GHK-Cu

Properties

Full name glycyl-L-histidyl-L-lysine copper(II) source
Inci name Copper Tripeptide-1 source
Cas number 89030-95-5 source
Unii 6BJQ43T1I9 source
Molecular formula C14H22N6O4.Cu (equivalently C14H22CuN6O4) source
Molecular weight 401.91 g/mol source
Appearance Crystallised from aqueous copper(II) acetate with ethanol it forms dark purple-blue octahedral crystals; in column purification the complex is collected as the elution peak absorbing at 600 nm. Stated under the cosmetic safety review's Method of Manufacture heading for copper tripeptide-1, so it describes the copper complex rather than the uncomplexed peptide. The underlying source is Pickart and Lovejoy, Methods in Enzymology 1987. source
Solubility Highly hydrophilic. Octanol / phosphate-buffered-saline distribution coefficients (log D) measured between -2.38 and -2.49 across the pH range 4.5 to 7.4. source
Storage This is an accelerated stability finding, not a handling instruction. Under forced-degradation testing the complex remained stable in water and in pH 4.5 to 7.4 buffers held at 60 degrees C for at least two weeks, while basic and oxidative stressors, and to a lesser extent acidic stress, caused hydrolytic cleavage with first-order degradation profiles. A 60 degrees C challenge is a stress condition used to measure degradation kinetics; it is not a holding temperature, and the published literature does not establish one. source
Cosmetic function Skin conditioning agent. The cosmetic safety review assigns this function collectively to the ingredients it covers, copper tripeptide-1 among them, rather than determining it for copper tripeptide-1 individually. source
Cosmetic use concentration The cosmetic safety review states typical use concentrations of less than 10 ppm. That figure is given collectively for the ingredients the review covers and traces to an industry submission describing customary use for peptides generally; it is not a measurement specific to copper tripeptide-1. source
Surveyed use concentration range A Personal Care Products Council survey conducted in 2013 and updated in 2014 reported use concentrations ranging from 0.0000001% to 0.002% across the peptide ingredients covered by the review. The range is collective across those ingredients rather than specific to copper tripeptide-1, and the upper figure relates to leave-on products. source
Starting material purity This figure describes tripeptide-1 (GHK), the uncomplexed peptide GHK-Cu is made from, and not GHK-Cu itself. Under its Composition/Impurities heading for tripeptide-1 (GHK), the cosmetic safety review describes commercial glycyl-L-histidyl-L-lysine as approximately 95% pure, often including small amounts of mildly neurotoxic material that can be reduced by dissolution in glass-distilled water, centrifugation, and lyophilisation of the supernatant. That review's Composition/Impurities section carries no entry for copper tripeptide-1. Its later summary section does restate the figure as applying to GHK-Cu2+, contradicting its own body text; the body attribution is the one followed here. The underlying source is Pickart and Lovejoy, Methods in Enzymology 1987. source
Safety review The Cosmetic Ingredient Review Expert Panel concluded that copper tripeptide-1 is safe in the present practices of use and concentration in cosmetics. source
Plasma concentration Reported at about 200 ng/mL of plasma at age 20, declining to about 80 ng/mL by age 60. Figures are from a narrative review, not from a primary measurement study. source

What the research does not show

Storage and handling

This is an accelerated stability finding, not a handling instruction. Under forced-degradation testing the complex remained stable in water and in pH 4.5 to 7.4 buffers held at 60 degrees C for at least two weeks, while basic and oxidative stressors, and to a lesser extent acidic stress, caused hydrolytic cleavage with first-order degradation profiles. A 60 degrees C challenge is a stress condition used to measure degradation kinetics; it is not a holding temperature, and the published literature does not establish one. source

Concentration calculator · Research index · Reading a certificate of analysis