“Thicker fuller hair”
Fantastic products. Great quality. Highly recommend for anyone looking for thicker fuller hair!
Verified buyer
Copper Peptide Hair Tonic with AHK-Cu and Acetyl Tetrapeptide-3
Both Peptides Verified at 1% by a 3rd Party Lab
Key Benefits
Supports Hair at the Root
Supports Fuller-Looking Hair
Studied on Human Hair Follicles
Best for: making the tonic part of your daily routine, and the best value per day. Early changes typically start to show after 6 to 8 weeks of daily use and build with consistent use.
Discovery SizeBest for a first trial, to see how the tonic fits your routine. For visible changes, we recommend the Full Size. Early changes typically start to show after 6 to 8 weeks of daily use.
Choose your plan
Most popular · Save 15% on every order
- Free shipping on every order
- Pause, skip, or cancel anytime
- 30-day returns, even if you've opened it
Deliver every
8
weeks
Most subscribers choose every 8 weeks.
Heads up: at this interval you may run out before your next bottle arrives, based on typical daily use.
New to PLU? Use code START10 at checkout for 25% off your first subscription order.
Most popular · Save 15% on every order
- Free shipping on every order
- Pause, skip, or cancel anytime
- 30-day returns, even if you've opened it
Deliver every
3
weeks
Most subscribers choose every 3 weeks.
Heads up: at this interval you may run out before your next bottle arrives, based on typical daily use.
New to PLU? Use code START10 at checkout for 25% off your first subscription order.
Who this is for
- You've noticed thinning, a widening part, or a hairline starting to recede, and you want to act on it early.
- You want a simple five-ingredient formula with no DHT blockers, hormones, or fragrance.
- You can commit to once-a-day use and give it a few months. Early changes typically start around 6 to 8 weeks and build from there.
Who this isn't for
- You're expecting visible change in under 6 weeks. Peptides work gradually.
- You're looking for a one-bottle fix. Results come from consistent daily use over months, not a single bottle.
- You want a DHT blocker or a minoxidil alternative. This is neither. It's a scalp-support formula. Ask your dermatologist about using it alongside a treatment.
Third-Party Lab Verified
Made in the USA
Just 5 Ingredients
Never Tested on Animals
Made in the USA of domestic and internationally sourced components.
Nourish Your Hair With AHK-Cu Peptide
AHK-Cu peptide is a synthetic copper peptide (Copper Tripeptide-3) made to support the appearance of fuller-looking hair. Our copper peptide serum pairs it at 1% concentration with 1% Acetyl Tetrapeptide-3.
Two clinically studied peptides, five total ingredients. No fragrance, no dyes, no botanical extracts. Both peptides verified at 1% by LC-MS in the finished bottle, at or above label claim, at the University of Illinois at Chicago. Most serums list 20 or 30 ingredients. We made one with everything you need, and nothing you don't.
Bring out the full potential of your hair by making this serum a part of your routine.
Ships directly to the USA. Also available on amazon.com domestically and in select international markets.
AHK-Cu | Copper Peptide Hair Tonic for Fuller-Looking Hair
Sale price$119.99
Choose options
AHK-Cu | Copper Peptide Hair Tonic for Fuller-Looking Hair
Sale price$119.99
Best for: making the tonic part of your daily routine, and the best value per day. Early changes typically start to show after 6 to 8 weeks of daily use and build with consistent use.
