This study details how new technology, called Confocal Raman Microspectroscopy, is being used to measure how effectively the skin’s stratum corneum is hydrated by moisturizers. In particular, the researchers were interested in how well moisturizers that contained Niacinamide affects the water gradient in the skin’s Stratum Corneum.
Further studies use this method to measure the efficacy of niacinamide containing moisturizers.
An example mass market moisturizer containing Niacinamide is Olay Regenerist Daily Regenerating Serum.
Confocal Raman microspectroscopy—A new method for measuring the effects of topical moisturizers on stratum corneum water gradient, in vivo
Paul Matts, PhD, Jonathan Crowther, PhD, Anke Sieg, PhD, Peter Blenkiron, PhD, Procter & Gamble, Egham, United Kingdom
The stratum corneum (SC) water concentration gradient is fundamental to skin’s role as a barrier, regulating its mechanical, physical, optical, and biochemical properties. Standard instruments that utilize changes in SC electrical properties to estimate SC water concentration provide simple, rapid measurements but cannot, by nature, provide true interval data as a function of depth.
Confocal Raman microspectroscopy (CRS), in contrast, is a new technique that combines the well attested method of Raman spectroscopy (the study of inelastic scattering of light, rather than its absorption) with confocal microscopy, allowing noninvasive, realtime, in vivo measures of molecular concentration profiles.
A new confocal Raman microspectrometer equipped with a fiber-coupled laser source operating at a wavelength of 671 nm was used to obtain measurements in the high wave number region (~2400-4000 cm-1). An air-cooled, high-sensitivity NIR detector system, equipped with a back-illuminated, deep-depletion CCD camera captured radiation scattered inelastically from focal planes within the skin in vivo (a high-precision, computer-controlled piezo-electric stage and objective allowing depth resolutions of less than 5 um, with oversampling).
High-wave number data were analyzed to provide semiquantitative measures of water concentration ([water]/[protein 1 water]) across the SC.
This new technique was used to study changes in SC water concentration gradients in human skin in vivo, in response to treatment with topical moisturizing products.
This poster will report the results of a blinded, randomized 3- week study in human volunteers and, in particular, the significant (P <.05), unique effects of a topical moisturizer containing niacinamide (vitamin B3) on SC water concentration gradient, as measured by CRS, in vivo. SC water gradient effects will be discussed in the context of the known SC barrier-augmentation properties of niacinamide and the utility of this new method will be compared and contrasted to existing methodology.
Author disclosure: All authors are employees of Procter & Gamble Company. Research funded by P&G Beauty.
Poster Discussion Session P404, American Academy of Dermatology, 64th Annual Meeting, March 3-7 2006, San Francisco.
Supplement to Journal of The American Academy of Dermatology, March 2006, Volume 54, Number 3.
- JAAD Poster Abstracts Online (29Mb)
- Households Products Database: Niacinamide (Vitamin B)
