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Palmitoyl Tripeptide-1

Tier 2 · Preclinical
Also known as Pal-GHK · Palmitoyl oligopeptide

The strongest evidence present is Tier 1: a clinical trial in 30 female participants over 8 weeks2 and reference-cited human clinical/RCT studies of topical formulations. However, most of these positive human outcomes involve either the Matrixyl 3000 combination (Pal-Tripeptide-1 + Pal-Tetrapeptide-7) or timed regimens with baicalin, not the isolated peptide. Multiple sources6 note that Pal-GHK alone has not been tested in humans, that no published study has measured its in vivo penetration, and that most efficacy data is supplier-associated (Sederma/Croda) with thin independent replication. Much mechanistic and pharmacokinetic detail is from vendor descriptions, in vitro fibroblast cultures, and Franz diffusion-cell models rather than human pharmacokinetic studies.

Half-life
~7 h
Routes
Topical (cosmetic formulation)
Goals
Skin anti-aging / dermal remodeling · Wrinkle reduction · Skin firmness and elasticity · Wound healing / tissue repair (reported)
Cost / mg
Not recorded

How it works

According to peptide information sources, Palmitoyl Tripeptide-1 (Pal-GHK) is the small collagen-fragment peptide GHK (glycine-histidine-lysine) with a fatty (palmitic acid) tail attached to its N-terminus. Sources explain that GHK is naturally released when type I collagen breaks down and acts as a 'matrikine' — a signal that tells skin fibroblast cells to make new collagen and other matrix components. The fatty tail is described as a delivery vehicle that helps the otherwise water-loving peptide cross the oily outer skin barrier. Reference and reference-cited studies report that, in lab-grown skin cells, the peptide stimulates collagen and elastin production, appears to work through the TGF-β signaling pathway, and may reduce inflammation. Several sources stress that Pal-GHK is a copper-free analog and, unlike GHK-Cu, does not deliver copper ions.

Overview

Overview

Palmitoyl Tripeptide-1 (also called Pal-GHK or palmitoyl oligopeptide) is described across the source set as a synthetic lipopeptide: the tripeptide glycyl-L-histidyl-L-lysine (GHK) conjugated at its N-terminus to palmitic acid, a 16-carbon saturated fatty acid. The CIR Expert Panel describes it, alongside related peptides, as functioning primarily as a skin conditioning agent in cosmetics.

Origin and structure

A peptide information site states the GHK sequence was originally identified in 1973 by Loren Pickart and Marguerite Thaler as a factor in young human plasma capable of stimulating aged liver tissue to synthesize proteins in a pattern resembling younger tissue(vendor claim). The CIR review notes GHK is a liver growth factor peptide and a fragment of type I collagen; one source and7 (via one source) describe GHK as present within the alpha-2(I) chain of type I collagen and liberated by proteases during collagen degradation, functioning as a matrikine that signals surrounding cells to synthesize new matrix. Several sources emphasize that Pal-GHK is a copper-free structural analog of GHK-Cu and does not deliver copper ions — a distinction blurred by one source and5, which discuss it in the context of the copper-containing pal-GHK-Cu, a distinct compound.

Formulation context

A peptide information site states Palmitoyl Tripeptide-1 is one of two active components of Matrixyl 3000, Sederma's dual-peptide complex combining Pal-GHK with palmitoyl tetrapeptide-7 (Pal-GQPR), and is incorporated into commercial formulations including Haloxyl and Maxi-Lip(vendor claim). A peptide reference site notes that within Matrixyl 3000, Pal-Tripeptide-1 drives collagen neosynthesis while Palmitoyl Tetrapeptide-7 reduces inflammatory cytokine production, particularly IL-6(vendor claim).

