Frequently Asked Questions

GHK-Cu (copper tripeptide-1) is a naturally occurring copper peptide consisting of three amino acids (glycine, histidine, lysine) bound to copper ions. The NIH research describes GHK-Cu as functioning both as a signal peptide (communicating with dermal fibroblasts and skin cells) and as a carrier peptide (delivering copper ions studied for collagen production pathways).

This dual function differentiates copper peptides from other amino acid complexes like Matrixyl 3000 (matrikine signal peptides) or Acetyl Tetrapeptide-3 (biomimetic follicle-support peptides). The best formulations combine GHK-Cu with complementary peptides rather than diluting with hyaluronic acid or vitamin C. Our best copper peptide serum guide explains dual-peptide systems in detail.

The clinical research on GHK-Cu examined this copper peptide as a signal and carrier peptide complex, not diluted with hyaluronic acid, vitamin C, or other non-peptide actives in the same formulation. Adding these ingredients reduces the peptide concentrations studied in published literature and may interfere with copper peptide stability.

Our Face Tonic and Hair Tonic maintain GHK-Cu concentrations examined in research by combining with complementary peptides (Matrixyl 3000 for skin, Acetyl Tetrapeptide-3 for hair) rather than non-peptide actives. If you want hyaluronic acid or vitamin C, apply them separately after the peptides absorb to maintain peptide efficacy.

Clinical research suggests GHK-Cu may support hair density appearance through its influence on hair follicle biology and scalp health. Studies indicate this copper peptide may help create a healthier-appearing scalp environment through tissue processes and scalp circulation appearance.

For optimal hair appearance support, our copper peptide hair serum combines GHK-Cu with Acetyl Tetrapeptide-3, creating a dual-peptide system where copper peptides support scalp health while biomimetic peptides target follicle-level anchoring. This combination addresses hair appearance through complementary mechanisms studied in published research. Explore our complete copper peptides for hair collection.

Matrixyl 3000 is a specific dual-peptide complex requiring both Palmitoyl Tripeptide-1 AND Palmitoyl Tetrapeptide-7 working together. Research describes these as matrikine signaling peptides studied for fine lines appearance and skin texture. Many peptide serums contain only one of these peptides or other peptides entirely, missing the synergistic benefits of the complete Matrixyl 3000 complex.

Our Face Tonic includes complete Matrixyl 3000 combined with GHK-Cu copper peptides, creating a comprehensive dual-peptide system studied in published literature. Learn more about our Matrixyl 3000 products and why this represents the best copper peptide serum approach.

Matrixyl 3000 and GHK-Cu work through different mechanisms studied in clinical research. The NIH research describes GHK-Cu as signal and carrier peptides studied for tissue processes and collagen production pathways. Matrixyl 3000 research focuses on matrikine signaling peptides examined for fine lines appearance and skin texture.

The best approach combines BOTH peptide technologies, creating a comprehensive system where copper peptides and matrikine peptides work through complementary amino acid pathways studied in published literature. This is why our copper peptide face serum includes both GHK-Cu and complete Matrixyl 3000 at clinical concentrations. Explore our complete copper peptides for skin collection.

Acetyl Tetrapeptide-3 is a biomimetic peptide extensively studied for supporting hair follicle structure and hair density appearance. Research suggests it works by targeting the dermal papilla (the foundation of hair follicles) to support hair anchoring and scalp health through cellular signaling mechanisms.

Unlike DHT blockers that work through hormonal pathways, Acetyl Tetrapeptide-3 mimics natural cellular processes studied in clinical literature. Our Hair Tonic combines Acetyl Tetrapeptide-3 with GHK-Cu copper peptides, creating a dual-peptide system for comprehensive hair appearance support. Learn more about our men's hair tonic approach.

Most copper peptide serums contain only GHK-Cu, missing the opportunity to combine complementary peptide technologies studied through different research pathways. The NIH examined GHK-Cu as signal and carrier peptides for tissue processes, while Matrixyl 3000 research studied matrikine signal peptides for fine lines, and Acetyl Tetrapeptide-3 research examined biomimetic peptides for follicle support.

