Tetrapeptide-30

Tetrapeptide-30 (PKEK) · CAS 1036207-61-0

The peptide

Tetrapeptide-30 is a synthetic tetrapeptide with the amino-acid sequence Pro-Lys-Glu-Lys (PKEK). Published studies have investigated PKEK as a cosmetic skin-tone ingredient. In experimental work, PKEK was associated with reduced UVB-induced expression of several inflammatory mediators and pigmentation-related signals in keratinocytes. Small controlled human studies have also evaluated PKEK-containing formulations for changes in the appearance and evenness of skin tone. Results from individual studies should not be assumed to apply to every finished formulation.

We sell it under that INCI name, already dissolved. The carrier is either 35% glycerin in water, with the preservation system you select, or our Sea Kelp Bioferment, which ships pre-preserved with Linatural MBS-4. Both carriers are made at 0.16% and at 1.6% Tetrapeptide-30.

500.6

g/mol, PubChem CID 25001762

PKEK

Pro-Lys-Glu-Lys sequence

C22H40N6O7

molecular formula

2

carrier options on this page

Chemical identity

Registry facts for the peptide.

INCI

Tetrapeptide-30

Sequence

Pro-Lys-Glu-Lys (PKEK)

CAS

1036207-61-0

Formula

C22H40N6O7

Molecular weight

Approximately 500.6 g/mol

FDA UNII

H9G9QJT7E2

Formula and molecular weight are from PubChem CID 25001762. The INCI Tetrapeptide-30, CAS registry number 1036207-61-0, and UNII H9G9QJT7E2 come from the FDA Global Substance Registration System entry that PubChem cites. Each of those codes identifies the substance. None of them is an approval, a clearance, or a statement that a finished cosmetic meets FDA or EU rules.

Made to Order

Built fresh on our robotic platform.

Every lot is produced to order in our AI-powered robotic factory. Nothing sits on a warehouse shelf going stale - you get a date-of-manufacture-fresh batch every time.

01

Order placed

You pick a size and quantity. We confirm specs against your formulation if you have one.

02

Robotic production

Your inputs go in. We process, blend, and fill sealed packaging - all inside our AI-powered robotic factory.

03

Batch QC + COA

Every batch is tested for actives, pH, micro, and appearance. A batch-specific COA, SDS, and TDS ship with the order.

How to read the work

What the published studies cover, and what they do not.

Cosmetic skin-tone studies

Published studies have investigated PKEK as a cosmetic skin-tone ingredient. A finding from one trial should not be assumed to hold for every finished formula.

Keratinocyte experiments

In experimental work, PKEK was associated with reduced UVB-induced expression of several inflammatory mediators and pigmentation-related signals in keratinocytes. That evidence is in vitro.

Human studies, kept separate

Small controlled human studies have evaluated PKEK-containing formulas for changes in the appearance and evenness of skin tone. Trials that also included sodium ascorbyl phosphate are a different design from trials of a PKEK formula without that partner.

Supplied as a suspension

We deliver Tetrapeptide-30 already dissolved in 35% glycerin/water or in our Sea Kelp Bioferment, at 0.16% or 1.6%. Add it on cool-down, at or below 40°C.

Study designs, vehicles, and populations differ. A published result is not a claim for the suspension you buy here.

Published research

Peer-reviewed literature for due diligence.

The papers below studied the tetrapeptide PKEK (Pro-Lys-Glu-Lys). Read each arm on its own: keratinocyte experiments, human work without sodium ascorbyl phosphate, human work that combined the two, and ex vivo delivery. A combination result is not evidence for Tetrapeptide-30 used alone, and none of these papers tested the suspensions on this page. We did not run these studies.

3 peer-reviewed papers

In vitro, controlled human studies, and ex vivo delivery

2012

In vitro + human

Experimental Dermatology

Modulation of skin pigmentation by the tetrapeptide PKEK: in vitro and in vivo evidence for skin whitening effects

Marini A, Farwick M, Grether-Beck S, Brenden H, Felsner I, Jaenicke T, et al.