Reported activity and evidence

In vitro and reference-cited work reports collagen-stimulating activity. Lintner et al. (2009) reported that in human dermal fibroblast cultures the peptide stimulated collagen synthesis dose-dependently, with significant upregulation of procollagen I and III and increases in fibronectin and glycosaminoglycan synthesis — an effect described as comparable to or greater than retinol at equivalent concentrations under certain assay conditions. A vendor cites 2.3-fold increases in procollagen at 5-10 ppm and, in human dermal fibroblast cultures, a 2.3-fold rise in type I collagen mRNA and 1.8-fold rise in elastin after 72-hour exposure at 10 ppm (one source,9 for methodology of related peptides). A review titled 'Topically applied GHK as an anti-wrinkle peptide'6 reports that, based on cellular studies, GHK can be considered an anti-wrinkle ingredient with tissue-regeneration, collagen/glycosaminoglycan-enhancing, nerve-outgrowth, angiogenic and wound-healing properties.

Human data largely involve combinations rather than the isolated peptide. A reference site reports clinical evaluation of Matrixyl 3000 at 3% twice daily for 56 days showed measurable improvements in wrinkle depth, firmness and texture(vendor claim); Robinson et al. (2005) documented wrinkle-volume reduction and improved skin roughness by profilometry; a peptide list site reports wrinkle-depth reductions of about 20-30% versus placebo at 8-16 weeks of twice-daily Matrixyl 3000 use. A peptide reference site reports clinical studies with twice-daily creams containing ~3 ppm Pal-GHK improving periorbital wrinkle depth and length, and cites a 4-week eye-zone study finding a 39% reduction in wrinkle length, 23% reduction in wrinkle depth, and 17% reduction in overall roughness versus vehicle(vendor claim). A clinical trial in 30 female participants over 8 weeks reported that nighttime PT-1 as part of a timed regimen (with daytime baicalin) improved skin luminance (+16.29%), reduced nasolabial fold depth (-36.35%) and improved firmness (R2: +24.35%), with an animal component reporting increased collagen fiber density2. A single tier-4 site makes the largest claims — up to 55% collagen density increase and 19% elasticity improvement over 12 weeks — which are not corroborated elsewhere.

Important evidence caveats

Multiple sources caution that Pal-GHK alone has not been tested in humans and that no published study has measured its in vivo penetration6. A peptide list site notes most published efficacy data is supplier-associated (Sederma/Croda), that independent replication at clinically relevant concentrations is thin, and assigns a 58% overall confidence rating; a tier-2 review notes a 'surprising absence' of clinical studies on GHK-Cu and Pal-GHK despite their wide cosmetic use6. Src-8 characterizes the evidence base as 1 human study, 2 animal studies and 3 in vitro studies.

What the research shows

48 findings extracted from the 10 sources cited below, strongest evidence first within each group. Every one links to the source it came from.

What human studies found

Based on 3 human trial findings, 1 animal finding, 1 in vitro finding and 1 expert opinion finding.

  • human trialTopical PT-1 applied at nighttime as part of a timed regimen improved skin luminance (+16.29%)2

  • human trialTopical PT-1 applied at nighttime as part of a timed regimen reduced nasolabial fold depth (-36.35%)2

  • human trialTopical PT-1 applied at nighttime as part of a timed regimen improved skin firmness (R2: +24.35%)2

  • animalTime-coordinated nighttime application of PT-1 in combination with daytime baicalin increases collagen fiber density2

  • in vitroBased on cellular studies, GHK can be considered as an anti-wrinkle ingredient6

  • expert opinionThere is a surprising absence of clinical studies using GHK-Cu and Pal-GHK6

How it works

Based on 2 human trial findings, 9 in vitro findings, 10 expert opinion findings and 1 theoretical finding.