Combining these complementary amino acid technologies creates a comprehensive system where multiple peptide complexes work through distinct mechanisms studied in clinical literature. This dual-peptide approach addresses multiple concerns (skin firmness, fine lines, hair density, scalp health) through complementary pathways. Explore our complete copper peptide products collection and copper peptide serum formulations.

Face Tonic: Apply 2-3 drops to clean, dry facial skin once daily. The dual-peptide system (GHK-Cu + Matrixyl 3000) absorbs quickly. If desired, layer hyaluronic acid or moisturizer after the peptides absorb.

Hair Tonic: Apply 2-3 drops to clean, towel-dried scalp once daily. Gently massage to support absorption. The dual-peptide system (GHK-Cu + Acetyl Tetrapeptide-3) works without rinsing.

Both products take under 30 seconds each to apply. For comprehensive peptide support across face and scalp, use both daily. Explore our face serum for men and men's hair tonic collections for more guidance.

Yes, but apply them separately. Research suggests GHK-Cu works best when not diluted with other active ingredients in the same formulation. Apply our copper peptide products (Face Tonic or Hair Tonic) to clean skin or scalp first. The dual-peptide systems absorb quickly, allowing you to layer hyaluronic acid, vitamin C, or moisturizer afterward if desired.

This approach maintains the peptide concentrations studied in research while providing flexibility for additional actives. When combining with retinoids, many users alternate application nights. Learn more on our best copper peptide serum guide.

Clinical studies suggest peptide appearance benefits develop gradually over 6-12 weeks of consistent use. Some users notice improvements in skin feel or scalp comfort within 2-4 weeks, with more visible changes in skin firmness appearance or hair density appearance usually evident by 6-8 weeks.

Our dual-peptide formulations combine complementary peptides (Matrixyl 3000 + GHK-Cu for skin, Acetyl Tetrapeptide-3 + GHK-Cu for hair) at clinical concentrations. Most users report visible improvements within research timeframes when applying once daily. Individual results vary based on starting condition and application consistency.

Clinical research examines specific concentrations: GHK-Cu at 0.5-2%, Matrixyl 3000 at 3-8%, and Acetyl Tetrapeptide-3 at 0.5-2%. Studies suggest that 1% GHK-Cu, 3% Matrixyl 3000, and 1% Acetyl Tetrapeptide-3 provide optimal balance between efficacy and tolerance.

Our Face Tonic contains 1% GHK-Cu + 3% complete Matrixyl 3000, while our Hair Tonic contains 1% GHK-Cu + 1% Acetyl Tetrapeptide-3. Both maintain the concentrations studied in research without diluting with non-peptide actives. Explore our GHK-Cu products collection.

Research suggests peptides are generally well-tolerated across different skin and hair types due to their amino acid-based mechanisms. Our products focus on peptide delivery for appearance support rather than addressing specific skin type concerns like oiliness or dryness.

The dual-peptide systems support skin texture appearance, fine lines, hair density appearance, and scalp health across various types. If you have dry skin needing extra hydration, layer hyaluronic acid or moisturizer after peptides absorb. The lightweight formulations work efficiently without heavy residue. Learn more about our approach for copper peptides for skin and copper peptides for hair.

We process and ship orders within 2 business days of receipt. You'll receive tracking information via email once your order ships.

Shipping Timeframes:

• Processing: 1-2 business days
• Domestic Shipping: 3-5 business days after processing
• Tracking: Provided automatically via email

Orders placed on weekends or holidays will be processed the next business day.

Currently, we ship within the United States only. We're working on expanding international shipping options. Contact us at productteam@plulaboratories.com if you have questions about future international availability.

You'll receive tracking information via email automatically once your order ships. The email includes a tracking number and link to monitor your shipment's progress. If you haven't received tracking within 2 business days of ordering, contact us at productteam@plulaboratories.com.

We accept returns of unopened, unused products within 30 days of delivery. To maintain product integrity and safety, we cannot accept returns of opened or used items.

Return Requirements:

• Product must be unopened and unused
• Original packaging intact
• Returned within 30 days of delivery
• Proof of purchase required

Contact us at productteam@plulaboratories.com with your order number and reason for return. We'll provide return instructions and a prepaid shipping label.

