COSRX
The Blue Peptide Bakuchiol Plump Glow Serum 50ml
A 50ml serum for the look of fine lines and slack texture, built as a gentler alternative for anyone who cannot tolerate a retinoid.
No reviews yet50 ml
$95.00 per 100 ml
- Korean-market formula
- Ships from California or direct from Korea
- Korean barcode and batch code intact
- Suited to
- Normal skinDry skinCombination skinSensitive skin
- Helps with
- The look of fine linesSlack looking textureA gentler alternative to a retinoid
In stock. Arrives in 3 to 7 business days
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How it works
This serum belongs to the group of formulas built for people who want work on the look of fine lines without the peeling and flushing that a retinoid brings for some skin. It is a leave-on serum used morning and night rather than a rationed few nights a week, which is the practical advantage: consistency instead of a schedule you have to manage. The finish is thin enough to sit under sunscreen, so it fits a morning routine as well as an evening one. That is the difference from a retinoid oil, which does more for some people but has to be built up slowly and kept to nights. What you can judge is whether fine texture reads softer in the same light after two months.
Key benefits
- Butylene Glycol sits near the top on this product's own ingredient list, a multifunctional glycol that carries moisture and helps preserve the formula.
- A brightening, sebum-regulating amide that also reinforces the skin barrier, and Niacinamide is right there in this product's ingredient list, near the top.
- On this formula's own list, Copper Tripeptide shows up near the top. It is a peptide, included to support skin's structural resilience.
Inside the formula
Inside the formula
What is this serum for?
The look of fine lines and slack texture, and it is usually bought by people who found a retinoid too much for their skin. It is a twice daily serum rather than a rationed one. You judge it on whether fine texture reads softer in the same light after two months.
Where does it go in my routine?
After the toner and before the cream, morning and night. It is thin enough to sit under sunscreen, which is what makes morning use practical. In the evening it goes on before your night cream, on damp skin, with nothing else strong in the same sitting.
Can I use it instead of a retinoid?
That is the usual reason people choose it. If a retinoid left your skin peeling or flushed, this is the gentler route to similar territory, and being usable twice daily helps. If you already tolerate a retinoid well, you do not need to swap, and using both means separating them across the week.
Can I use it with a retinoid?
Not in the same sitting. Put one on some evenings and the other on the rest, or keep this one for mornings and the retinoid for nights. Stacking two demanding steps together is how people end up flushed and then abandon both rather than finding out what worked.
Is this the Korean-market formula?
Yes. This is the Original Korean Formula 50ml bottle, the same one sold on Korean shelves.
Not on the ingredient list below: fragrance or parfum, essential oils, parabens, sulfate surfactants, mineral oil or petrolatum and added color.
Full INCI (39): Aqua/Water, Butylene Glycol, Glycerin, Dipropylene Glycol, Niacinamide, 1,2-Hexanediol, Betaine, Diethoxyethyl Succinate, Ammonium Acryloyldimethyltaurate/VP Copolymer, Dimethicone, Copper Tripeptide-1, Polyglyceryl-6 Caprylate, Polyglyceryl-4 Caprate, Bakuchiol, Hydrogenated Lecithin, Alcohol, Sodium Methyl Stearoyl Taurate, Ethylhexylglycerin, Hydroxypropyl Starch Phosphate, Disodium EDTA, Adenosine, Caprylyl Glycol, Tocopherol, Dipeptide Diaminobutyroyl Benzylamide Diacetate, Acetyl Hexapeptide-1, Acetyl Heptapeptide-4, Panthenol, Inositol, Acetyl Hexapeptide-8, Sodium Hydroxide, Propanediol, Beta-Glucan, Sodium Hyaluronate, Hyaluronic Acid, Sodium Hyaluronate Crosspolymer, Hydrolyzed Collagen, Hydrolyzed Hyaluronic Acid, Sodium Acetylated Hyaluronate, Acetyl Octapeptide-3
Ingredient list read from incidecoder.com on 10 September 2026.
39 of 39 explained
- Aqua/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.
- 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.
- 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.
- 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.
- 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.
- 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.
- Diethoxyethyl Succinate solvent
- Diethoxyethyl Succinate is a solvent that helps water-resistant actives spread and sink in evenly. It also leaves a light, silky feel.
- Ammonium Acryloyldimethyltaurate/VP Copolymer thickener
- This is a synthetic thickener that gels quickly and holds an emulsion stable across a wide pH range. It gives a light, non-tacky body.
- Dimethicone silicone
- Dimethicone is the most used cosmetic silicone. It forms a breathable film that smooths the surface, slows water leaving skin, and gives the slip that makes a primer or cream feel silky. It is inert and does not penetrate.
- Copper Tripeptide-1 peptide
- Copper Tripeptide-1 is three amino acids bound to a copper ion, and the classic firming peptide in cosmetic chemistry. It is blue in solution, which is often why a serum carrying it is tinted, and it is used for the look of firmness and fine lines.
- Polyglyceryl-6 Caprylate emulsifier
- A polyglycerin emulsifier with a short fatty chain, which makes it more water-loving than its longer-chain relatives. It suits cleansing waters and micellar formulas.
