Frequently Asked Questions

Everything you want to know about Serum Scientist, our science, our products, and your skin.

About Serum Scientist

What is Serum Scientist?

Serum Scientist is a premium, science-backed skincare brand built on the principles of longevity and regenerative science. We curate clinically validated actives — PDRN, copper peptides, ceramides, retinol, hyaluronic acid, niacinamide, exosomes, NMN, EGCG, and more — and make them accessible at real-world price points. Our mission: bridge the gap between the laboratory and your bathroom shelf.

What makes Serum Scientist different from other skincare brands?

We don't follow trends — we follow data. Every product is selected based on peer-reviewed clinical evidence. We are education-forward, transparency-driven, and committed to making medical-grade actives accessible without the medical-grade price tag. We also publish our Science Journal — a growing library of research-backed articles — so you can read the same science we do.

Where is Serum Scientist based?

Serum Scientist is a US-based direct-to-consumer brand operating at serumscientist.com.

Who founded Serum Scientist?

Serum Scientist was founded by Robert Lee — a researcher by passion and a survivor by grace. After navigating serious health challenges including a broken neck, broken back, two heart attacks, and eight stents, Robert developed a deep obsession with what the biology actually says about healing and longevity. That obsession became SerumScientist.com. Read the full story here.

Is Serum Scientist a new brand?

Yes — and we say that with pride, not apology. We came into this industry to change it. As a growing brand, we know we have to earn every star, every review, and every repeat order. We welcome that challenge.

Do you have a physical store?

We are currently online-only at serumscientist.com. This allows us to keep overhead low and pass the savings directly to you in the form of better pricing on premium actives.

Ingredients & Science

What is PDRN and why is it in your products?

PDRN (Polydeoxyribonucleotide) is a biotech-derived DNA fragment clinically shown to stimulate tissue repair, reduce inflammation, and support collagen synthesis. It activates A2A adenosine receptors, triggering a cascade of regenerative cellular activity. It is used in medical aesthetics worldwide and is one of our hero actives for anti-aging and barrier recovery protocols.

What are copper peptides (GHK-Cu)?

GHK-Cu is a naturally occurring copper peptide complex that stimulates collagen and elastin synthesis, promotes skin remodeling, and supports wound repair. It is one of the most studied anti-aging compounds in existence, with decades of peer-reviewed research behind it. It also has antioxidant and anti-inflammatory properties that make it exceptionally well-tolerated.

What are exosomes and what do they do for skin?

Exosomes are nano-sized extracellular vesicles that carry proteins, lipids, and genetic signals between cells. In skincare, they act as biological messengers — delivering regenerative instructions that accelerate repair, reduce inflammation, and stimulate collagen production. They represent the next frontier of regenerative aesthetics.

What is NMN and how does it relate to skin?

NMN (Nicotinamide Mononucleotide) is a direct precursor to NAD+, a coenzyme essential for cellular energy metabolism, DNA repair, and longevity signaling. As NAD+ levels decline with age, skin cells lose their regenerative capacity. NMN supplementation — topical and systemic — is an active area of longevity research.

What is EGCG?

EGCG (Epigallocatechin Gallate) is the primary bioactive polyphenol in green tea. It has potent antioxidant, anti-inflammatory, and photoprotective properties, and has been studied for its role in reducing UV-induced damage, inhibiting matrix metalloproteinases (enzymes that break down collagen), and supporting skin barrier function.

What are senolytics?

Senolytics are compounds that selectively clear senescent cells — sometimes called "zombie cells" — that have stopped dividing but remain metabolically active, secreting inflammatory signals (the SASP: Senescence-Associated Secretory Phenotype) that accelerate tissue aging. Clearing these cells reduces the inflammatory burden on surrounding healthy tissue.

What does niacinamide do?

Niacinamide (Vitamin B3) regulates sebum, minimizes pores, reduces inflammation, brightens uneven tone, and strengthens the skin barrier by increasing ceramide synthesis. It is one of the most well-tolerated actives available and layers beautifully with most other ingredients — including retinol, peptides, and vitamin C.

