Issue 23 — November 2000

Issue 23
Category		Title		Author
Congress Report		Development of New Quality Characteristics and Resulting Optimization of Sunscreens		Marianne Brandt

Figure: 3-D-Representation of remission spectra to determine the antiinflammatory efficacy

In addition to UV light proportions, the natural sun spectrum contains considerable intensities in the visible (VIS) and near infrared (NIR) regions. In the following we would like to describe the effects of VIS/NIR irradiation on the skin in the field of sun protection and how they may contribute to the quality characterization of sunscreens. Remission spectroscopy is utilized as a measuring technique. It enables in vivo measurements of the optical properties of the skin in the entire spectrum, a direct erytheme reaction of the skin is not relevant here.

Studies of several measurements have shown that the VIS/NIR irradiation, as an addition to the COLIPA spectrum, is able to significantly reduce the minimal erythemal dosis of untreated skin (MEDu) and the sun protection factor (SPF) of sunscreens in the SPF test. These results lead to the question in how far the exisiting norms should be extended. Furthermore, they show that sun protection seems to make sense even into the VIS/NIR region.

Antiinflammatory curative or preventive studies demonstrate in how far tannins may be applied in sunscreens as a new class of active ingredients. For the natural tannin, an antiinflammatory effect as well as a preventive effect is detectable prior to erytheme formation, independent of the spectral region investigated. Tannin seems to be an interesting new active ingredient to optimize sunscreens and after-sun products.

New in-vivo quality characteristics of sunscreens and after-sun products demonstrate the remission spectroscopy used in these studies. It enables a detailed analysis of the spectral stability, the absorption behavior, water resistance, antiinflammatory and erytheme influencing properties of sunscreens in vivo.

This project (AiF-FV 11881 N) is sponsored by the Arbeitsgemeinschaft industrieller Forschungsvereinigungen "Otto von Guericke e.V.", a leading research association for the cosmetic industries in Germany.

Author

Marianne Brandt



Marianne Brandt studied Physics (majoring in Biophysics) and Medicinal Physics and Engineering (as Fernstudium). Since 1997 she has been scientific assistant at the Institut Dr. Schrader Creachem. Her field of activity includes the development and validation of various biophysical in vivo and in vitro measurement techniques.

In November 1999, the first forum of the leading research association for the cosmetic industry, FKI, took place at the Institute Dr. Schrader in Holzminden, Germany. The Institute Dr. Schrader Creachem is the research location of the FKI. Mariann Brandt reported on her current project of the association.