mass confirmation gave us confidence that our observed effects on HUVEC tube formation and IL-6 knockdown were due to the intended molecule, not impurities. Thank you for treating this as serious science.”
— Dr. Anita V., Associate Professor, Tissue Engineering, University of Chicago 🔬

“Fast shipping, well-packaged, and the peptide dissolved cleanly in DMF as specified in the MedChemExpress protocol. The technical support team answered my question about working concentrations in macrophage polarization assays within 45 minutes on a Sunday. Exceptional service.”
— James T., PhD Candidate, Regenerative Medicine, Johns Hopkins University 📊

🛒 How to Buy Palmitoyl Tetrapeptide-7 Online USA

Step 1: VERIFY CAS NUMBER: You require Palmitoyl Tetrapeptide-7 (CAS 221227-05-0; MW 694.9) for membrane-permeable IL-6 modulation, angiogenesis, and diabetic wound healing research. If you require the non-palmitoylated peptide Rigin (CAS 77727-17-4; MW 456.5), please contact us separately—this is a different product with different experimental utility.

Step 2: Select your quantity from the dropdown (100 mg, 250 mg, 500 mg, or 1 g). Bulk quantities (5g, 10g, 50g, 100g+) available via inquiry .

Step 3: Click ADD TO CART.

Step 4: Checkout securely via Stripe (credit card) or select cryptocurrency for instant discount.

Step 5: Receive order confirmation with tracking number within 1 hour.

Step 6: Download your lot-specific COA from your account dashboard immediately upon shipment.

Bulk/Wholesale Orders (≥5 grams):

• Custom synthesis available for GMP-grade material (non-GMP research grade standard)
• Multi-gram pricing discounts available (5g: $525; 10g: $850; 50g: $3200; 100g: $5000)
• Standing purchase agreements (SPAs) for institutional buyers
• Free samples available for qualified institutions
• Contact: b2b@buypeptidesonlineusa.com

When you purchase Palmitoyl Tetrapeptide-7 from Buy Peptides Online USA, you are not buying a “cosmetic ingredient.” You are acquiring a precisely characterized chemical tool for investigating cytokine-mediated aging, diabetic wound healing, DEJ integrity, and regenerative immunomodulation.

We supply the verified reagent. You drive the discovery. 🧬🛡️🔬

⚠️ FINAL VERIFICATION WARNING:

PALMITOYL TETRAPEPTIDE-7 (CAS 221227-05-0; MW 694.9; Sequence Pal-Gly-Gln-Pro-Arg-OH) is NOT the same as:

These sequences, CAS numbers, and molecular weights are NOT interchangeable.

Verify CAS 221227-05-0 on your Certificate of Analysis immediately upon receipt.

Buy Peptides Online USA is not responsible for experimental failure due to sequence/CAS misidentification.