PLU vs a typical hair serum
Compared
PLU
Typical hair serum
Ingredients on the label
5
20+
Named peptide actives
Yes
Varies
Concentrations disclosed
YesIndependently verified
Rarely
Finished bottle tested by an independent lab
Yes
Rarely
Public lab report
Yes
Rarely published
Filler actives
None
Common
PLU Copper Peptide Hair Tonic, 5 ingredients
- Water
- Glycerin
- Copper Tripeptide-3
- Acetyl Tetrapeptide-3
- Phenoxyethanol
See a typical hair serum's full ingredient list
- Aqua
- Butylene glycol
- Polyamino sugar condensate
- Panthenol
- Biota orientalis leaf extract
- Glycine soja (Soybean) germ extract
- Panax ginseng root extract
- Copper tripeptide-1
- Biotin
- Triticum vulgare (Wheat) germ extract
- Serenoa serrulata fruit extract
- Scutellaria baicalensis root extract
- Myristoyl pentapeptide-4
- Polyacrylate crosspolymer-6
- 1,2-Hexanediol
- Hydroxyacetophenone
- Sodium hyaluronate
- Peg-40 hydrogenated castor oil
- Allantoin
- Disodium EDTA
5
ingredients
2
peptide actives
30s
once-a-day routine
Independently Tested
Third-Party Lab Verified
Every formula is tested by the Mass Spectrometry Core at the University of Illinois at Chicago. Actives verified by LC-MS in the finished bottle, at or above label claim. Heavy metals screened by ICP-MS. Reports published.
Concentration (LC-MS)
Purity
Heavy Metals (ICP-MS)
See latest test results +
Real customers, real routines
Verified reviews from PLU customers
Five ingredients. Independently verified.
Every batch is third-party tested, and the report is published right on this page.
“No residue”
The product seems to absorb well and doesn't leave behind a residue.
Early access tester
“A month in”
Looking good so far! Only a month in and i see some progress.
Verified buyer
Thousands of orders shipped
Made in the USA. 30-day returns, even if you've opened it.
A
So far so good, only one month in. Will update after 2-3 months.
Hi there!
Thanks for sharing an update. Keep us posted on the results!
Best,
The PLU Laboratories Team
A
Looking good so far! Only a month in and i see some progress.
Hello!
Thanks for the kind review. We're thrilled to see you're seeing progress already. Keep us posted as you continue!
Cheers,
The PLU Laboratories Team
J
Hard to apply, no improvements
D
Fantastic products. Great quality. Highly recommend for anyone looking for thicker fuller hair!
David - thanks for the kind words. We hope you come back again soon!
Best,
The PLU Laboratories Team
P
Early results are promising, seeing baby hairs sprout up.
Peter,
Thanks for the review and glad to hear you're seeing the results you wanted!
Keep us posted.
Cheers,
The PLU Laboratories Team
R
Got this as a part of an early access program. The product seems to absorb well and doesn't leave behind a residue. Can't say that I've seen much in terms of results yet, but it's only been a few weeks. Will plan to update after I've used this for longer.
Hey there,
Thanks for the kind words! we're excited to see what this can do for you. Keep us posted as you progress!
Best,
The PLU Laboratories Team
R
Got this as a part of an early access program. The product seems to absorb well and doesn't leave behind a residue. Can't say that I've seen much in terms of results yet, but it's only been a few weeks. Will plan to update after I've used this for longer.
What you're putting on your scalp
Five ingredients, each with a job.
Two peptide actives at 1% each, and three ingredients to carry them and keep them stable.
5
-
1%Peptide active
AHK-Cu Copper Tripeptide-3
A copper peptide with an added alanine, for the look of scalp and hair. More on this CloseSits at a full 1%, the same concentration as the Acetyl Tetrapeptide-3 beside it, and the concentration is confirmed by an outside lab.
-
1%Peptide active
Acetyl Tetrapeptide-3
A biomimetic peptide, included for the appearance of hair density. More on this CloseIt sits at the same 1% as the AHK-Cu, so neither active is a dusting on the label.
-
Water
The base. Water based, so nothing sits on the scalp. More on this CloseNo oils and no silicones, which is why it absorbs in seconds and leaves nothing to rinse out.
-
Glycerin
A humectant. It carries the peptides and helps the scalp hold on to moisture. More on this CloseIt is the reason two or three drops spread across the part without leaving a film on the hair.
-
Phenoxyethanol
A gentle preservative, so what is in the bottle stays safe to use. More on this CloseOne preservative at a low level, the standard choice for water based cosmetics.