  • human trialPalmitoyl tripeptide-1 (PT-1) at nighttime boosts nighttime collagen synthesis2

  • human trialPT-1 works synergistically with daytime baicalin to optimize collagen metabolism through circadian-coordinated application2

  • in vitroPalmitoyl-containing peptides (palmitoyl hexapeptide-12, caffeoyl hexapeptide-9, palmitoyl pentapeptide-4) demonstrate sequence homology with extracellular matrix proteins in the skin (collagen, elastin, fibronectin) without safety concerns3

  • in vitroCosmetic peptides including Palmitoyl Tripeptide-1 have claimed biological activities including signaling to increase collagen and hyaluronic acid production4

  • in vitroPalmitoyl copper peptide (pal-GHK-Cu) is composed of glycyl-L-histidyl-L-lysine-copper5

  • in vitroCP-AcT effectively promotes melanin production in both human A375 and mouse B16 melanoma cell lines5

  • in vitroCP-AcT affects tyrosinase activity both extracellularly and intracellularly5

  • in vitroCP-AcT affects expression of melanin-related genes in A375 cells5

Show 14 more findings

  • in vitroCP-AcT affects expression of tyrosinase (TYR), dopachrome tautomerase (DCT), and endothelin 3 (EDN3) proteins5

  • in vitroGHK has capability of tissue regeneration and enhancement of collagen and glycosaminoglycans synthesis6

  • in vitroGHK is able to increase nerve outgrowth and angiogenesis6

  • expert opinionPalmitoyl tripeptide-1 has the peptide sequence Gly-His-Lys (GHK)1

  • expert opinionThe GHK sequence is a liver growth factor peptide and a fragment of type I collagen1

  • expert opinionPalmitoyl tripeptide-1 is a fatty acyl derivative with a palmitic acid group attached to the N-terminus of the tripeptide1

  • expert opinionA safety evaluation framework for peptides in cosmetics incorporates bioinformatic tools including BLASTp, ToxinPred3.0, Peptipedia, BIOPEP-UWM, AllerCatPro 2.0, and IEDB3

  • expert opinionTripeptides regulate key processes such as cell migration, proliferation, and differentiation8

  • expert opinionTripeptides modulate inflammation, promote angiogenesis, and facilitate extracellular matrix (ECM) remodeling8

  • expert opinionTripeptides can stimulate fibroblast migration and enhance collagen deposition8

  • expert opinionPalmitoyl oligopeptide ingredients are structurally related by an identical fatty, hydrophobic tail connected to a variable sequence of peptides9

  • expert opinionFatty acid peptide ingredients are created using solid-phase peptide synthesis9

  • expert opinionSome small peptides are potent stimulators of angiogenesis9

  • theoreticalPalmitoylated GHK (Pal-GHK) is a palmitoylated derivative of GHK peptide6

Dosing

Based on 1 expert opinion finding.

  • expert opinionTypical use concentrations of these ingredients are < 10 ppm1

How the body handles it

Based on 3 in vitro findings and 1 theoretical finding.

  • in vitroMetal complexation and chemical modification with a hydrophobic moiety increase permeability of GHK peptide6

  • in vitroCell penetrating peptides seem promising to increase skin permeation of GHK and its derivatives6

  • in vitroFormulation influences pal-KTTKS availability7

  • theoreticalSkin pretreatment with microneedles has the potential to enhance permeation of such peptides6

Safety and side effects

Based on 1 in vitro finding, 2 expert opinion findings and 2 theoretical findings.

  • in vitroCP-AcT (palmitoyl copper peptide and acetyl tyrosine combination) showed no cytotoxicity at tested concentrations in HaCat, HFF, A375, and B16 cells5

  • expert opinionThe Panel concluded that these ingredients are safe in the present practices of use and concentration in cosmetics based on low use concentrations and negative safety test data1

  • expert opinionPalmitoyl tripeptide-1, hexapeptide-12, their metal salts and fatty acyl derivatives, and palmitoyl tetrapeptide-7 are safe in the present practices of use and concentration9

  • theoreticalPeptide ingredients encounter challenges mainly due to their hydrophilic nature (high aqueous solubility and low partition coefficient) and instability6

  • theoreticalAngiogenic activity in small peptides might promote tumor growth and metastasis in people with undiagnosed skin cancer9

What people use it for

Based on 2 in vitro findings, 4 expert opinion findings and 1 theoretical finding.

