Hyphen's 10% Vitamin C Serum Explained: Ethyl Ascorbic Acid at pH 4 in a 20 ml Bottle

Hyphen, the Mumbai-based skincare brand associated with actor Kriti Sanon, sells a 10% Vitamin C Serum with 1% vitamin E and ferulic acid that it calls an antioxidant cocktail. The product went on Hyphen's store in January 2026, when Elle India reported that it took nearly 21 months to develop and that the launch was paused more than once. It is now part of our serum comparison.

The vitamin C is 10% 3-O-ethyl ascorbic acid, a derivative rather than pure L-ascorbic acid. The brand chose it for stability and says the formula sits at about pH 4, which is less acidic than many L-ascorbic acid serums. Alongside it are 1% vitamin E and ferulic acid combined, the pairing popularised by earlier vitamin C, E and ferulic formulas. The page also lists liposomal coenzyme Q10, epigallocatechin gallate from green tea, 5% heartleaf (Houttuynia cordata) extract and 0.3% allantoin as soothing and antioxidant extras.

The bottle holds 20 ml and sells for 575 rupees on the brand store, which makes it pricier per millilitre than most 30 ml Indian vitamin C serums. The listing was marked sold out when we checked on 12 October.

Hyphen's claims come from its own in-vivo test on 30 people who used the serum twice a day for 28 days. The brand says 93% saw brighter, more even-toned skin, 90% saw hyperpigmentation fade within four weeks and 93% noticed better elasticity. It also claims 12-hour sustained release and 81% more vitamin C delivered into skin, without naming what that was compared with. No control group or published report is described on the page, so these are best treated as marketing claims.

Ethyl ascorbic acid is a reasonable choice for people who find low-pH L-ascorbic acid serums stingy. As with other derivatives, though, there is less head-to-head clinical evidence comparing it with pure vitamin C.