Ingredients (INCI)
Water, Glycerin, Copper Tripeptide-3, Acetyl Tetrapeptide-3, Phenoxyethanol
Independently verified. See the test results.What is not in it
- No fragrance
- No dyes
- No hormones
- No DHT-blocker gimmicks
- No botanical extracts
Why PLU
Verified, not claimed.
Just 5 ingredients. And a lab report to prove it.
Five ingredients, each with a job
AHK-Cu, Acetyl Tetrapeptide-3, water, glycerin, phenoxyethanol. Every one earns its place.
Tested in the finished bottle
1% AHK-Cu and 1% Acetyl Tetrapeptide-3 verified by LC-MS at the University of Illinois at Chicago, at or above label claim. Heavy metals screened by ICP-MS.
Read the lab reportsMade in the USA, 30-day returns
Formulated and produced domestically, with 30-day returns.
What is AHK-Cu?
AHK-Cu (Copper Tripeptide-3) is a synthetic variant of GHK-Cu. Both are copper peptides, but AHK-Cu swaps glycine for alanine in its amino acid chain (alanine-histidine-lysine vs glycine-histidine-lysine). Research on AHK-Cu has focused primarily on hair follicle applications.
We offer both GHK-Cu and AHK-Cu Hair Tonics so you can choose based on your preference. Same dual-peptide formula, same concentrations, same carrier system. The only difference is which copper peptide variant is used. Read our full AHK-Cu vs GHK-Cu comparison.
Supports Hair Appearance
AHK-Cu copper peptide supports scalp's natural processes for fuller-looking hair and improved density appearance
Fuller-Looking Hair
Acetyl Tetrapeptide-3 helps improve how hair appears with consistent use and follicle support
Scalp Health Support
Designed to help maintain healthy-looking scalp conditions and follicle appearance
Concentrations That Matter
Peptide concentrations formulated to match published research on hair appearance
What Can AHK Peptide Do For Your Hair and Skin?
The AHK peptide can be a powerful form of support for hair follicles. Studies suggest that AHK-Cu peptide may help promote the appearance of thicker, fuller-looking hair (when applied at clinical concentrations over time). The Acetyl Tetrapeptide-3 in our formula complements it. Most people see visible changes within 6-8 weeks of consistent daily use.
Some people also apply copper peptides for skin. AHK-Cu has early research interest there, but there’s just not as much data on that angle compared to GHK-Cu - which has decades of peer-reviewed study. Our GHK-Cu serum is the better fit for skin support. It pairs 1% GHK-Cu with Palmitoyl Tripeptide-1 and Palmitoyl Tetrapeptide-7. AHK peptide is built for your scalp.
Application Steps
1 Part
Works on dry or damp hair. Create sections to expose scalp.
2 Apply
Dispense directly onto scalp. Use fingertips to massage into areas of concern
3 Leave In
Do not rinse. Style hair as usual. Use morning and/or night.
Expected Progress
What to Expect From Our Copper Peptide Hair Serum
1-2
Weeks 1-2
Scalp feels healthier with improved comfort
3-4
Weeks 3-4
Hair appears smoother with improved shine
6-8
Weeks 6-8
Visible improvements in hair density and scalp health
8-12
Weeks 8-12
Hair appears noticeably thicker and fuller
12+
Weeks 12+
Ongoing support for fuller, denser hair with daily use
Individual results may vary. Research on copper peptides, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, and Acetyl Tetrapeptide-3 noted visible improvements within study timeframes with consistent use of peptide complexes.
GHK-Cu vs AHK-Cu
GHK-Cu supports scalp health, improving the environment your hair grows in. AHK-Cu is the copper peptide studied on hair follicles themselves, supporting the roots that grow each strand.