  • in vitroPalmitoyl Tripeptide-1 is a commercially available cosmetic peptide4

  • in vitroGHK has properties for wound healing and prevention/reduction of wrinkles6

  • expert opinionPalmitoyl tripeptide-1, palmitoyl hexapeptide-12, tripeptide-1, and copper tripeptide-1, and palmitoyl tetrapeptide-7 function primarily as skin conditioning agents1

  • expert opinionPalmitoyl tripeptide-1 is used in cosmetic products and requires safety evaluation3

  • expert opinionCopper peptide possesses anti-aging, anti-inflammatory, and wound healing properties5

  • expert opinionGHK-Cu and Pal-GHK are widely used in anti-wrinkle products available on the cosmetic market6

  • theoreticalPalmitoyl peptides are anti-aging agents widely used in cosmetics7

Other findings

Based on 3 in vitro findings.

  • in vitroCosmetic peptides are produced either through chemical synthesis or via biotechnological processes4

  • in vitroMS/MS detection is specific regarding placebo formulations for palmitoyl peptides7

  • in vitroPalmitoylated pentapeptide palmitoyl-lysyl-threonyl-threonyl-lysyl-serine (pal-KTTKS) can be reliably assayed in anti-wrinkle creams7

Points of contention

Where the evidence is unsettled, thin, or says less than the popular claim — worth knowing before you draw conclusions.

Contested

Molecular weight and formula reported inconsistently

Pal-GHK (Palmitoyl Tripeptide-1) Dosage Guide: How Much gives 342.5 Da for the base peptide; Palmitoyl Tripeptide-1 (Pal-GHK): Research Evidence & Safety Profile | PeptideInsight and Palmitoyl Tripeptide-1 Dosing, Need to Know… | Peptide Initiative give 578.79 g/mol with formula C30H54N6O5; PAL-GHK (Palmitoyl Tripeptide-1): Collagen-Boosting Peptide Research | PeptideGuide gives 578.8 g/mol with formula C26H48N4O5; Palmitoyl Tripeptide-1: Evidence & Research | Peptidings gives ~578 Da. The formulas and weights do not all agree.

Limited evidence

No human trials of Pal-GHK alone; efficacy data is largely supplier-associated

Palmitoyl Tripeptide-1: Evidence & Research | Peptidings and Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. state that Pal-GHK alone has not been tested in humans and that no published study has measured its in vivo penetration; Palmitoyl Tripeptide-1 (Pal-GHK, Biopeptide CL, Palmitoyl Oligopeptide) | Peptide List notes most efficacy data comes from the supplier (Sederma/Croda) with thin independent replication; Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. notes a surprising absence of clinical studies. Most positive clinical outcomes come from the Matrixyl 3000 combination (Pal-Tripeptide-1 + Pal-Tetrapeptide-7), not the isolated peptide.

Single source

Largest efficacy claims (55% collagen density, 19% elasticity) come from a single low-tier source

The 55% collagen density increase and 19% elasticity improvement over 12 weeks are reported only by a tier-4 site (Palmitoyl Tripeptide-1 Dosing, Need to Know… | Peptide Initiative); the developer date (2002, Lipotec) is also unique to this source and conflicts with attribution of Matrixyl 3000 to Sederma (Palmitoyl Tripeptide-1 (Pal-GHK): Research Evidence & Safety Profile | PeptideInsight).

Limited evidence

Many mechanism and pharmacokinetic figures are vendor/theoretical, not from human data

Half-lives (6-8 h aqueous, 24-48 h lipid), transdermal penetration percentages (12-15%, 18-22%, 8-12%), and fold-increases in collagen/elastin are drawn from vendor descriptions and in vitro/Franz-cell models (Pal-GHK (Palmitoyl Tripeptide-1) Dosage Guide: How Much), not human pharmacokinetic studies.

Other

Theoretical safety concern about angiogenesis raised by regulator

The CIR peptides review (Safety Assessment of Tripeptide-1, Hexapeptide-12, their Metal Salts ...) notes that some small peptides stimulate angiogenesis, which might theoretically promote tumor growth in people with undiagnosed skin cancer, though the same panel concluded the ingredients are safe at present use concentrations.

