Wait, What's a Bond? And What Does Molecular Mean?

K18 has always been a biology-first brand. Our products make your results simple, but the biotech powering them is anything but.

For those without an advanced science degree, you might find yourself wondering what we mean when we say things like “biotech-powered” or what exactly K18’s biomimetic peptide does to your hair in simple terms. If you’ve ever perused our website and found yourself looking up terms you half-remember from high school biology, this story is for you.

At K18, we believe understanding the science matters. When you know how our patented technology works—and how your biology works—you’re better equipped to care for your hair and get the best results.

We invited the scientists behind K18’s innovations to answer some of your most frequently asked science questions. Let’s walk through the K18 lab and break down all this biotech into bite-sized bits, together.

what’s a bond?

In short, hair has three different types of bonds that help hold your hair together.

Covalent bonds (disulfide and peptide bonds)
These are strong and stable bonds. They give hair its structure, shape and strength—and they’re the ones broken by bleach, color, relaxers, and perms.
Ionic interactions (salt bridges)
Medium-strength bonds that help hair stay balanced. They’re affected by changes in pH (like chemical services).
Hydrogen bonds
The weakest and most temporary bonds. Water and heat break and reform them daily (this is what is happening when you style or shower)

When covalent (disulfide) bonds break (through harsh processes like bleaching or coloring), you need more than surface-level repair to bring back hair’s integrity.

what about polypeptide chains?

Polypeptide chains are long strands of amino acids linked by peptide bonds. These chains are the building blocks of keratin—your hair’s main protein.

Keratin is what gives your hair strength, structure and elasticity.

When hair is damaged, these polypeptide chains break apart. K18PEPTIDE™ is specifically designed to reconnect broken polypeptide chains at every layer of the structure rather than coating hair in order to help restore hair’s strength and elasticity from the inside out.

what does “biomimetic” even mean?

Biomimetic means “designed to mimic nature.” All of our core technologies at K18 are inspired by nature’s intelligent design and processes; solutions the natural world has spent millions of years honing to perfection.

K18PEPTIDE™ is a biomimetic technology that mimics the peptides naturally found in healthy hair. It works with our biology, binding to sites in your hair’s polypeptide chains.

how does biotech work in haircare?

Biotechnology (aka biotech) uses biology as its inspiration—then recreates these natural processes safely in the lab to be more effective, sustainable, and intentional. This biology-first approach allows for precise, targeted solutions that traditional cosmetic ingredients can’t achieve, moving us from the age of cosmetic chemistry and superficial results, to molecular repair and new breakthrough technology to deliver long-lasting results.

It took more than 10 years of study in hair biology to design, develop, test and patent K18PEPTIDE™, the greatest discovery in hair history. It’s biomimetic to hair's keratin (a natural protein), clicking into its structure to reconnect broken disulfide bonds and polypeptide chains, reversing damage where it matters most and where all hair is the same: the molecular level.

Its discovery marks the first long-lasting solution to hair damage—effectively defining an entirely new category of haircare. You can find it in our leave-in molecular repair mask + molecular repair oil.

But K18 didn’t stop innovating at repair. Our research continues to push the envelope of what is possible for haircare.

AirWash™: odorBIND™ smart-release technology harnesses the understanding of nature and biology to uniquely recognize, trap, and eliminate malodors, rendering them undetectable and releasing a subtle fragrance in their place.
HeatBounce: resilicore™ heat-shielding technology is inspired by proteins in nature that can withstand extreme stresses, and provides a protective shield that fortifies hair from within for maximum protection against breakage, dry feeling, dullness and color fade.

why does K18 formulate with biotech?

Biotech is…

effective – can be designed to target specific molecular interactions
consistent – lab-created ingredients are pure and controlled
sustainable – minimizes reliance on limited natural resources

why is a peptide better than a protein for repair?

In short—size matters, a lot.

Proteins are large → they can sit on the outside of hair and can cause buildup.
Peptides are small → they can penetrate into hair’s innermost layers, where damage lives.

However, both serve a purpose for your hair’s biology. Proteins have complex compositions + perform many functions. Peptides can also be selected or designed (like K18PEPTIDE™ was) to have very specific charge and composition to have very specific function and interactions with damaged hair.

what does molecular mean (and why does it matter for hair repair)?

The word molecular means relating to, consisting of, or produced by molecules, which are the tiny particles (groups of two or more atoms) that make up chemical substances, organisms, and everything else in the universe. When we say the K18 mask repairs on a molecular level, we mean it works within the deepest, innermost layers of your hair where strength and elasticity start and only a peptide can reach.

Now that we’ve broken down the science behind K18 in small, easy-to-understand bits, things might start to click in a new, lets-all-put-on-our-lab-coats, kind of way.

If you enjoyed this breakdown and want to learn even more about the ever-evolving world of biotech, we’ve got so much more for you on the blog.

*k18hair.com/disclaimers