"Salmon DNA Serums: I Checked the Science on 4 Viral Products"

6 September 2026

Salmon DNA — PDRN — is the skincare ingredient of the year. We read the labels on four of the most talked-about PDRN serums and checked what the studies actually tested. One brand prints the exact amount of salmon DNA in its formula: 100 parts per million, next to 29,049 ppm of hyaluronic acid in the same bottle. The short answer: the biology is real, the injected version has the evidence, and nobody has yet shown that the serum gets where it needs to go.

What we checked

Prices move; check before you buy. Nothing here was sponsored.

What the label said

Medicube. Sold as 10,000 ppm of salmon DNA — but that figure sits on retailers' pages, not the brand's own [9]. The ingredient list also differs between countries, and every version we read contains fragrance.

Anua. The one brand that prints its numbers. Beside each ingredient is a concentration: hydrolysed hyaluronic acid at 29,049 ppm, salmon DNA at 100 ppm [9]. The brand's own claims are footnoted too. Skin "8.93% plumper" was measured three seconds after application, in a test of 23 women aged 40 to 68. "Collagen up 67.6%" was measured in fibroblasts — cells in a dish, not faces. None of that is hidden, and Anua deserves credit for publishing it.

Numbuzin. Fragrance-free and the cheapest of the four. The front of the bottle says 5% Rose PDRN. The ingredient list says sodium DNA at 0.05%. The 5% describes a blend; the DNA itself is a hundredth of it [9].

Rejuran. Rejuran is not a beauty brand borrowing a science word. It is the company behind the injectable polynucleotide — the only commercial one permitted to be injected directly into skin in Korea [4].

Put side by side, the disclosed DNA levels run from 100 ppm (Anua) to 500 (Numbuzin), 5,000 (Rejuran) and 10,000 (Medicube, per retailers). That is a hundredfold spread on one ingredient in one aisle.

What the evidence shows

Where it came from. PDRN was approved in Italy in 1994 as a drug for wounds and skin ulcers [3]. It works through a receptor deep in the skin, in the dermis. Since March 2026 it has been on the shelves of about 380 Sephora stores, according to the company's launch announcement [8].

The number nobody prints. Skin is a barrier. The working rule is that molecules bigger than about 500 daltons do not passively cross it. These DNA fragments are measured in the tens to hundreds of thousands of daltons [1][7]. Not one of the four product pages we read gives the molecular weight of its own PDRN — and that is the number that decides whether any of it arrives.

The injected evidence is real. In a split-face trial of 27 people, the side injected with polynucleotide scored higher on a standard aesthetic scale at 16 weeks and had smoother skin by 28 weeks [2]. All of it was done with a needle. In the US, the injectable is not approved for cosmetic use, while the serum is legal because cosmetics need no approval [1]. So the treatment that produced the evidence is the one you cannot buy there, and the bottle you can buy has no published evidence of its own.

Newer work. In July 2026, a randomised split-face trial in 31 women tested a topical PDRN eye cream against retinol for four weeks and measured how far it penetrated; the PDRN side came out ahead [5]. It was a different preparation in a different bottle, but it suggests the delivery problem may not be permanent.

What people say. A writer who tested 15 of these serums came away positive, and the dermatologist she asked called topical PDRN promising but still evolving [10]. A British beauty writer was blunter, arguing that rose is not close to human DNA — one writer's argument, not a finding [11]. Buyers, over and over, describe hydration and glow in the reviews we read on Cult Beauty and Skin Cupid [9]. Almost nobody describes regeneration. One Medicube reviewer said she was unsure about the salmon DNA but liked the niacinamide and peptides, which may be doing the work.

The verdict

Three buys and a wait. Anua is a good hyaluronic acid serum, and the only one honest enough to print its numbers. Numbuzin is the best value, as long as you buy it for the price rather than the "5%" on the front. Medicube is a buy for glow, if fragrance suits your skin. Rejuran is a wait, not a no: it is a premium price for a reputation earned by an injectable, and the day it publishes delivery data for the bottle, that changes.

Buy these serums for hydration and glow; the regeneration claims belong to the needle, not the bottle.

Worth knowing

• "Ppm" and "%" on the front can mean different things. Turn the bottle round and read the ingredient list.
• The Medicube 10,000 ppm figure is a retailer claim, not a brand statement.
• Fragrance: present in Medicube; Numbuzin is fragrance-free.
• Numbuzin comes in two versions, 5% and 10%, so check which one you are buying.
• If you are considering injectable PDRN or polynucleotides, talk to a clinician; that is a medical treatment, not a skincare choice.

Watch the video

The full breakdown, with the ppm ladder on screen, is here: Salmon DNA Serums: I Checked the Science on 4 Viral Products.

Sources

1. Dermatology Times, "Social Media Mythbusters: PDRN Serums", 2026
2. Lee YJ et al., split-face polynucleotide versus hyaluronic acid filler (n=27, injected), Journal of Dermatological Treatment, 2022
3. Squadrito F et al., pharmacology and clinical use of PDRN, Frontiers in Pharmacology, 2017
4. Rho NK et al., injectable polynucleotide in Korean practice, Journal of Cosmetic Dermatology, 2024
5. Topical medium-length PDRN, split-face trial (n=31), PLOS ONE, 10 July 2026, doi:10.1371/journal.pone.0350905
6. Anti-Aging Efficacy of Low-Molecular-Weight PDRN from Paeonia lactiflora, 2025, PMC12785872
7. PDRN in dermatology, review, Applied Sciences 15(19):10437, 2025
8. Rejuran Cosmetics, US launch announcement, March 2026
9. Product pages and ingredient lists: Skin Cupid, Cult Beauty, John Lewis, BPerfect, Sephora, DermFND, read 6 September 2026
10. The Daily Beast, review of PDRN serums quoting a board-certified dermatologist, 2026
11. British Beauty Blogger, on rose PDRN, 2026

Every claim above is sourced in the text. Prices are what we paid, on the date shown. We buy what we test; nothing is gifted, and nothing is sponsored.