Refunds are processed within 5-7 business days of receiving your returned item. Once processed, the refund will appear in your original payment method within 3-5 business days, depending on your bank or card issuer.

You'll receive an email confirmation once your refund has been processed. If you have questions about your refund status, contact us at productteam@plulaboratories.com.

If you have questions about a product after receiving your order, or if you experience any issues with your purchase, we're here to help. Our product team can provide guidance on usage, answer formulation questions, or address any concerns.

We're committed to ensuring you have a positive experience with our science-backed formulations. Contact us at productteam@plulaboratories.com for assistance.

Yes, we can facilitate exchanges for unopened, unused products. Contact us at productteam@plulaboratories.com with your order number and which product you'd like to exchange to. We'll provide instructions and arrange the exchange.

If you're unsure which product is right for you, our team can help. Our Face Tonic combines GHK-Cu with Matrixyl 3000 for skin appearance, while our Hair Tonic combines GHK-Cu with Acetyl Tetrapeptide-3 for hair appearance.

PLU Laboratories focuses on dual-peptide systems at clinical concentrations without filler ingredient dilution. Most peptide serums contain either GHK-Cu OR other peptides, and many dilute peptides with hyaluronic acid, vitamin C, or botanical extracts.

Our approach combines complementary peptide technologies studied through different research pathways: GHK-Cu (signal and carrier peptides) + Matrixyl 3000 (matrikine signal peptides) for skin, or GHK-Cu + Acetyl Tetrapeptide-3 (biomimetic peptides) for hair. This dual-peptide approach maintains the concentrations examined in clinical research. Learn more about our formulation philosophy on our best copper peptide serum guide.

Our products are cosmetics regulated by FDA cosmetic rules, focused on appearance benefits. Clinical studies generally show peptides are well-tolerated in cosmetic formulations. However, individual sensitivities can vary, and we recommend patch testing any new product.

If you have concerns about ingredient compatibility with existing skin or scalp conditions, consult healthcare providers before use. Always discontinue use if persistent irritation occurs. For specific questions about our formulations, contact us at productteam@plulaboratories.com.

Absolutely. The research on GHK-Cu, Matrixyl 3000, and Acetyl Tetrapeptide-3 applies equally across genders. While we position our products for men in marketing (emphasizing efficiency and science-backed results), the dual-peptide formulations work through peptide mechanisms that support skin and hair appearance regardless of gender.

Our face serum and hair tonic deliver comprehensive peptide support in under 30 seconds daily, making them efficient for anyone interested in evidence-based skincare using peptide concentrations studied in clinical research.

PLU Laboratories sells cosmetic products, not FDA-approved drugs, so we cannot make claims about treating conditions or affecting body structure or function. However, extensive published research examines peptides for their cosmetic appearance benefits.

The NIH research describes GHK-Cu as a copper peptide studied for tissue processes and collagen production pathways. Clinical studies examined Matrixyl 3000 for fine lines appearance and Acetyl Tetrapeptide-3 for hair density appearance. Our products use these peptides at concentrations studied in research for cosmetic use to support skin firmness appearance, skin texture, hair density appearance, and scalp health with consistent application. Individual results may vary.

Store products in a cool, dry place away from direct sunlight and heat. Peptides are sensitive to temperature extremes and light exposure, which can affect stability. Keep bottles tightly closed when not in use.

Avoid storing in bathrooms where temperature and humidity fluctuate. For optimal peptide stability, store at room temperature (60-75°F) in a dark cabinet or drawer. Our formulations are designed to maintain peptide activity throughout the product shelf life when stored properly.

We publish educational articles examining the clinical research behind copper peptides, Matrixyl 3000, and other amino acid complexes studied for skin and hair appearance. Each article explores published studies, formulation approaches, and the science that informs our dual-peptide systems.

Visit our blog to read about GHK-Cu research from the NIH, Matrixyl 3000 mechanisms, and Acetyl Tetrapeptide-3 studies. All content focuses on peer-reviewed research and evidence-based cosmetic science. Explore our complete copper peptide serum collection to see how we apply this research.