One keratinocyte experiment and four controlled human arms. In human keratinocytes, PKEK was associated with lower UVB-induced transcript levels for IL-6, IL-8, tumor necrosis factor alpha, and POMC. In a biopsy arm, 10 volunteers applied PKEK once a day for four weeks before a UVB exposure; the authors then reported less induction of IL-1 alpha, IL-6, IL-8, tumor necrosis factor alpha, POMC, and tyrosinase. Those two arms did not include sodium ascorbyl phosphate. Three further arms did combine the materials, so their appearance results are not evidence for Tetrapeptide-30 alone: a six-week facial-spot comparison in 39 Caucasian women, where the authors described a larger change for the pair than for either material without the other; an eight-week hand study in 19 Caucasian participants that added PKEK to a sodium ascorbyl phosphate preparation; and an eight-week, twice-daily facial comparison in 27 Japanese women. On the SCINEXA pigmentation score the authors reported a 26 percent shift for the combination and an 18 percent shift for sodium ascorbyl phosphate without PKEK.

DOI PubMed

2011

Human study

Journal of Cosmetic Dermatology

Facial skin-lightening benefits of the tetrapeptide Pro-Lys-Glu-Lys on subjects with skin types V-VI living in South Africa

Farwick M, Maczkiewitz U, Lersch P, Summers B, Rawlings AV.

Controlled human study, not a sodium ascorbyl phosphate combination trial. Participants with Fitzpatrick phototypes V-VI, living in South Africa, used a PKEK-containing formulation or the matching vehicle under double-blind conditions. Specialists scored facial photographs. At 12 weeks the peptide preparation was ahead of the vehicle on overall appearance (P < 0.05) and on evenness of skin tone (P < 0.01). Enrollment included facial melasma and discoloration remaining after inflammation. This is a grading result for one finished formula versus its vehicle. It does not establish the same change for every Tetrapeptide-30 suspension.

DOI PubMed

2018

Ex vivo delivery

European Journal of Pharmaceutics and Biopharmaceutics

Dermal peptide delivery using enhancer molecules and colloidal carrier systems. Part II: Tetrapeptide PKEK

Neubert RHH, Sommer E, Schölzel M, Tuchscherer B, Mrestani Y, Wohlrab J.

Ex vivo penetration work on excised human skin. It does not measure a change in skin tone. The authors compared a conventional cream with a microemulsion, both carrying hydrophilic PKEK. From the cream, about 40 to 58 percent of the peptide entered the skin, and most of that share stayed in the stratum corneum rather than in living layers. From the microemulsion, measured entry was about 94 percent at 100 minutes and about 88 percent at 300 minutes, but much of the peptide reached the receiver fluid instead of remaining in living skin. Relative amounts in the living layers were largely similar for the two vehicles.

DOI PubMed

Source

Chemical record

PubChem CID 25001762 lists molecular formula C22H40N6O7 and a molecular weight of 500.6. FDA GSRS record H9G9QJT7E2 is the UNII for this substance. That record gives the INCI as Tetrapeptide-30 and the CAS registry number as 1036207-61-0. These codes identify the substance. They are not an approval or a clearance.

PubChem FDA GSRS

Source

Patent family

US 2012/0244094 A1 (application 13/502,261; published 27 September 2012; later abandoned) is the United States publication of PCT/EP2010/065588, international publication WO 2011/061024, filed 18 October 2010. That PCT application claims priority to German application DE 10 2009 046 780.7, filed 17 November 2009. Original assignee: Evonik Goldschmidt GmbH. The family is historical documentation of a cosmetic-use filing for the tetrapeptide PKEK. It is not a product comparison, and it is not evidence for any suspension on this page.

US application WO 2011/061024

These citations are for formulation reading. Vehicles, doses, and populations in the papers may not match the suspensions on this page. A published result does not substantiate a claim on your finished product, and it is not an FDA or EU clearance. Read the papers themselves before you write label copy.

Composition

What’s in this suspension.

This is the per-ingredient composition of the suspension as it ships. Updates dynamically when you change the base, strength, or preservation system above. The peptide line shows the TP-30 loading; the preservative line shows the supplier-blend percentage with its sub-ingredients nested below.

