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The Science

Peptides, Explained

A closer look at the actives inside the SIIS Copper Peptide GHK-Cu Collagen Support / Elasticity Serum — described in plain, honest cosmetic language.

The Foundation

What Are Peptides?

Peptides are short chains of amino acids — the building blocks of proteins.

In skincare, specific peptides are chosen for how they help skin look and feel: smoother, more supple, firmer-looking. Some are bound to minerals such as copper; others are paired with a fatty acid (a “palmitoyl” group) to help them work in harmony with the skin’s surface.

SIIS was founded around this category. Our first formula pairs two of its most celebrated technologies.

Abstract gold peptide molecule with a copper-blue center
The Actives

Inside the Bottle

GHK-Cu

Copper Tripeptide-1

A small peptide of three amino acids (glycine, histidine and lysine) bound to copper. First described by researchers in the 1970s, GHK-Cu has become one of the most sought-after ingredients in modern skincare, used to help improve the look of firmness, elasticity and tone. It is also what gives the serum its natural blue tint.

PAL-150

Palmitoyl Tripeptide-1 + Palmitoyl Tetrapeptide-7

A well-known pairing of two signal peptides, widely used in modern formulations to help improve the look of smoother, firmer skin and fine lines. Working alongside GHK-Cu, the complex completes the serum’s peptide profile.

HA

Hyaluronic Acid

Sodium hyaluronate provides lightweight hydration for a supple, plump appearance, and helps create the serum’s silky, fast-absorbing feel.

BOTANICALS

Organic Oils & Extracts

Organic jojoba seed oil, organic coconut oil, organic green tea leaf extract and orange peel extract round out the formula with a comforting, nourishing finish.

Copper-blue serum texture
Good to Know

Using Copper Peptides Well

Consistency

Peptides are a daily ritual. Apply morning and night to clean face and neck.

Layering

Many people prefer not to apply copper peptides in the same step as strong exfoliating acids or pure vitamin C. Alternate them morning and night instead.

Protection

Finish your morning ritual with a broad-spectrum sunscreen.

Patch Test

As with any new skincare, test on a small area first.

Transparency

Full Ingredient List

Purified Water, Glycerin, Hyaluronic Acid (Sodium Hyaluronate), Copper Tripeptide-1, Palmitoyl Tripeptide-1, Palmitoyl Tetrapeptide-7, Citrus Aurantium Dulcis (Orange) Peel Extract, Organic Cocos Nucifera (Coconut) Oil, Organic Simmondsia Chinensis (Jojoba) Seed Oil, Organic Camellia Sinensis (Green Tea) Leaf Extract, Butylene Glycol, Carbomer, Polysorbate 20, Phenoxyethanol.

These statements have not been evaluated by the Food and Drug Administration. This cosmetic product is not intended to diagnose, treat, cure, or prevent any disease. For external use only. Discontinue use if irritation occurs.

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