Cell Fusion C
Toning C Dark Spot Serum 30ml
Toning C Dark Spot Serum is Cell Fusion C's ampoule serum (30ml), built around Niacinamide and 3-O-Ethyl Ascorbic Acid. It is used after toner and before moisturizer, as the routine's concentrated treatment step. This is the Original Korean Formula, not a version reworked for US retail.
No reviews yet30 ml
$141.67 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 Allantoin in one stepFilling the serum step with a Korean-market formulaAnyone who wants the Niacinamide serum sold on Korean shelves
In stock. Arrives in 3 to 7 business days
We accept
You’re $100.00 away from free US shipping.
- 30-day returns
- Free US shipping on orders of $100 or more
- Tracked delivery to your door
How it works
The Toning C Dark Spot Serum is a 30ml serum, used after toner and before moisturizer, morning and evening. The active it is built around is Niacinamide, named third on its own ingredient list. The same list carries Allantoin, Adenosine and Sphingomonas Ferment 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
- Allantoin and Adenosine on the same list, actives
- Sphingomonas Ferment Extract on the same list, a ferment
- 3-O-Ethyl Ascorbic Acid on the same list, an antioxidant
- Tocopherol and Ferulic Acid further down the same list
- Fullerenes and Ascorbic Acid further down the same list
How to use
- Apply after toner and before moisturizer. Pat or smooth it over a cleansed face and let it absorb before the next step, AM and PM.
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 Geraniol and Limonene. They sit 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?
Allantoin, Adenosine and Sphingomonas Ferment 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: 3-O-Ethyl Ascorbic Acid, Tocopherol and Ferulic Acid.
Not on the ingredient list below: fragrance or parfum, denatured or SD alcohol, silicones, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (31): Water, Propanediol, Niacinamide, 1,2-Hexanediol, 3-O-Ethyl Ascorbic Acid, Sphingomonas Ferment Extract, Melissa Officinalis Leaf Extract, Citrus Aurantium Dulcis (Orange) Peel Oil, Hydrogenated Lecithin, Cymbopogon Martini Oil, Rosa Damascena Flower Oil, Octyldodeceth-16, Allantoin, Glycerin, Polyacrylate Crosspolymer-6, Tocopherol, Polyglyceryl-10 Laurate, Ferulic Acid, Beta-Glucan, Disodium EDTA, Butylene Glycol, Adenosine, Citric Acid, Rosmarinic Acid, Polyglyceryl-3 Methylglucose Distearate, Fullerenes, Ascorbic Acid, Caprylic/Capric Triglyceride, Ethylhexylglycerin, Limonene, Geraniol
Ingredient list read from inkeedecoder.com on 10 September 2026.
30 of 31 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.
- 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.
- 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.
- 3-O-Ethyl Ascorbic Acid antioxidant
- 3-O-Ethyl Ascorbic Acid is a stable vitamin C derivative that skin converts to ascorbic acid. It survives in a formula far better than pure vitamin C and works at a gentler pH, so it suits skin that finds the pure acid uncomfortable.
- Sphingomonas Ferment Extract ferment
- Sphingomonas Ferment Extract is the liquid left after Sphingomonas bacteria have fermented a sugar substrate. It carries water-holding polysaccharides and is used as a conditioning ferment.
- Melissa Officinalis Leaf Extract plant extract
- Lemon balm extract, a mint-family herb rich in rosmarinic acid. It is used as an antioxidant conditioning extract with a light lemon scent.
- Citrus Aurantium Dulcis (Orange) Peel Oil fragrance component
- Sweet Orange Peel Oil is a citrus essential oil carrying limonene. It scents a formula, and limonene is one of the components EU labelling names separately.
- 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.
- Cymbopogon Martini Oil fragrance component
- Palmarosa oil, distilled from a grass related to lemongrass. It is high in geraniol and carries a rose like scent, so it is used as an aromatic oil.
- Rosa Damascena Flower Oil fragrance component
- Rosa Damascena Flower Oil is rose essential oil, one of the most expensive materials in perfumery. It scents a formula, and like every essential oil it is a class reactive skin often does not tolerate.
- Octyldodeceth-16 emulsifier
- An ethoxylated branched fatty alcohol. It emulsifies and also gives a formula a soft, cushioned slip.
18 more explained
- Allantoin active
- Allantoin is a comfrey-derived compound used to condition skin and soften the outer layer so it feels smoother. It is one of the standard additions to a formula built for easily irritated skin.
- 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.
- Polyacrylate Crosspolymer-6 thickener
- Polyacrylate Crosspolymer-6 is a thickener chosen for a notably fresh, bouncy gel feel that breaks down to water on the skin.
