K-Secret Seoul 1988 Serum
K-Secret Seoul 1988 Serum is a 30ml serum with Niacinamide, used after toner and before moisturizer, morning and evening.
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- Suited to
- Dry skinCompromised barrierDehydrated 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 formula
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- 30-day returns
- Free US shipping on orders of $100 or more
- Dispatched within 2 business days
How it works
The Seoul 1988 Serum is a 30ml serum, used after toner and before moisturizer, morning and evening. The active it is built around is Niacinamide, named seventh on its own ingredient list. The same list carries Adenosine, Retinal and Bakuchiol, 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. K-Secret sells this Niacinamide serum in Korea, and this is that version.
Key benefits
- Niacinamide, the active this serum is built around
- Adenosine, Retinal and Bakuchiol on the same list, actives
- sh-Oligopeptide-1 on the same list, a peptide
- sh-Oligopeptide-2 and Tocopherol further down the same list
- Pentaerythrityl Tetra-di-t-butyl Hydroxyhydrocinnamate and 3-O-Ethyl Ascorbic Acid further down the same list
- Niacinamide named seventh on the manufacturer list printed on this page
Key actives
Niacinamideactive
Niacinamide is vitamin B3, and it is the most studied active in Korean formulation. On this serum's own ingredient list it is named seventh.
Adenosineactive
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. The panel names it twenty-first on this serum's list, beside Niacinamide.
Retinalactive
Retinal is retinaldehyde, a vitamin A derivative one chemical step closer to retinoic acid than retinol is. It is yellow-orange and unstable in light, so products carrying it are usually opaque. The panel names it twenty-seventh on this serum's list, beside Niacinamide.
Bakuchiolactive
Bakuchiol is a compound from the babchi seed, used as a plant-derived alternative to retinol. It is oil soluble, stable in daylight and does not carry retinol's acclimatisation period, which is why sensitive-skin formulas choose it. It is named thirty-eighth on this serum's list, alongside Niacinamide.
sh-Oligopeptide-1peptide
sh-Oligopeptide-1 is a peptide made by yeast fermentation rather than synthesis, which is what the sh prefix records. It is used for the look of firmness and skin recovery after irritation. The panel names it thirty-ninth on this serum's list, beside Niacinamide.
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.
What else is on the list besides Niacinamide?
Adenosine, Retinal and Bakuchiol. 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: sh-Oligopeptide-1, sh-Oligopeptide-2 and Tocopherol.
- Ships from
- California
Duties are prepaid. Nothing is owed at delivery. Returns are accepted for 30 days, by mail.
Orders ship from our California warehouse, dispatched within 2 business days, and arrive in 3 to 5 days. Shipping is free on orders of $100 or more.
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 - 2Customs
Duty paid by us before it enters the US - 3California
Ships domestically, no international leg
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.
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.
Import duties are paid by us before the parcel reaches you, so nothing is owed at the door, 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.
Payment and security
We accept
How to use
- After toner, AM and/or PM. Press or smooth over the face and let it settle before the next step.
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.
- Retinal is on this list, so keep this serum to the evening and build the nights up slowly rather than starting nightly.
Reviews
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Korean-market original
The Original Korean Formula serum from K-Secret, 30ml formulated with Niacinamide and Adenosine, held in the United States and shipped domestically.
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.
Match the batch code on the box against the code printed on the bottle or tube itself; the two are stamped separately and should agree.
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 the key actives in this formula, quoted from the medical sources linked beside each.
Vitamin A has a molecular structure that's tiny enough to get into the lower layers of your skin, where it finds and boosts collagen and elastin, which is a protein that strengthens your skin's flexibility.
Wilma Bergfeld, MDDermatologist, Cleveland Clinic Bakuchiol is often used as a gentler alternative to retinol. It may help your skin look smoother and reduce the appearance of wrinkles.
Shilpi Khetarpal, MDDermatologist, Cleveland Clinic
1 more professional perspective
Niacinamide helps reduce the appearance of pores in a few ways. By strengthening the skin barrier and improving elasticity, pores appear less noticeable and more even.
Ashlyn YankeAesthetician, Cleveland Clinic
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