Fan Jiayi, Wu Lei, Wang Jing, Bian Xiaoying, Chen Chongchong, Chang Kuan
Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical & Material Engineering, Jiangnan University, Wuxi 214122, China.
Jiangnan Institute of Beauty Research, Wuxi 214122, China.
Molecules. 2025 Mar 6;30(5):1182. doi: 10.3390/molecules30051182.
Photoaging is common and represents one of the primary pathways for hair damage in daily life. Hydrolyzed keratin, which is usually derived from wool and consists of a series of polypeptide molecules, has been investigated as a UV damage prevention ingredient for hair care. Scanning Electron Microscopy (SEM) and fluorescent penetration experiments verified that hydrolyzed keratin can deposit on the hair cuticles to form a film and partly penetrate into the hair cortex. This film played as a UV reducer and helped hair resist surface damage and maintain a sleek and healthy morphology after UV radiation. Surprisingly, it was found that hydrolyzed keratin treatment combined with subsequent UV radiation could significantly improve the tensile properties of hair. For hydrolyzed-keratin-treated hair, tensile strength was maintained after UV radiation, while, as a comparison, it decreased by 14.32% for untreated hair. This phenomenon is explained by a UV-induced degradation-penetration mechanism. During UV radiation, an increase in free amino acid content and conductivity was observed for the hydrolyzed keratin solution, demonstrating photodegradation into smaller peptides and amino acids. The degradation of hydrolyzed keratin allowed it to more easily enter the interior of the hair cortex, thereby enhancing its tensile properties by enhancing the chemical bonds.
光老化很常见，是日常生活中头发受损的主要途径之一。水解角蛋白通常来源于羊毛，由一系列多肽分子组成，已被研究作为一种用于头发护理的防紫外线损伤成分。扫描电子显微镜（SEM）和荧光渗透实验证实，水解角蛋白可以沉积在头发角质层上形成一层膜，并部分渗透到头发皮质中。这层膜起到了紫外线减少剂的作用，帮助头发抵抗表面损伤，并在紫外线辐射后保持光滑健康的形态。令人惊讶的是，发现水解角蛋白处理后再进行紫外线辐射可以显著改善头发的拉伸性能。对于经水解角蛋白处理的头发，紫外线辐射后拉伸强度得以保持，而作为对比，未处理的头发拉伸强度下降了14.32%。这种现象可以通过紫外线诱导的降解-渗透机制来解释。在紫外线辐射过程中，观察到水解角蛋白溶液的游离氨基酸含量和电导率增加，表明其光降解为更小的肽和氨基酸。水解角蛋白的降解使其更容易进入头发皮质内部，从而通过增强化学键来提高其拉伸性能。