What does azelaic acid do?

Azelaic acid is a dicarboxylic acid with antibacterial, anti-inflammatory, and tyrosinase-inhibiting properties. It is clinically proven to reduce rosacea, acne, and post-inflammatory hyperpigmentation. It is safe for use during pregnancy (consult your provider) and is one of the most versatile brightening actives available.

Is retinol safe to use every day?

Retinol is one of the most clinically validated actives in skincare, but it requires an adjustment period. Start 2–3 times per week at night, always followed by SPF in the morning. Sensitive skin types should begin with a lower concentration and build gradually. Never use retinol with high-dose exfoliating acids in the same application.

What is the difference between retinol and tretinoin?

Tretinoin (retinoic acid) is a prescription-strength retinoid that binds directly to retinoic acid receptors. Retinol is an over-the-counter precursor that must be converted by the skin into retinoic acid — making it gentler but slower-acting. Both are clinically validated; the right choice depends on your skin's tolerance and your dermatologist's guidance.

What is hyaluronic acid and how does it work?

Hyaluronic acid (HA) is a naturally occurring glycosaminoglycan capable of holding up to 1,000x its weight in water. Multi-weight HA formulations deliver hydration at multiple skin depths — low molecular weight HA penetrates deeper, while high molecular weight HA forms a hydrating film on the surface. It is suitable for all skin types and all ages.

What are ceramides and why do they matter?

Ceramides are lipid molecules that make up approximately 50% of the skin's barrier (the stratum corneum). They act as the "mortar" between skin cells, preventing transepidermal water loss (TEWL) and protecting against environmental aggressors. Ceramide depletion is a primary driver of dry, sensitive, and reactive skin.

Do your products contain parabens, sulfates, or artificial fragrances?

No. We formulate without parabens, sulfates, or synthetic fragrances. Our focus is on functional actives, not masking agents.

Are your products cruelty-free and vegan?

All products are cruelty-free. Some formulations contain biotech-derived ingredients of biological origin (such as PDRN, which is salmon-derived). Product pages specify whether a product is fully vegan.

Are your products dermatologist-tested?

Our formulations are developed with input from cosmetic chemists and reviewed against current dermatological literature. We recommend patch-testing any new product before full application, especially if you have sensitive or reactive skin.

Routines & Stacking

How do I build a routine with your products?

Apply thinner, water-based serums first, then thicker formulations, and finish with SPF in the morning. A general layering order: cleanser → toner/essence → water-based serum → oil-based serum → moisturizer → SPF (AM only). Our Science Journal has detailed stacking guides for every active we carry.

What routine do you recommend for beginners?

Can I use multiple actives at the same time?

Many of our actives are designed to be layered. Some combinations require care — high-dose retinoids and exfoliating acids should not be used simultaneously. Copper peptides and vitamin C are best used at different times of day. Each product page and Science Journal article includes "Stack It With / Don't Stack It With" guidance.

Can I use PDRN and retinol together?

Yes — PDRN is an excellent pairing with retinol. Apply PDRN first to support barrier integrity and cellular repair, then layer retinol on top. PDRN's regenerative properties can help buffer retinol's initial adjustment period.

Can I use copper peptides and vitamin C together?

Not in the same application. Copper peptides and ascorbic acid (vitamin C) can interact and reduce each other's efficacy. Use vitamin C in the morning and copper peptides in the evening for best results.

How long before I see results?

Can I use your products with my existing skincare?

In most cases, yes. If you are using prescription actives such as tretinoin or topical antibiotics, we recommend consulting your dermatologist before adding new biotech actives to your routine.

Do I need to use SPF with your products?

Yes — always. Many actives (especially retinol, AHAs, and vitamin C) increase photosensitivity. SPF is non-negotiable in any evidence-based skincare routine. It is the single most validated anti-aging intervention available.

Skin Types & Concerns

Which products are best for dry skin?

