Blue Light and Premature Skin Aging – New In Vivo Test Method

The harmful effects of blue light rays on the skin are increasingly becoming the focus of the cosmetics industry and consumers.   So far, only a few in vivo test methods for measuring the effects of blue light on the skin have been described in the literature.   Direct detection methods that show the immediate effects of blue light on the collagen network of the skin are still missing. In   the work presented here, a new in vivo test method for measuring the effect of blue light on the skin is presented.   The skin of volunteer subjects was irradiated with a light source with a narrow emission spectrum and low-dose blue light (6 J/cm2).   Before irradiation, and 1 hour respectively 24 hours after irradiation, we were able to detect the increase in MMP-1 concentration   and the decrease in type 1 procollagen in the blister fluid of the suction blisters. We were able to visualize the collagen network   with the help of scanning electron microscopy (SEM) on the underside of the suction blister roofs and quantitatively evaluate it   with the help of an image analysis. Here, too, after blue light treatment, there was an increasing degradation of the collagen   fibers as well as a decrease in the length of the collagen strands.   The presented study can be used as an effective in vivo test method for products that want to reduce the negative effects of blue   light on the skin and reduce premature skin aging