Like vitamin C, vitamin E is an essential nutrient, not synthesized by humans and supplied only by oral intake. The main natural sources are fresh vegetables, vegetable oils, cereals, Figure 1 Decrease in small periorbital rhytides after daily application of vitamin C serum 15% (SkinCeuticals) for one year. Source: Photo courtesy of SkinCeuticals, Dallas, Texas, […]

As cited above in the presentation of “Mechanisms of Action,” the effcacy of topical vitamin C in neutralizing reactive oxygen species (ROS), protecting against both UVA and UVB damage, stimulating collagen synthesis, preventing UV immunosuppression, alleviating infammation, decreasing UV-induced pigmentation, and enhancing surface moisturization and skin barrier function has been repeatedly documented in controlled experiments. […]

To optimize percutaneous absorption and full activity of vitamin C, the precise formulation is of utmost importance (15). Fortunately, the skin level of vitamin C can be increased significantly by topical application. Topical absorption was proven by radioactive-labeling studies in pigs. After treatment with 10% vitamin C cream, 8.2% was found in the dermis, and […]

Vitamin C is itself not a sunscreen. Topical vitamin C protects against solar damage primarily as an antioxidant which deactivates the UV-induced free radicals, most significantly the superoxide anion, singlet oxygen, and the hydroxyl radical. Vitamin C is equally effective in protecting against both UVB (290-320 nm) and UVA (620-400 nm) (4). On both porcine […]

Vitamin C (L-ascorbic acid) is the body’s major aqueous phase antioxidant and is absolutely vital for life. All animals make their own vitamin C, except for humans and other primates, one species of Indian fruit-eating bat, and the guinea pig. In fact, a 130-pound goat synthesizes 13 grams of vitamin C per day, almost 200 […]

Karen E. Burke Department of Dermatology, Mount Sinai Medical Center and Department of Medicine, Cabrini Medical Center, New York, New York, U. S.A. INTRODUCTION In recent years, more and more cosmetic products have been formulated with antioxidants. These new products claim to “moisturize,” “protect,” and “rejuvenate” the skin. The skin naturally uses nutritional antioxidants to […]

Although careful and thorough analysis of the biological activities of a given anti­inflammatory compound using a variety of cell culture models can provide information on which inflammatory conditions a given compound is likely to be effective in treating, and although skin penetration studies will aid in the development of a formulation that theoretically delivers adequate […]

Once a compound’s size, log P value, and solubility properties in various acceptable formulation solvents have been determined, the next step in formulation development involves either measuring the penetration through skin of the compound dissolved in a single solvent or its skin penetration from simple formulations. Regardless of which approach is taken, measuring a compound’s […]

Although screening assays are critical for identifying new anti-inflammatory compounds, unless these compounds can be formulated into a topical product that delivers the compound across the stratum corneum and down to the target cells in the epidemis and/or dermis, the product will be ineffective. The steps to developing an effective topical product involve: (i) assessing […]