Where does this serum go in my routine?

After toner and before moisturizer, morning and evening. Anything thinner than a serum goes on before it, and anything richer goes on after. If you are adding it to a routine you already like, give it a week on its own first, so what you see is the Niacinamide and not three changes at once.

Is this the Korean-market serum or a US version?

The Korean-market one, Niacinamide and all. We match this serum to its Korean barcode before it reaches the shelf, which is the check that tells you which market release you are holding.

Does this serum contain fragrance?

Yes. The ingredient list names Fragrance. It sits on the panel printed on this page, so you can read the position for yourself before you buy. If fragrance components are something you avoid, this serum is not the one.

What else is on the list besides Niacinamide?

Adenosine, Capryloyl Salicylic Acid and Zea Mays (Corn) Kernel Extract. The order they are printed in on this serum's panel is the order on the box, so you can see where Niacinamide sits relative to them. Further down the same panel: Cetyl Ethylhexanoate, Glycereth-25 PCA Isostearate and Arginine.

Cell Fusion C

Glass Skin Serum 30ml

Name: Cell Fusion C Glass Skin Serum 30ml
Brand: Cell Fusion C
SKU: 11017381578
Price: 37.5 USD
Availability: InStock

Glass Skin Serum is Cell Fusion C's toner (30ml), built around Niacinamide and Adenosine. It is used right after cleansing, to rebalance the skin and prep it for the next step. This is the same formula Korean shoppers buy off the shelf in Seoul, not a version built for US retail.

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$37.50

30 ml

$125.00 per 100 ml

Korean-market formula
Ships from California or direct from Korea
Korean barcode and batch code intact

Suited to: Congested skinUneven textureDehydrated skinSensitive skin

Helps with: Shoppers looking for Niacinamide in a serumRoutines that want Niacinamide and Adenosine in one stepFilling the serum step with a Korean-market formulaAnyone who wants the Niacinamide serum sold on Korean shelves

One-time purchase

$37.50

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$33.75

In stock. Arrives in 3 to 7 business days

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How it works

The Glass Skin Serum is a 30ml serum, used after toner and before moisturizer, morning and evening. The active it is built around is Niacinamide, named sixth on its own ingredient list. The same list carries Adenosine, Capryloyl Salicylic Acid and Zea Mays (Corn) Kernel Extract, so the active is not the only thing on it worth naming. How much of the Niacinamide stays on the skin, and for how long, is decided by the serum format rather than by the list alone. This is the Original Korean Formula, the serum Cell Fusion C sells in Korea, Niacinamide and all.

Key benefits

Niacinamide, the active this serum is built around
Adenosine on the same list, an active
Capryloyl Salicylic Acid on the same list, an exfoliant
Zea Mays (Corn) Kernel Extract on the same list, a plant extract
Glycereth-25 PCA Isostearate and Arginine further down the same list
Methyl Gluceth-20 and Hyaluronic Acid further down the same list

Inside the formula

Ingredients declared

#24

Fragrance on the list

1 of 3

35 of 36 explained

Water solvent: Water is the base almost every serum, toner and cream is built on. It dissolves the water-loving ingredients and sets how light the finished texture feels. On an INCI list it is usually first, which only means it is the largest single ingredient by weight.
Glycerin humectant: Glycerin is the most used humectant in skincare. It draws water into the outer layer of skin and holds it there, and it is one of the very few ingredients whose hydrating effect is settled science rather than marketing. Higher amounts feel tacky, which is why it is usually blended.
Butylene Glycol humectant: Butylene Glycol is a small glycol that does two jobs at once: it holds water in the top layer of skin and it dissolves plant extracts and actives that plain water cannot. It also thins a formula, which is why watery Korean essences lean on it.
Dipropylene Glycol humectant: Dipropylene Glycol is a glycol used as a solvent and a light humectant. Its main job is keeping the rest of the formula dissolved and the texture fluid rather than adding hydration of its own.
Propanediol humectant: Propanediol is a plant-derived glycol used in place of propylene glycol. It hydrates, carries actives into solution, and gives a lighter, less sticky slip than glycerin at the same strength.
Niacinamide active: Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. It is used at roughly 2 to 5 percent for the look of uneven tone and visible pores, and it is water soluble, stable and comfortable beside almost every other active, which is why it turns up in so many lists.
Alcohol Denat solvent: Alcohol Denat. is ethanol with a bitter additive that makes it undrinkable, which is a tax rule rather than a formulation choice. It behaves like alcohol: a fast-evaporating solvent that gives a weightless finish and can feel drying at higher levels.
Methyl Gluceth-20 humectant: Methyl Gluceth-20 is a sugar-derived humectant. It holds water in the outer layer of skin and gives a smooth, cushioned slip that plain glycerin does not.
1,2-Hexanediol humectant: 1,2-Hexanediol is a glycol used for two reasons: it holds water like glycerin, and it makes a formula harder for microbes to live in, so less traditional preservative is needed. Korean formulas use it heavily for that second reason.
Arginine amino acid: Arginine is an amino acid that does two jobs here: it holds water in the outer layer of skin, and it neutralises acidic gelling agents, which is why it often stands in for a synthetic pH adjuster.
Ethylhexyl Palmitate emollient: Ethylhexyl Palmitate is a palm-derived ester used as a light emollient and a solvent for pigment. It gives a smooth, non-greasy slip.
Acrylates/C10-30 Alkyl Acrylate Crosspolymer thickener: This is a carbomer relative with fatty side chains, so it thickens and stabilises an emulsion at the same time. It gives a light gel-cream body rather than a heavy one.