- Tocopherol antioxidant
- Tocopherol is vitamin E. It is an oil-soluble antioxidant that protects the oils in a formula from going rancid and works on skin as an emollient, and it is regularly paired with vitamin C because each keeps the other going for longer.
- Polyglyceryl-10 Laurate emulsifier
- Polyglyceryl-10 Laurate is a sugar-derived emulsifier and solubiliser, mild enough to be a standard choice in Korean essences. It dissolves small amounts of oil into water without any tightening feel.
- Ferulic Acid antioxidant
- Ferulic Acid is a plant antioxidant from bran and seeds. Its main formulation job is stabilising vitamins C and E so a serum keeps working for longer, which is why the three appear together so often.
- Beta-Glucan polysaccharide
- Beta-Glucan is a polysaccharide from oats or yeast. It holds a large amount of water, forms a soothing film, and is one of the ingredients formulators reach for in products aimed at reactive skin.
- 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.
- 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.
- 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.
- Citric Acid pH adjuster
- Citric Acid is used in tiny amounts to bring a formula to the pH its actives need, not as an exfoliant at that level. It is an AHA, so at much higher concentrations it can also exfoliate.
- Polyglyceryl-3 Methylglucose Distearate emulsifier
- Polyglyceryl-3 Methylglucose Distearate is a sugar-derived emulsifier known for a light, non-soapy feel. It builds gel-creams that do not read as rich.
- Fullerenes antioxidant
- Fullerenes are hollow cage-shaped carbon molecules, C60 the best known of them. They are used as an antioxidant and are notably more stable than the vitamin antioxidants.
- Ascorbic Acid antioxidant
- Ascorbic Acid is pure vitamin C, the most researched form and also the least stable: it needs a low pH and airtight packaging to stay active. It is an antioxidant used for the look of dullness and uneven tone.
- Caprylic/Capric Triglyceride emollient
- Caprylic/Capric Triglyceride is the light fraction of coconut oil, with the heavy parts removed. It is the workhorse emollient of modern formulas: it softens skin, dissolves oil-soluble actives and absorbs without the greasy weight of a whole plant oil.
- 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.
- Limonene fragrance component
- Limonene is the citrus-peel aromatic. It appears here because EU labelling requires 26 fragrance components to be named individually rather than hidden inside "fragrance", and it is one of them.
- Geraniol fragrance component
- Geraniol is a rose-scented aromatic found in geranium and citronella oils. It is one of the 26 declarable fragrance components.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809694624101
- Made in
- Republic of Korea
- Volume
- 30 ml
- Category
- Serum & Ampoule
- Actives
- Adenosine, Allantoin, Beta-Glucan, Niacinamide, Vitamin C
- Ships from
- California or Korea
Orders ship from California or direct from Korea with tracked delivery to your door, and both routes carry the same Korean-market release. Shipping is free on orders of $100 or more. Returns are accepted for 30 days, by mail.
We split shipments free, so one out-of-stock item never holds up the rest of your order.
Where this unit came from
- 1Seoul
Bought as Korean-market stock - 2Barcode
Listed against the Korean barcode on its box - 3California or Korea
Ships to you from either, as the same Korean-market release
We stock the version of a formula that is sold in Korea, not the release a brand prepares for another market under the same name. The barcode in the specification above is the Korean-market one and it is printed on the box you receive.
Every unit keeps its original barcode and batch code intact, so the unit in your hands can be checked against the brand’s own records.
Every order ships from California or direct from Korea, and returns run for 30 days.
Every claim on this page traces to the unit in the box, the barcode, the batch code and the price you can read for yourself.
Inside the formula
Inside the formula
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 Geraniol and Limonene, so skip it if fragrance components are something you avoid.
Complete the routine
- This itemCell Fusion C Toning C Dark Spot Serum 30ml$42.50
- 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$100.00
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Cell Fusion C Toning C Dark Spot Serum 30ml
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Cell Fusion C, Korean-market original
Toning C Dark Spot Serum, 30ml, Cell Fusion C's ampoule serum with Niacinamide and 3-O-Ethyl Ascorbic Acid.
Verify your unit when it arrives
Verify your unit when it arrives
Korean-market stock with the original barcode and batch code intact, exactly as it left Korea.
On the unit itself
- The Korean-market barcode, unaltered from the retail package.
- The manufacturer’s batch code, exactly as the maker printed it.
정품Genuine article, Korean-market stock
What professionals say
What professionals say
What skin-care professionals say about skin care, quoted from the medical sources linked beside each.
Your skin barrier is basically your outer layer of the skin.
Melissa Piliang, MDDermatologist, Cleveland Clinic Pretty much every step of a Korean skin care routine is going to have some component of hydration.
Alok Vij, MDDermatologist, Cleveland Clinic
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