The key ingredient in vitamin C serums is L-ascorbic acid, a pure form of vitamin C, says Joshua Zeichner, MD, a board-certified dermatologist in New York City.This type of serum penetrates more , A nourishing, creamy serum: Sunday Riley C.E.O. 15% Vitamin C Brightening Serum An affordable formula with proven ingredients: Timeless Skin Care 20% C + E Ferulic Acid Serum, Why We Love It: Easily one of Drunk Elephant’s most-loved products, C-Firma Fresh Day Serum is surely one of the industry's best-selling vitamin C serums. The acclaimed cruelty-free elixir is , Tatcha Violet C Serum includes two types of vitamin C: 10% vitamin C derivative (ascorbyl tetraisopalmitate) and 2% vitamin C. (ascorbic acid). The serum also contains Japanese beautyberry, a powerful antioxidant that aids in the stabilisation and efficiency of vitamin C., The 16 Best Vitamin C Serums for Glowing and Even Skin, According to Experts These dermatologist-recommended serums fight hyperpigmentation and so much more. By Genesis Rivas Updated: May 15, 2025 2:04 PM EDT, Remember, vitamin C works best in tandem with ferulic acid and vitamin E, so before making any new purchase, study labels. Last, a serum with less than 10% concentration of vitamin C will not reap the skin-brightening, collagen-boosting benefits you want..