Compound monograph
Matrixyl
Palmitoyl pentapeptide-4 is the pentapeptide KTTKS with an N-terminal palmitoyl group, corresponding to a fragment sequence of type I procollagen.
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Identity & nomenclature
Palmitoyl pentapeptide-4 is the pentapeptide KTTKS with an N-terminal palmitoyl group, corresponding to a fragment sequence of type I procollagen.
Matrixyl is a trade name for palmitoyl pentapeptide-4, the pentapeptide Lys-Thr-Thr-Lys-Ser (KTTKS) carrying an N-terminal palmitoyl group. The source review notes that KTTKS has become erroneously associated with the term pentapeptide in cosmetic marketing, and that the material has also been designated palmitoyl pentapeptide-3 under earlier INCI naming. Identity should be established against CAS 214047-00-4.
Canonical name: Palmitoyl pentapeptide-4.
Declared aliases and development codes: Pal-KTTKS, Palmitoyl-KTTKS, Palmitoyl pentapeptide-3.
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Molecular properties
| Molecular formula | C39H75N7O10 |
|---|---|
| Molecular mass | 802.1 Da |
| CAS Registry Number | 214047-00-4 |
| PubChem CID | 9897237 |
| UNII | KK181SM5JG |
| One-letter sequence | KTTKS |
| Three-letter sequence | Lys–Thr–Thr–Lys–Ser |
| Terminal groups | N-terminal palmitoylation; Free C-terminal carboxyl |
The peptide core is KTTKS, five L residues, with a palmitoyl group on the Lys1 alpha-amino group and a free Ser5 carboxyl, as encoded by PubChem CID 9897237. The palmitoyl group is recorded as a terminal modification, not as a residue, so the one-letter string shows the core only. Summing the five residues, removing four waters and adding the palmitoyl increment C16H30O gives C39H75N7O10 and 802.07 Da, reproducing the recorded formula.
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Structural characteristics
The palmitoyl group is a sixteen-carbon acyl chain attached at the N-terminus, and accounts for a substantial share of the molecular mass relative to the five-residue peptide core. PubChem CID 9897237 places palmitoyl on the Lys1 alpha-amino group and retains a free Ser5 carboxyl, distinguishing this structure from a lysine-side-chain-acylated positional isomer. The source review reports an in vitro basis for action on fibroblasts through stimulation of extracellular matrix synthesis, describing the reported stimulatory effect as specific to collagen types I and III and to fibronectin expression.
Terminal features: N-terminal palmitoylation, Free C-terminal carboxyl.
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Molecular targets & mechanisms
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Analytical considerations
The palmitoyl modification dominates the lipophilicity of the molecule and is part of its declared identity; an unmodified KTTKS preparation is a different substance with a different mass. The sequence contains no aromatic residues, so UV detection at 280 nm gives no useful chromophore response. The source review notes a surprising absence of in vitro skin penetration data in the published literature.
Disagreements and mix-ups
Points where sources disagree about this compound's identity, or where a name or form is easily confused with another, as noted in this record. The discrepancy register quotes the passage for each one.
Often mixed up · Name or substance
Palmitoyl pentapeptide-3 and palmitoyl pentapeptide-4Often mixed up · Name or substance
Matrixyl (palmitoyl-KTTKS) vs unmodified KTTKSAlso noted in KTTKS (Pentapeptide-4)
What the studies reported
Each finding describes one cited study in its stated model. These observations are specific to that study and do not establish effects in other settings.
Cell and tissue studies
Dermal skin extract and whole-skin homogenate from male CrlOri:SKH1-hr hairless mice
In dermal skin extract and whole-skin homogenate from male CrlOri:SKH1-hr hairless mice, the study measured pal-KTTKS remaining fractions of 9.7% after 120 min and 11.2% after 60 min, respectively.
Reference [3]Epidermal skin extract from male CrlOri:SKH1-hr hairless mice
In epidermal skin extract from male CrlOri:SKH1-hr hairless mice, the study observed pal-KTTKS concentrations remaining approximately similar to the initial concentration throughout a 120-min incubation.
Reference [3]Dermal skin extract and whole-skin homogenate from male CrlOri:SKH1-hr hairless mice
In dermal skin extract and whole-skin homogenate from male CrlOri:SKH1-hr hairless mice, the study reported significantly improved pal-KTTKS stability with protease inhibitors, while thimerosal showed no substantial protective effect.
Reference [3]Franz diffusion cells with full-thickness skin from male CrlOri:SKH1-hr hairless mice
In Franz diffusion cells with full-thickness skin from male CrlOri:SKH1-hr hairless mice, the study reported a trace pal-KTTKS signal in receptor solution after 24 h that remained below the assay quantitation limit.
Reference [3]
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Verified bibliography
Cited studies by type
The 5 papers this record cites, counted by the kind of work each reports. A count is the size of this record's selection, not of the research that exists, and says nothing about results, safety, effectiveness or approval.
A paper can report more than one kind of work. Each count opens those papers in the bibliography. Compare every record on the Evidence Map.
Reference 1
Topically applied KTTKS: a review.Abu Samah NH, Heard CM
International journal of cosmetic science · 2011-05-03 · Review
currentReference 2
A pentapeptide from type I procollagen promotes extracellular matrix production.Katayama K, Armendariz-Borunda J, Raghow R, Kang AH, Seyer JM
The Journal of biological chemistry · 1993-05-15 · Journal Article
currentReference 3
Dermal Stability and In Vitro Skin Permeation of Collagen Pentapeptides (KTTKS and palmitoyl-KTTKS).Choi YL, Park EJ, Kim E, Na DH, Shin YH
Biomolecules & therapeutics · 2014-07 · Journal Article
currentReference 4
Development of a LC-MS/MS method to monitor palmitoyl peptides content in anti-wrinkle cosmetics.Chirita RI, Chaimbault P, Archambault JC, Robert I, Elfakir C
Analytica chimica acta · 2009-03-20 · Journal Article
currentReference 5
Self-assembly of palmitoyl lipopeptides used in skin care products.Castelletto V, Hamley IW, Whitehouse C, Matts PJ, Osborne R, Baker ES
Langmuir : the ACS journal of surfaces and colloids · 2013-07-12 · Journal Article
current
Study models of these references
What kind of experiment each cited paper reports, taken from its abstract unless marked. Not a summary of results.
| Reference | Study models |
|---|---|
| Abu Samah NH et al. 2011 | Review article |
| Katayama K et al. 1993 | Study models reported: in vitro · from the abstract |
| Choi YL et al. 2014 | Study models reported: in vitro · from the abstract |
| Chirita RI et al. 2009 | Chemical, structural or analytical study; no biological model reported |
| Castelletto V et al. 2013 | Chemical, structural or analytical study; no biological model reported |
Compare
Record history
Published 2026-09-12.
- : Sequence and structure
- : References
Each entry names the parts of this record that changed on that date. Changes to links between records and to catalogue links are not listed. This history covers the tracked record fields; study findings are not listed here.
Cite this record: Purely Peptides Research Library. Matrixyl. Published 2026-09-12; updated 2026-10-14. https://purelypeptides.org/research/compounds/matrixyl/
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Methodology & citation verification
Reference identity is checked against official PubMed metadata. Local deterministic receipts bind each normalized title and canonical metadata record to its verification date. Scientific values remain absent when an authoritative source has not been verified.
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