Other options—like the 3-O-ethyl ascorbic acid in the Olay Vitamin C + Peptide 24 Brightening Serum—have to react with the skin before penetrating. (Think of it as L-ascorbic flying direct and ...

State Key Laboratory of Vaccines for Infectious Diseases, Center for Molecular Imaging and Translational Medicine, Xiang An Biomedicine Laboratory, School of Public Health, Xiamen University, 4221-116 ...