Department of Basic Biomedical Science, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, Sosnowiec, Poland.
Department of Skin Structural Studies, School of Pharmacy with the Division of Laboratory Medicine in Sosnowiec, Medical University of Silesia in Katowice, Sosnowiec, Poland.
Photochem Photobiol. 2017 Oct;93(5):1303-1311. doi: 10.1111/php.12786. Epub 2017 Jul 21.
Photoprotection of skin is now focused on UV radiation. The aim of this study was to evaluate in vivo cosmetic products in terms of protection against infrared radiation (IR) and propose a methodology for conducting such measurements. The directional reflectance (DR) of 12 UV filters, six care creams and two preparations containing fumed silica applied on the forearm of 36 volunteers was examined in six spectral bands for two angles of incidence. SOC-410 Directional Hemispherical Reflectometer was used to measure DR. There is very little change in DR for all spectral bands for both incident angles for both UV filters, care creams and preparations containing fumed silica. For example, for 15% of fumed silica in glycerin for the spectral band of 0.9-1.1 μm and the incident angle of 20°, skin DR prior to application was 0.543; 5 min after application was 0.533 and 30 min after application was 0.559. Both UV filters, care creams and fumed silica do not protect skin against IR. The proposed method of in vivo measurements is superior to in vitro studies which have been conducted so far because it takes into account both the refractive index at the tissue/air interface and the absorption of IR by adipose tissue.
目前，皮肤的光保护主要集中在紫外线辐射上。本研究旨在评估体内化妆品在抵抗红外线辐射（IR）方面的效果，并提出一种进行此类测量的方法。在六个光谱波段和两个入射角下，我们检查了 12 种紫外线滤光片、6 种护理霜和两种含有气相法二氧化硅的制剂在志愿者前臂上的定向反射率（DR）。SOC-410 定向半球反射计用于测量 DR。对于所有紫外线滤光片、护理霜和含有气相法二氧化硅的制剂，对于两个入射角，所有光谱波段的 DR 变化都很小。例如，对于甘油中含有 15%气相法二氧化硅的光谱波段为 0.9-1.1μm，入射角为 20°，皮肤在应用前的 DR 为 0.543；应用后 5 分钟为 0.533，应用后 30 分钟为 0.559。两种紫外线滤光片、护理霜和气相法二氧化硅都不能保护皮肤免受 IR 伤害。与迄今为止进行的体外研究相比，我们提出的体内测量方法更具优势，因为它考虑到了组织/空气界面的折射率和脂肪组织对 IR 的吸收。
