Tetrapeptide-21

Tetrapeptide-21
Identifiers
	IUPAC name (4S)-4-[(2-aminoacetyl)amino]-5-[[(2S)-6-amino-1-(carboxymethylamino)-1-oxohexan-2-yl]amino]-5-oxopentanoic acid;
CAS Number	960608-17-7;
PubChem CID	42630677;
ChemSpider	32698920;
CompTox Dashboard (EPA)	DTXSID80242108 ;
Chemical and physical data
Formula	C15H27N5O7
Molar mass	389.409 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES C(CCN)C[C@@H](C(=O)NCC(=O)O)NC(=O)[C@H](CCC(=O)O)NC(=O)CN;
	InChI InChI=1S/C15H27N5O7/c16-6-2-1-3-9(14(26)18-8-13(24)25)20-15(27)10(4-5-12(22)23)19-11(21)7-17/h9-10H,1-8,16-17H2,(H,18,26)(H,19,21)(H,20,27)(H,22,23)(H,24,25)/t9-,10-/m0/s1; Key:CUVSTAMIHSSVKL-UWVGGRQHSA-N;

Tetrapeptide-21 (GEKG peptide) is a tetrapeptide that is derived from a sequence found in connective tissue proteins such as collagens and elastin. It stimulates endogenous biosynthesis of collagens, fibronectin and hyaluronic acid, and is used in skincare products for its purported anti-aging effects.^[1]^[2]^[3]^[4]

References

^ Farwick M, Grether-Beck S, Marini A, Maczkiewitz U, Lange J, Köhler T, et al. (July 2011). "Bioactive tetrapeptide GEKG boosts extracellular matrix formation: in vitro and in vivo molecular and clinical proof". Experimental Dermatology. 20 (7): 602–604. doi:10.1111/j.1600-0625.2011.01307.x. PMID 21692860.
^ Sommer E, Neubert RH, Mentel M, Tuchscherer B, Mrestani Y, Wohlrab J (November 2018). "Dermal peptide delivery using enhancer molecules and colloidal carrier systems. Part III: Tetrapeptide GEKG". European Journal of Pharmaceutical Sciences. 124: 137–144. doi:10.1016/j.ejps.2018.08.034. PMID 30165235.
^ Paccola AG, Santos TM, Minelo MC, Garbieri TF, Sanches ML, Dionísio TJ, et al. (August 2025). "Synergistic Effects of Injectable Platelet-Rich Fibrin and Bioactive Peptides on Dermal Fibroblast Viability and Extracellular Matrix Gene Expression: An In Vitro Study". Molecules. 30 (16): 3415. doi:10.3390/molecules30163415. PMC 12388378. PMID 40871567.
^ Stephenson H, Lim A, Dupuy R, Brun S, Armstrong A, Okunola N, et al. (December 2025). "Elastin-derived peptide hydrogels for sustained dermal delivery of tetrapeptide-21". International Journal of Pharmaceutics. 689 126490. doi:10.1016/j.ijpharm.2025.126490. hdl:10044/1/126629. PMID 41421628.