由于周期性延伸而导致与年龄相关的曲发的内部结构变化:一项IR光谱学研究
Naoya Fuse1, Yukako Matsue1, Shigeaki Morita2
1Beauty Care Laboratory, Home Products Campany, Kracie, Ltd., Yokohama, Japan.
International journal of cosmetic science
|January 9, 2025
概括
循环延伸导致与年龄相关的曲头发的结构变化,包括脂质转移和二硫化物键裂解. 这些转变导致解开的α螺旋转化为β结构,影响头发的曲率.
科学领域:
- 材料科学 材料科学 材料科学
- 生物物理学的生物物理.
- 频谱学是一种光谱学.
背景情况:
- 与年龄相关的头发曲,称为"YUGAMI"头发,涉及复杂的结构变化.
- 了解这些转变对于开发有效的护发策略至关重要.
研究的目的:
- 为了研究循环延伸引起的与年龄相关的曲头发的结构变化.
- 通过先进的光谱技术,阐明导致头发曲线变化的分子机制.
主要方法:
- 使用了红外 (IR) 光谱,特别是减弱总反射IR (ATR-IR) 显微镜.
- 多变量曲线分辨率 (MCR) 和二维相关谱 (2DCOS) 用于光谱分析.
- 头发纤维在0.3-N应变水平下经历了循环延伸,达到500个循环.
主要成果:
- 在0.3-N菌株的周期延伸增加了125周期后的CH2和C=O信号,并在曲发中增加了225周期后的SO3H信号.
- 在相同的条件下,在直发中没有观察到任何显著的建筑修改.
- 2D相关谱检测显示S-SO3H和SO3H信号增加,其次是α螺旋转化为β结构.
结论:
- 由于周期性延伸,与年龄相关的曲头发的内部转变过程发生在三个不同的步骤中.
- 这些步骤涉及表面脂质转移,二硫化键裂变 (C-S和S-S裂变),以及α螺旋转化为β结构.
- 这些发现提供了关于管理由重复的机械压力引起的头发曲的见解,例如日常理.
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