Glycerin · 35% Tetrapeptide-30 · 0.16% Linatural™ MBS-4 · 2% Water · 62.84%

Glycerin

CAS56-81-5

Humectant carrier

35%

Tetrapeptide-30

CAS1036207-61-0

Active peptide

0.16%

Linatural^™ MBS-4

Multifunctional preservative

2%

Inside Linatural^™ MBS-4

Propanediol

CAS504-63-2

1.7%

Ethylhexylglycerin

CAS70445-33-9

0.2%

Benzoic Acid

CAS65-85-0

0.1%

Water

CAS7732-18-5

Solvent (balance)

62.84%

Formulation guide

Built for chemists who sweat the details.

Metering

0.5%–5% of the 0.16% suspension, or 0.05%–0.5% of the 1.6% concentrate, for an in-formula peptide level of about 0.0008%–0.008%

How it ships

Already dissolved in the aqueous carrier selected above

Suspension pH

4.5 – 5.1 (target pH of this suspension)

Add at

Cool-down phase, at or below 40°C

Mixing

Stir gently into the cool-down phase so the suspension disperses.

Avoid

Holding the batch above 40°C after the peptide has been added.

Combination studies

Some human studies tested PKEK together with sodium ascorbyl phosphate. Those combination results do not establish the same effect for Tetrapeptide-30 alone.

Preservation here

2% Linatural MBS-4 in this recipe. Set preservation of the finished formula separately.

Documentation

SDS + TDS are issued per recipe (each base / preservative combination has its own regulatory paperwork). The links below swap when you change your selection above. COA is batch-specific and ships with the order.

Safety Data Sheet (SDS)

16-section GHS · Rev. 0.1 · per-recipe

Technical Data Sheet (TDS)

Composition, attributes, formulation guidance · Rev. 0.1

Need something different?

Custom concentrations, an alternative carrier, allergen-free preservation, COA-on-file, or a regulatory packet for a specific market - reach out and we’ll quote.

Compliance & safety

The fine print, in plain English.

What it’s for

Cosmetic raw material for skin-care formulas, leave-on or rinse-off, when you choose to include Tetrapeptide-30 at the metering rates above. This page sells the bulk suspension, not a finished consumer product. Do not ingest it or inject it.

Claims guidance

If you write about skin tone, keep the language cosmetic, and only where your own testing supports it. Do not claim treatment of melasma, post-inflammatory hyperpigmentation, or any other pigmentary condition. A published paper does not substantiate a claim for your finished formula.

Storage

Store at 2–25 °C in the original sealed container, away from direct light.
The shelf-life window printed for the selected recipe is longer when the container is refrigerated.
After opening, follow the use period on the COA.

Regulatory

INCI name: Tetrapeptide-30.
CAS 1036207-61-0 and FDA UNII H9G9QJT7E2 identify the substance. They are not an approval or a clearance.
Hazard classification is in the per-recipe SDS. Use that document, not this page, for the classification.

Handling

Add the suspension on cool-down, at or below 40 °C. The target pH of each recipe is shown in the selector. Safety of a finished formula, including skin tolerance, is for the brand to assess on that formula.

Questions

Documentation, regulatory, custom recipes, COA-on-file requests, or anything else - email materials@formulatelabs.ai and we’ll route to the right person.

Something Exciting is Coming

Tetrapeptide-30

Everything you need on the technical data sheet.

Tetrapeptide-30

Registry facts for the peptide.

Built fresh on our robotic platform.

What the published studies cover, and what they do not.

Peer-reviewed literature for due diligence.

Modulation of skin pigmentation by the tetrapeptide PKEK: in vitro and in vivo evidence for skin whitening effects

Facial skin-lightening benefits of the tetrapeptide Pro-Lys-Glu-Lys on subjects with skin types V-VI living in South Africa

Dermal peptide delivery using enhancer molecules and colloidal carrier systems. Part II: Tetrapeptide PKEK

What’s in this suspension.

Built for chemists who sweat the details.

Documentation

The fine print, in plain English.