Prioritize ceramide-rich moisturizers, multi-weight hyaluronic acid serums, and PDRN for barrier repair. Avoid over-exfoliating. Focus on occlusive and emollient ingredients that lock in moisture and rebuild the lipid barrier.

Which products are best for oily or acne-prone skin?

Niacinamide is your best friend — it regulates sebum and reduces inflammation without stripping the skin. Azelaic acid addresses both acne and post-inflammatory hyperpigmentation. Lightweight, non-comedogenic formulations are key. Avoid heavy occlusives that can clog pores.

Which products are best for sensitive or reactive skin?

Start with ceramides, PDRN, and niacinamide — all are exceptionally well-tolerated. Introduce one new active at a time and patch test before full application. Avoid high-dose retinol, exfoliating acids, and vitamin C until your barrier is strong and stable.

Which products are best for mature or aging skin?

Focus on collagen-stimulating actives: GHK-Cu, PDRN, retinol, and peptides. Layer with ceramides for barrier support and hyaluronic acid for plumping hydration. Exosomes and NMN are emerging actives with strong longevity-science rationale for mature skin.

Which products are best for hyperpigmentation?

Niacinamide, azelaic acid, and vitamin C are the most clinically validated brightening actives. Retinol accelerates cell turnover, helping to fade dark spots over time. Consistent SPF use is essential — UV exposure is the primary driver of hyperpigmentation.

Can men use your products?

Absolutely. Skin biology is skin biology. All of our products are formulated for efficacy, not gender. Men's skin tends to be thicker and oilier, which may affect how quickly certain actives are absorbed — but the mechanisms and benefits are identical.

Are your products suitable for all ages?

Yes, with appropriate active selection. Younger skin (20s–30s) benefits most from prevention — SPF, antioxidants, and barrier support. Mature skin (40s+) benefits from collagen-stimulating actives like retinol, GHK-Cu, and PDRN. Our Science Journal includes age-specific protocol guidance.

Safety & Sensitivities

How do I patch test a new product?

Apply a small amount of the product to the inside of your wrist or behind your ear. Wait 24–48 hours and observe for redness, itching, or irritation. If no reaction occurs, proceed with full application. Always introduce one new active at a time so you can accurately identify any reactions.

Can I use your products while pregnant or breastfeeding?

We recommend consulting your healthcare provider before introducing any new skincare actives during pregnancy or breastfeeding. Retinoids (including retinol) are generally contraindicated during pregnancy. Niacinamide, ceramides, and hyaluronic acid are widely considered safe, but always defer to your provider.

I'm experiencing redness or irritation. What should I do?

Discontinue the new active immediately and return to a simple barrier-support routine: gentle cleanser, ceramide moisturizer, and SPF. Allow your skin to recover for 1–2 weeks before reintroducing any actives. If irritation persists, consult a dermatologist.

Are your products safe for use around the eyes?

The eye area has thinner, more delicate skin. Avoid applying high-dose retinol or exfoliating acids directly to the orbital area. Peptide-based and ceramide-based formulations are generally safe for the eye contour. Always check individual product guidance.

Can I use your products if I have eczema or rosacea?

Many of our formulations are designed with compromised barriers in mind. PDRN, ceramides, and niacinamide are all well-tolerated by eczema and rosacea-prone skin. Avoid actives that generate heat or increase vasodilation (such as high-dose niacin or strong exfoliants). Consult your dermatologist for personalized guidance.

Are your products safe for use after professional treatments (laser, microneedling, peels)?

PDRN and ceramide-based formulations are excellent post-procedure actives — they support tissue repair and barrier recovery. Avoid retinol, exfoliating acids, and vitamin C immediately post-procedure. Always follow your provider's specific post-treatment protocol.

Do your products interact with prescription skincare?

If you are using prescription actives such as tretinoin, topical antibiotics, or immunomodulators, consult your dermatologist before adding new biotech actives. Some combinations may enhance or interfere with prescription efficacy.

Shipping & Delivery

Where do you ship?

We ship domestically within the United States and internationally to select countries. Shipping availability and rates are calculated at checkout based on your delivery address.

How long does shipping take?