Using it with other compounds

Check a stack
  • TB-500Complementary

    No documented conflict

    TB-500 (thymosin β4 fragment) promotes cell migration, angiogenesis and anti-inflammatory tissue repair, while Pal-GHK drives collagen and matrix deposition. They converge on the same goal of tissue healing through distinct pathways (actin/cytoskeletal remodeling vs TGF-β collagen synthesis), so they can be viewed as complementary for repair contexts.

    Tier 4Theoretical — not established

    Shares anti inflammatory · tissue repair

  • PTD-DBMComplementary

    No documented conflict

    Palmitoyl Tripeptide-1 (Pal-GHK) stimulates collagen and elastin through TGF-beta/Smad matrikine signaling, whereas PTD-DBM works through Wnt/beta-catenin. Both feed the same goal of dermal-matrix rebuilding through different pathways, making them a reasonable complementary skin/collagen pairing.

    Tier 4Theoretical — not established

    Timing Both topical; can be combined in a skincare routine.

    Shares collagen synthesis · dermal matrix · tissue repair

  • GLOWSame downstream effect

    No documented conflict

    Palmitoyl Tripeptide-1 is Pal-GHK — essentially a lipidated topical version of the same GHK peptide already delivered (as GHK-Cu) in GLOW. Both drive collagen and matrix synthesis, so a topical Pal-GHK complements GLOW's systemic action, but be aware you are hitting the same GHK matrikine pathway rather than adding a truly independent mechanism.

    Tier 4Theoretical — not established

    Shares collagen synthesis · dermal matrix · tissue repair · anti inflammatory

  • ElafinComplementary

    May be complementary

    In a skin-matrix context these are complementary: palmitoyl tripeptide-1 (Pal-GHK) stimulates collagen/elastin synthesis and suppresses MMPs, while elafin protects the dermal matrix by inhibiting elastase and other proteases that degrade elastin. One builds the matrix, the other guards it from enzymatic breakdown.

    Tier 4Theoretical — not established

    Shares anti inflammatory · dermal matrix · tissue repair

  • MatrixylComplementary

    May be complementary

    Both are palmitoylated matrikine peptides that drive fibroblasts to make more collagen and rebuild the dermal matrix, but they come from different collagen fragments and hit the pathway somewhat differently (Matrixyl/Pal-KTTKS via a fibroblast matrikine/TGF-beta route; Pal-GHK via broad gene modulation and MMP suppression). Because they converge on the same skin-firming, wrinkle-reducing outcome through non-identical routes, they are frequently layered together in topical formulas and are considered additive rather than redundant.

    Tier 3Largely anecdotal — commonly discussed

    Timing Topical use — can be applied together in the same routine.

    Shares collagen synthesis · dermal matrix · tissue repair

  • ArgirelineComplementary

    May be complementary

    Palmitoyl Tripeptide-1 (Pal-GHK) drives collagen, elastin and matrix synthesis in the dermis, complementing Argireline's relaxation of the facial muscles that fold the skin. One works on the underlying structural scaffold while the other reduces the repetitive creasing, so together they can address both static and dynamic contributors to lines.

    Tier 4Theoretical — not established

    Shares collagen synthesis

  • Palmitoyl Tetrapeptide-7Complementary

    May be complementary

    These two are the classic 'Matrixyl 3000' pairing in cosmetic formulations. Palmitoyl Tripeptide-1 (Pal-GHK) is a matrikine that actively drives fibroblasts to build new collagen, elastin and glycosaminoglycans, while Palmitoyl Tetrapeptide-7 works from the other direction — calming inflammatory cytokines (IL-6, IL-1β) and protecting the existing matrix from MMP-driven breakdown. Building plus protecting is exactly the kind of different-mechanism convergence that makes them a well-established, synergistic skin-firmness combination.

    Tier 3Largely anecdotal — commonly discussed

    Timing Topical; apply together in the same routine.