23 more explained

Hydroxyacetophenone preservative booster: Hydroxyacetophenone is an antioxidant that also strengthens a preservative system, so a formula needs less traditional preservative. Korean formulas pair it with 1,2-hexanediol constantly.
Carbomer thickener: Carbomer is a synthetic polymer that only gels once a base neutralises it, which is why arginine or tromethamine sits nearby on the list. It gives the clear, non-stringy gel texture a xanthan formula cannot reach.
Cetyl Ethylhexanoate emollient: Cetyl Ethylhexanoate is a synthetic ester used as a dry-feeling emollient. It spreads easily, leaves a silky rather than oily finish, and helps disperse pigments and UV filters evenly.
Sodium Polyacryloyldimethyl Taurate thickener: Sodium Polyacryloyldimethyl Taurate is a polymer thickener that holds a gel stable even with a lot of salt or acid in the formula.
Glycereth-25 Pca Isostearate emollient: Glycereth-25 PCA Isostearate is a water-dispersible emollient that softens skin and helps oils and water stay mixed. It reads as light rather than rich on the skin.
Betaine humectant: Betaine is a sugar-beet-derived humectant that cells use to hold water. In a formula it hydrates and takes the edge off cleansers and acids, which is why it often appears alongside them.
Polyglyceryl-10 Oleate emulsifier: Polyglyceryl-10 Oleate is a mild sugar-derived emulsifier and solubiliser used where a formula must stay clear.
Disodium EDTA chelator: EDTA is a chelator: it locks up trace metal ions from water and packaging that would otherwise turn a formula cloudy, off-colour or rancid. It does nothing to skin and appears at a fraction of a percent.
Ethylhexylglycerin preservative booster: Ethylhexylglycerin softens skin and boosts a preservative system, which is why it is nearly always sitting beside phenoxyethanol or 1,2-hexanediol. It also cuts down the odour bacteria produce, so it turns up in deodorising products.
Zea Mays (Corn) Kernel Extract plant extract: Corn kernel extract, mostly starch-derived sugars with some amino acids. It is used as a conditioning, water-holding extract.
Adenosine active: Adenosine is a nucleoside that Korea's own cosmetic authority recognises as a wrinkle-care functional ingredient, which is why it appears on so many Korean lists at a low level. It is used for the look of fine lines and is stable and well tolerated.
Fragrance fragrance: Fragrance, or Parfum, is a single declaration standing for a whole scent blend, which can be dozens of materials. Regulators allow it as a trade secret, so a list showing only this word does not say what the scent is made of. It is the most common trigger named by people with reactive skin.
Mica (Ci 77019) colorant: Mica is a mineral ground into fine flakes. It scatters light, so it lightens a shade and gives the soft glow of a tinted or illuminating product.
Hydrogenated Lecithin emulsifier: Hydrogenated Lecithin is lecithin with its unsaturated bonds filled in, which makes it far more stable. It emulsifies and is the standard shell for the liposomes that carry actives into the outer layer of skin.
Glyceryl Acrylate/Acrylic Acid Copolymer film former: This is a polymer that forms a moisture-holding film on the surface, usually supplied with glycerin and propylene glycol as a hydrating complex.
Hyaluronic Acid humectant: Hyaluronic Acid is a sugar chain the body already makes, and one gram of it can hold several litres of water. In a formula it is a humectant that pulls water to the surface of skin and holds it in a film, which is what makes skin look plumper while it is there.
Hydrolyzed Hyaluronic Acid humectant: Hydrolyzed Hyaluronic Acid is hyaluronic acid cut into much shorter fragments. The smaller the fragment, the further into the outer layer it can settle, which is why serums stack several sizes together instead of using one.
Sodium Hyaluronate humectant: Sodium Hyaluronate is the salt of hyaluronic acid, and it is what most products labelled hyaluronic actually contain. The salt dissolves more readily and the molecule is smaller, so it sits in the outer layer of skin rather than only on top of it.
Fructan humectant: Fructan is a chain of fructose units, usually from chicory. It holds water at the surface and forms a light, conditioning film.
Glucose humectant: Glucose is a simple sugar used as a humectant and as food for the ferment ingredients in the same formula. It hydrates mildly and adds a soft slip.
Capryloyl Salicylic Acid exfoliant: Capryloyl Salicylic Acid is salicylic acid with a fatty tail, sometimes sold as LHA. It stays nearer the surface than salicylic acid and works at a higher pH, so it exfoliates more evenly and more gently.
Hydroxypropyltrimonium Hyaluronate humectant: Hydroxypropyltrimonium Hyaluronate carries a positive charge, and skin carries a slight negative one, so it is attracted to the surface and stays through rinsing. It is the hyaluronic used where a formula gets washed off.
Inositol humectant: Inositol is a sugar-like compound found in the body. In skincare it is a humectant that also helps a formula feel conditioning rather than merely wet.

How to use

Sweep across a cleansed face and neck with a cotton pad or press in with clean hands, then continue with the rest of the routine without rinsing.

Worth knowing

Patch test this serum on a small area and wait a day before using it more widely, especially with Niacinamide on the list.
This list names Fragrance, so skip it if fragrance components are something you avoid.
Salicylic Acid on this list makes this serum an exfoliating step, so do not stack it with another one on the same night.

Complete the routine

This itemCell Fusion C Glass Skin Serum 30ml$37.50
The last step of the morning, over everything elseCell Fusion C Laser Sunscreen SPF50+/ PA++++ 50ml$30.00
The treatment step of this routineCell Fusion C Laser Rejuvenation Ampoule 30ml$27.50

Total for 3 items$95.00

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Cell Fusion C Glass Skin Serum 30ml

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Cell Fusion C, Korean-market original