在循环极化莱曼-α光照射下,在 Racemic 氨基酸膜中出现光学活动和表面形态变化的出现
Masahiro Kobayashi1, Jun-Ichi Takahashi2, Hiroshi Ota3
1National Institute for Fusion Science, Toki, Japan.
Chirality
|November 11, 2024
概括
用真空紫外线 (VUV) 光诱导分子变化和改变表面微观结构的环极光 (CPL) 对氨酸薄膜的辐射. 这些发现提供了关于生命同类性起源的见解.
科学领域:
- 天体生物学 天体生物学
- 生命的起源研究 生命的起源研究
- 摄影化学的使用.
背景情况:
- 同化性,即生物分子中偏好单一的同化性,是生命起源的一个基本难题.
- 循环极化光 (CPL) 是实现这种合对称性破坏的拟议机制.
- 在CPL下了解生物分子的光反应对于生命起源场景至关重要.
研究的目的:
- 为了研究在真空紫外线 (VUV) CPL辐射下种族氨酸薄膜的光反应.
- 探索莱曼-α CPL作为太空中的不对称光源的潜力,以诱导奇拉不对称.
- 分析VUV CPL对氨酸分子结构和薄膜形态学的影响.
主要方法:
- 在UVSOR-III同步光源上开发一个VUV CPL辐射系统.
- 用莱曼-α CPL (121.6 nm) 辐射种族氨酸薄膜样本.
- 使用循环二重化 (CD) 光谱和液态色谱-质谱法 (LC-MS) 分析变化.
主要成果:
- 在CD光谱 (180-240nm) 中,VUV CPL辐射诱导了异性质,不同于enantiopure alanine.
- LC-MS检测到较大的分子的形成,包括寡合性氨酸添加物.
- 薄膜微观结构的显著变化,形成圆形网络聚合物 (约. 100nm),也可以观察到.
结论:
- VUV CPL辐射诱导氨酸薄膜中的分子和形态修饰.
- 这些变化,包括寡合化和改变的微观结构,可以解释观察到的CD光谱差异.
- 需要对VUV CPL下的固态生物分子光反应进行进一步的研究,以支持宇宙同质性情景.
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