    Shares dermal matrix · anti inflammatory

  • LeuphasylComplementary

    May be complementary

    Palmitoyl Tripeptide-1 (Pal-GHK) stimulates collagen, elastin and matrix synthesis through matrikine/TGF-β signaling, a structural route that is different from Leuphasyl's muscle-relaxing action. Pairing dermal-matrix building with dynamic-line relaxation targets wrinkles from two independent angles.

    Tier 3Largely anecdotal — commonly discussed

    Timing Topical; apply together.

    Shares dermal matrix · collagen synthesis

Safety and side effects

Safety

Regulatory / expert-panel assessment

The CIR Expert Panel concluded that palmitoyl tripeptide-1 and related ingredients are safe in the present practices of use and concentration in cosmetics, based on low use concentrations and negative safety test data1,9. A bioinformatic safety evaluation using tools including BLASTp, ToxinPred3.0, Peptipedia, BIOPEP-UWM, AllerCatPro 2.0 and IEDB reports that palmitoyl-containing peptides demonstrate sequence homology with skin ECM proteins (collagen, elastin, fibronectin) without safety concerns3. A peptide vendor states Pal-GHK has an exceptionally high safety profile when used topically, being non-irritating and well-tolerated by most skin types(vendor claim).

Theoretical concern raised by regulator

The CIR peptides review notes that some small peptides are potent stimulators of angiogenesis, and that this angiogenic activity might theoretically promote tumor growth and metastasis in people with undiagnosed skin cancer9 — though the same panel concluded the ingredients are safe at present use concentrations. A separate review similarly notes tripeptides can promote angiogenesis and ECM remodeling8. An in vitro study of a related palmitoyl copper peptide + acetyl tyrosine combination reported no cytotoxicity at tested concentrations (0-8 μg/mL) across HaCat, HFF, A375 and B16 cells, but also that it promoted melanin production in melanoma cell lines by affecting tyrosinase activity5; note this concerns the copper-containing compound, which sources distinguish from copper-free Pal-GHK.

Not approved for injection or human consumption

A vendor dosing guide states Pal-GHK is not approved for injection, is available for research purposes only, is not FDA-approved for therapeutic use, and is prohibited for human consumption outside clinical trials(vendor claim). A peptide guide notes that while GHK-Cu is studied in tissue-repair, gene-expression and injectable research contexts, Pal-GHK is not(vendor claim).

Anecdotal reports

A peptide vendor reports that users describe noticeable improvements in skin firmness, wrinkle reduction, enhanced healing from procedures or trauma, and improved overall skin quality within weeks(vendor claim) — an anecdotal, uncontrolled account.

Evidence limitation as a safety consideration

Because several sources note that no human trial has tested Pal-GHK alone and no published study has measured its in vivo penetration6, the human safety experience for the isolated peptide specifically (as opposed to the Matrixyl 3000 complex and low-concentration cosmetic use assessed by CIR) is limited.

Reconstitution and handling

Dosing & Preparation

No dose has been established for this compound as a therapeutic. There is no FDA/EMA label for Palmitoyl Tripeptide-1; a vendor guide explicitly states it is not FDA-approved for therapeutic use, is not approved for injection, and is available for research purposes only(vendor claim). The figures below are what sources report — for topical cosmetic formulation contexts — not medical guidance, and they conflict sharply depending on whether 'pure peptide' or 'complex/formulation' concentration is meant.

Reported use concentrations (topical, cosmetic)

  • The CIR Expert Panel reports typical use concentrations of these ingredients are less than 10 ppm1; a tier-4 site similarly states under 10 ppm (<0.001%) in finished product.
  • A vendor dosing guide gives a standard topical range of 2-10 ppm, with most commercial products at 3-5 ppm(vendor claim).
  • A peptide reference site states the peptide is effective at 0.5-3 ppm pure peptide in a finished formulation, with a typical topical range of 2-5% applied twice daily(vendor claim).
  • A peptide vendor claims usage at 100-500 ppm, with a wrinkle-reduction protocol of 3-5% complex twice daily and a skin-barrier protocol of 1-2% complex once daily(vendor claim).