Domestic orders typically arrive within 3–7 business days. International orders may take 7–21 business days depending on destination and customs processing. Expedited options may be available at checkout.

How do I track my order?

Once your order ships, you will receive a confirmation email with a tracking number. You can also view your order status by logging into your account.

Do you offer free shipping?

Free shipping thresholds and promotions are updated regularly. Check the banner at the top of our site or your cart for current offers.

Will I be charged customs or import duties?

International orders may be subject to customs duties, taxes, or import fees depending on your country. These charges are the responsibility of the recipient and are not included in our pricing or shipping fees.

My order hasn't arrived. What should I do?

First, check your tracking number for the latest status. If your package shows as delivered but you haven't received it, check with neighbors and your building's mail area. If the issue persists, contact us at support@serumscientist.com with your order number and we will investigate promptly.

Can I change my shipping address after placing an order?

We process orders quickly. Contact us immediately at support@serumscientist.com if you need to update your shipping address. We cannot guarantee changes once an order has entered fulfillment.

Returns & Refunds

What is your return policy?

We accept returns on unopened, unused products within 30 days of delivery. Due to the nature of skincare, opened products cannot be returned unless they are defective or damaged upon arrival. Visit our Refund Policy for full details.

My product arrived damaged. What do I do?

Please contact us within 7 days of delivery at support@serumscientist.com with your order number and a photo of the damage. We will arrange a replacement or refund promptly.

How do I initiate a return?

Email our support team at support@serumscientist.com with your order number and reason for return. Refunds are processed within 5–10 business days of receiving the returned item.

Can I exchange a product?

Yes, exchanges are available for unopened products within 30 days. Contact our support team to arrange an exchange for a different product of equal or lesser value.

How long does a refund take to appear?

Once we process your refund, it typically appears on your original payment method within 5–10 business days, depending on your bank or card issuer.

Orders & Account

Do I need an account to place an order?

No. You can check out as a guest. However, creating an account lets you track orders, save your address, and access your order history. Register here or sign in here.

Can I change or cancel my order after placing it?

We process orders quickly. If you need to make a change or cancellation, contact us immediately after placing your order at support@serumscientist.com. We cannot guarantee changes once an order has entered fulfillment.

I forgot my password. How do I reset it?

Click "Forgot password" on the login page and enter your email address. You will receive a reset link within a few minutes. Check your spam folder if it does not arrive.

How do I update my shipping address or contact details?

Log in to your account and navigate to your profile settings. Changes apply to future orders only.

Do you offer a loyalty or rewards program?

We are working on it. Sign up for our email list to be the first to know when our loyalty program launches.

Do you offer gift cards?

Check our store for current gift card availability. Gift cards are a great way to share the science with someone you care about.

Do you offer subscriptions or auto-replenishment?

We are actively developing subscription options for our most popular actives. Sign up for our email list to be notified when this launches.

The Science Journal

What is the Science Journal?

The Science Journal is SerumScientist.com's growing library of in-depth, research-backed articles covering the biology of skin aging, longevity actives, ingredient mechanisms, and emerging science in regenerative medicine. It is free, ungated, and written in plain language.

What series are in the Science Journal?

• Decoded Series — Deep dives into specific actives: how they work, what the research says, and how to use them correctly.
• Ask The Scientist — We take the most viral, most debated claims in health and skin and run them through the science lab. No hype. No marketing spin. Just the biology.
• Trending Now — Emerging ingredients and protocols gaining traction in clinical and consumer research, evaluated with scientific rigor.

Is the Science Journal free to read?

Yes — completely free, no account required. We believe an informed customer is an empowered one. The Science Journal is our commitment to that belief.

How often is the Science Journal updated?

We publish new articles regularly. Follow us or sign up for our email list to be notified when new content goes live.

Explore the Science Journal →

Still Have Questions?

We read every message. We respond to every question. That's not a policy — it's a practice.

The science of skin, finally within reach.
— The Serum Scientist Team

© 2026 SerumScientist.com. All rights reserved. This page is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before beginning any new skincare regimen.