27 more explained
- Polyglyceryl-4 Caprate emulsifier
- Polyglyceryl-4 Caprate is a mild sugar-derived solubiliser used to dissolve fragrance and oil into watery formulas.
- Bakuchiol active
- 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.
- 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.
- Alcohol solvent
- Alcohol here means ethanol. It dissolves ingredients water cannot, evaporates fast so a formula sets quickly and does not feel heavy, and thins texture. In quantity it can leave dry or reactive skin feeling tight, which is why many Korean formulas avoid it and some deliberately use it for a fast, weightless finish.
- Sodium Methyl Stearoyl Taurate surfactant
- A taurine-based surfactant. Taurates foam well while staying mild, and they keep working in hard water where a soap does not.
- 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.
- Hydroxypropyl Starch Phosphate thickener
- Hydroxypropyl Starch Phosphate is a modified starch used to thicken and to take the sticky edge off a formula, leaving a powdery finish.
- 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.
- 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.
- Caprylyl Glycol preservative booster
- Caprylyl Glycol is a glycol that conditions skin and, more importantly, strengthens a preservative system so less of the traditional preservative is needed. It appears in most modern formulas built without parabens.
- 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.
- Dipeptide Diaminobutyroyl Benzylamide Diacetate peptide
- This is a two-amino-acid peptide, sold as Syn-Ake, used for the look of expression lines. Its structure was modelled on a component of snake venom, though nothing of the venom itself is in it.
- Acetyl Hexapeptide-1 peptide
- Acetyl Hexapeptide-1 is a six-amino-acid peptide used for the look of even tone. It is one of the few peptides aimed at pigment rather than at lines.
- Acetyl Heptapeptide-4 peptide
- A seven-amino-acid peptide with an acetyl group added for stability. It is used as a conditioning peptide for the look of firmness.
- Panthenol humectant
- Panthenol is pro-vitamin B5: skin converts it to pantothenic acid. It is a humectant that holds water and leaves skin feeling soft and less tight, and it is one of the ingredients formulators reach for when a formula also contains something harsh.
- 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.
- Acetyl Hexapeptide-8 peptide
- Acetyl Hexapeptide-8 is a six-amino-acid peptide used for the look of expression lines, particularly around the eyes. It is the peptide sold under the name Argireline and is water soluble and stable.
- Sodium Hydroxide pH adjuster
- Sodium Hydroxide is a strong base used in traces to bring an acidic formula up to skin-friendly pH. None of it remains as itself once the formula is neutralised.
- 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.
- 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.
- 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.
- 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.
- Sodium Hyaluronate Crosspolymer humectant
- Sodium Hyaluronate Crosspolymer is hyaluronic acid linked into a mesh. It holds water in a soft gel on the surface rather than sinking in, and it releases that water slowly through the day.
- Hydrolyzed Collagen protein
- Hydrolyzed Collagen is collagen broken into fragments small enough to dissolve in water. It cannot become collagen in skin; what it does is hold water at the surface and leave a smooth, conditioned film.
- 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 Acetylated Hyaluronate humectant
- Sodium Acetylated Hyaluronate is hyaluronic acid modified to be part oil-loving, so it clings to skin instead of rinsing away. Formulators call it the one that stays put.
- Acetyl Octapeptide-3 peptide
- Acetyl Octapeptide-3 is an eight-amino-acid peptide used for the look of expression lines. It is usually paired with acetyl hexapeptide-8 rather than used alone.
- Market
- Korean market, the version sold in Korea
- EAN (barcode)
- 8809598455191
- Made in
- Republic of Korea
- Volume
- 50 ml
- Category
- Serum & Ampoule
- Actives
- Adenosine, Bakuchiol, Beta-Glucan, Collagen, Hyaluronic Acid, Niacinamide, Panthenol, Peptides, Sodium Hyaluronate
- 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.
How to use
- Apply after the toner while the skin is still damp so it spreads across the face in one pass.
- Press it in and work upward along the jaw and cheek rather than dragging downward.
- Follow with a cream to hold it in place, and with sunscreen as the final morning step.
- Do not use it in the same sitting as a retinoid product, and give each of them their own part of the week instead.
Worth knowing
- Patch test along the jaw for two days first, since this is a twice daily leave-on serum.
- Give it two months before judging it, because a change in fine texture cannot be read in a fortnight.
Complete the routine
- This itemCOSRX The Blue Peptide Bakuchiol Plump Glow Serum 50ml$47.50
- Seal the routine in as the last stepCOSRX Skin Barrier Moisturizing Cream 450ml$42.50
- An as-needed step, in place of the prep layerCosrx 5 PDRN Hyaluronic Acid Vital Hydrating Hydrogel Mask$4.70
Total for 3 items$94.70
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COSRX The Blue Peptide Bakuchiol Plump Glow Serum 50ml
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COSRX, Korean-market original
A 50ml serum for the look of fine lines, stocked in the Original Korean Formula.
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.
COSRX verifies units itself. Find the verification page on cosrx.com and enter the batch number and expiration date printed on your unit. Read them off the package rather than from us, which is the point.
Source: COSRX FAQ
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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