These ranges are inconsistent and largely reflect the difference between pure-peptide and complex/formulation concentrations; treat them as reported figures, not consensus.

Application timing (reported)

  • A vendor source states twice-daily application showed superior efficacy versus single daily dosing in 12-week comparative studies measuring dermal thickness by ultrasound(vendor claim).
  • A vendor guide describes a typical application cycle of 12-24 weeks of continuous use to assess dermal remodeling based on collagen-synthesis timelines(vendor claim); other sources report visible results after 4-8 weeks or 8-12 weeks.
  • A clinical trial reports nighttime application boosting nighttime collagen synthesis and working synergistically with daytime baicalin via circadian-coordinated application2.

Physicochemical / delivery notes

A vendor source notes the 342.5 Da base-peptide molecular weight falls within the optimal range for topical delivery (under 500 Da)8. Note that 342.5 Da is the weight of the unconjugated GHK peptide; the actual palmitoylated molecule delivered — palmitoyl tripeptide-1 — is reported by most sources at ~578 Da (formula C30H54N6O5), which exceeds the cited 500 Da threshold, so the '<500 Da' penetration rationale does not straightforwardly apply to the lipopeptide itself. Reported transdermal figures come from in vitro Franz diffusion-cell models and vendor formulation data, not human PK: 12-15% transdermal penetration within 24 hours versus 2-3% for unconjugated GHK10; a liposomal suspension achieving 18-22% bioavailability, a hydrogel matrix 8-12%, and a research solution range of 0.5-20 ppm (6 for one source). A tier-2 review notes unmodified GHK is hydrophilic with poor topical bioavailability (high aqueous solubility, low partition coefficient) and that chemical modification with a hydrophobic moiety increases its permeability6.

Storage (vendor)

A peptide vendor recommends storage at -20°C or below (-80°C for long-term storage up to 2-3 years; 2-8°C for short-term), and states 4 weeks (28 days) of optimal potency when reconstituted with bacteriostatic water(vendor claim). Reconstitution volume determines final concentration and is a calculation about the container: dividing the vial's peptide mass by the volume of bacteriostatic water added yields the per-mL concentration.

No human trial has established or validated any injection dose; the compound as described in these sources is a topical cosmetic ingredient.

Sources

Ordered by evidence quality — the strongest first.

  1. Safety Assessment of Tripeptide-1, Hexapeptide-12, their Metal Salts and Fatty Acyl Derivatives, and Palmitoyl Tetrapeptide-7 as Used in Cosmetics(opens in a new tab)
    Tier 1Web · cir-safety.org
  2. Targeting Circadian Rhythm for the Regulation of Skin Collagen Metabolism.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov · 2026
  3. A framework for the safety evaluation of peptides in cosmetics(opens in a new tab)
    Tier 2Web · pmc.ncbi.nlm.nih.gov
  4. Bioactive peptides in cosmetic formulations: Review of current in vitro and ex vivo evidence(opens in a new tab)
    Tier 2Web · sciencedirect.com
  5. Palmitoyl copper peptide and acetyl tyrosine complex enhances melanin production in both A375 and B16 cell lines.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2025
  6. Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2025
  7. Development of a LC-MS/MS method to monitor palmitoyl peptides content in anti-wrinkle cosmetics.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov · 2009
  8. Exploring the Role of Tripeptides in Wound Healing and Skin Regeneration: A Comprehensive Review(opens in a new tab)
    Tier 3Web · pmc.ncbi.nlm.nih.gov
  9. Safety Assessment of Tripeptide-1, Hexapeptide-12, their Metal Salts ...(opens in a new tab)
    Tier 3Web · cir-safety.org
  10. Therapeutic Peptides in Aesthetic, Metabolic and Endocrine Conditions: Effects, Safety, Clinical Applications, and Future Perspectives(opens in a new tab)
    Tier 4Web · mdpi.com

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