GHK-Cu Copper Peptide
Hair Growth via VEGF Pathways, 2023 (PMC10643103)
Significant increase in hair regrowth via VEGF pathway activation, with denser growth than control groups.
Read Study →Inside the Lab: PLU’s Science & Skincare Insights
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Copper Peptides For Rosacea: Does GHK-Cu Help With Rosacea?
Living with rosacea means wondering what’ll cause your next flare-up. So often, the very products you choose to help keep your skin feeling calm can backfire and cause more harm than good. This is...
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Copper Peptides For Scalp: Is a Copper Peptide Scalp Treatment Worth It?
Most people forget that the scalp is skin, which is why using copper peptides for scalp health is so powerful. These little messenger molecules can help encourage healthy hair growth by creating th...
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GHK-Cu for Loose Skin: Does GHK-Cu Help With Loose Skin?
Whether you lost a ton of weight and now have saggy skin or you’ve just noticed that age has cost you the firmness your skin used to have, it can take a toll on your self-confidence. The good news ...
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What Are the Best Topical Peptides? Top 7 Formulas in 2026
Whether you’re looking for the best topical peptides for skin or hair, your search ends here. We’ve handpicked the top products on the market backed by real results and value for the money, so you ...
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Peer-Reviewed Research
Clinical Studies & Research
Peer-reviewed studies backing each of our four key actives.
Palmitoyl Tripeptide-1 & Palmitoyl Tetrapeptide-7
Schagen, S. K. Topical Peptide Treatments with Effective Anti-Aging Results. Cosmetics, 2017, 4(2), 16.
Peer-reviewed review concluding that this palmitoyl peptide combination delivers measurable wrinkle depth reduction, increased collagen synthesis, and dermal density improvement comparable to retinoids, without the irritation.
Read Study →Acetyl Tetrapeptide-3
Acetyl Tetrapeptide-3 vs Minoxidil Comparison, 2020 (PMC7840088)
Increased anagen/telogen hair ratio and outperformed 3% Minoxidil in density metrics, with no observed irritation.
Read Study →AHK-Cu Copper Tripeptide
Pyo et al. Effect of tripeptide-copper complex on human hair growth in vitro. Arch. Pharm. Res., 2007.
Stimulated elongation of human hair follicles, increased dermal papilla cell proliferation, and reduced apoptotic cell death through Bcl-2/Bax pathway regulation.
Read Study →
Shop the tonics
Three focused formulas
Two peptides each. Everything you need, nothing you don't.
Face Tonic
Best forFine lines and skin firmness appearance
Actives1% GHK-Cu, plus palmitoyl peptides
RoutineUnder 30 seconds, morning and/or night
GHK-Cu Hair Tonic
Best forFuller-looking hair and scalp health
Actives1% GHK-Cu, 1% Acetyl Tetrapeptide-3
RoutineUnder 30 seconds, once a day, leave in
AHK-Cu Hair Tonic
Best forTargeted support for hair density appearance
Actives1% AHK-Cu, 1% Acetyl Tetrapeptide-3
RoutineUnder 30 seconds, once a day, leave in
Verified Customers
Real Results from Real Customers
★★★★★
Customers love the visible results from PLU's dual-peptide formulations
Face Tonic
★★★★★
"I've only been using this a week and I already see an improvement in my fine lines. It's rare to see noticeable change after that short time period with any product. I also started using it on my neck and the back of my hands. This stuff is amazing."
Hair Tonic
★★★★★
"I purchased the tonic to improve hair growth and to counteract thinning near the top of my head. Since then, I have visibly improved coverage, materially less shedding, and an excess of confidence. My old lady even noticed and questioned if my stylist had tried something new!!"
Face Tonic
★★★★★
"AWESOME. Only a week in. Skin looks younger and confidence is oozing. New level of aura unlocked."
Hair Tonic
★★★★★
"This hair tonic doesn't leave any residue or mess like minoxidil does. Even though I've only used it for about a month, I can already feel my hair getting healthier and fuller."
Why PLU
Verified, not claimed.
Working peptides, simple carriers, and an independent lab report behind every formula.
Six ingredients or fewer
Five ingredients in the Hair Tonic, six in the Face Tonic. Every one earns its place.
Tested in the finished bottle
Every active verified by LC-MS at the University of Illinois at Chicago, at or above label claim. Heavy metals screened by ICP-MS.
Made in the USA, 30-day returns
Formulated and produced domestically, backed by a 30-day money-back guarantee.
Frequently Asked Questions About Peptide Science
What makes PLU Laboratories' peptide formulations different?
PLU Laboratories focuses on multi-peptide systems at clinically studied concentrations, verified by LC-MS in the finished product at the University of Illinois at Chicago. Most peptide products contain either GHK-Cu or other peptides, rarely both, and very few publish a finished-product test. Our approach combines complementary peptide technologies: GHK-Cu + Palmitoyl Tripeptide-1 & Palmitoyl Tetrapeptide-7 for skin, or GHK-Cu + Acetyl Tetrapeptide-3 for hair.
Why don't PLU products include hyaluronic acid or vitamin C?
We keep each formula to the peptides and their carriers. That keeps the peptide concentrations where we verify them and leaves the rest of your routine up to you. Hyaluronic acid and vitamin C are good ingredients; apply them after the peptides absorb, at whatever strength you prefer.
What concentrations of peptides does PLU use?
Many brands use trace amounts of peptides, just enough to list on the label. Our formulations use peptide concentrations aligned with those examined in published research studies.
Our GHK-Cu Face Tonic contains 1% GHK-Cu, plus raw Palmitoyl Tripeptide-1 and Palmitoyl Tetrapeptide-7, dosed to the levels a 3% Matrixyl 3000 solution delivers. We buy the peptides themselves rather than the pre-diluted blend, so none of its carbomer, polysorbate 20, or butylene glycol comes along with them. Our GHK-Cu Hair Tonic contains 1% GHK-Cu and 1% Acetyl Tetrapeptide-3.
What is the research behind Acetyl Tetrapeptide-3 for hair?
Clinical studies on Acetyl Tetrapeptide-3 examined this biomimetic peptide for supporting hair density appearance. Research suggests it works by strengthening extracellular matrix proteins around hair follicles.
In trials, it outperformed 3% Minoxidil in density metrics. Our GHK-Cu Hair Tonic combines this with GHK-Cu at the concentrations studied in the literature.
What timeline should I expect for visible results?
Clinical studies typically measured improvements over 6-12 weeks. Most users report smoother skin or healthier-looking scalp in 1-2 weeks, with notable appearance improvements in skin firmness or hair density by weeks 6-8.
Individual results may vary. These timeframes align with the protocols used in published peptide efficacy studies.
Can I use other active ingredients with PLU products?
Yes. Apply PLU peptides first on clean skin, wait for absorption, then layer other actives or moisturizers as desired to maintain research-aligned efficacy.
For specifics on layering with common actives, see our deep dives on copper peptides and vitamin C, copper peptides and retinol, and GHK-Cu vs tretinoin.