GHK-Cu
Studied for more than 30 years. Your body makes it naturally, and makes less of it with age. In lab studies it signals skin to produce collagen and elastin, the support structure of a healthy scalp.1
AHK-Cu
Less total research, but what exists was done directly on human hair follicles. In lab studies AHK-Cu supported follicle growth and the cells at the root of each hair.2
The research above is for the individual ingredients.
Which one?
GHK-Cu Hair Tonic
Supports scalp and overall hair health.
$79.99 or $67.99 with subscription
Shop GHK-Cu Hair TonicAHK-Cu Hair Tonic
The follicle-focused step-up, with the peptide studied on hair follicles.
$119.99 or $101.99 with subscription
Shop AHK-Cu Hair Tonic- Pickart L, Margolina A. Int J Mol Sci. 2018.
- Pyo HK et al. Arch Pharm Res. 2007.
- Loing E et al. J Cosmet Sci. 2013 (ingredient tested in a blend).
Who Is This For?
This is for you if...
- You've noticed thinning, a widening part, or a hairline starting to recede, and you want to act on it early.
- You want a simple five-ingredient formula with no DHT blockers, hormones, or fragrance.
- You can commit to once-a-day use and give it a few months. Early changes typically start around 6 to 8 weeks and build from there.
This isn't for you if...
- You're expecting visible change in under 6 weeks. Peptides work gradually.
- You're looking for a one-bottle fix. Results come from consistent daily use over months, not a single bottle.
- You want a DHT blocker or a minoxidil alternative. This is neither. It's a scalp-support formula. Ask your dermatologist about using it alongside a treatment.
Frequently Asked Questions
Is AHK-Cu better than GHK-Cu?
Not better, just different. Both are copper peptides with the same histidine-lysine-copper structure. AHK-Cu (Copper Tripeptide-3) swaps glycine for alanine in the amino acid chain. GHK-Cu occurs naturally in human plasma and has decades of research across skin and hair. AHK-Cu is a synthetic variant with research focused primarily on hair follicle applications. We carry both here at PLU Laboratories, and you can always read our full AHK-Cu vs GHK-Cu comparison if you want to learn more.
What are the benefits of AHK-Cu?
Research suggests it may help support the appearance of hair density and fullness when applied consistently. Our formula uses 1% AHK-Cu paired with 1% Acetyl Tetrapeptide-3 at clinical concentrations. Five ingredients total, with visible changes showing up within 6-8 weeks.
Is it safe to use AHK-Cu for hair?
Yes. Our formulation is free of parabens, sulfates, fragrance, and dyes. It's probably still worth patch testing on a small area first, as with any new scalp product. You may want to consult with a dermatologist before use if you have specific scalp concerns, too.
Where can I buy AHK-Cu peptide?
Right here at PLU Laboratories. Our AHK-Cu Hair Tonic comes in a 10 mL discovery size ($59.99) and a 30 mL full size ($119.99). We also carry copper peptides for hair in GHK-Cu formulations if you want to compare. Free shipping on every order.
How do I use AHK peptide?
Apply it directly to the scalp (not hair strands) since that’s where the formula needs to reach. Applying the copper peptide hair serum to strands will just leave you looking greasy without any actual impact on hair health. Massage it into the scalp for 30-60 seconds for best results. This may boost circulation and absorption. Focus on trouble areas.
From the PLU blog
Copper Peptides For Hair: Why Everyone is So Excited About GHK-Cu and AHK-Cu
It’s become impossible to ignore the hype around copper peptides for hair. But is it just that - hype? Or is there science behind copper peptides and hair? You’ve come to the right place. The short...
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Azelaic Acid and Copper Peptides: Can You Use Them Together?
Azelaic acid and copper peptides are compared all the time. But they do very different things. So can you use copper peptides and azelaic acid together in the same routine? Yes! Azelaic acid can he...
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Matrixyl 3000 vs Copper Peptides
Matrixyl 3000 vs copper peptides - a comparison we see play out in forums online all the time. But most people assume you have to pick one or the other. That’s not necessarily true. You may find th...
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