在溶液中的D-氨基酸分析中,使用了质子化腺的光化学特性
Riyo Nakanishi1, Akimasa Fujihara2
1Department of Chemistry, Osaka Metropolitan University, Osaka, 558-8585, Japan.
概括
质子化腺可以区分气相和溶液相中的胺基因. 这种性识别方法使得能够精确地对histidine enantiomers进行定量分析.
科学领域:
- 分析化学 分析化学
- 化学物理 化学物理
- 生物化学 生物化学
背景情况:
- 在生物系统和药物开发中,体识别至关重要.
- 气相研究为分子相互作用提供了独特的见解.
- 质子化腺素在性区分方面的潜力以前未被探索.
研究的目的:
- 为了研究质子化腺对丁反体的奇拉识别能力.
- 为了探索性歧视的气相机制.
- 将这种气相发现应用于溶液中的定量分析.
主要方法:
- 电散射电离和冷离子陷的双重质谱学.
- 紫外线光解离谱在100K. 在紫外线光解离谱.
- 分析腺和丁反体的与键结合的质子集群.
- 使用单个产品离子光谱和校准曲线进行定量分析.
主要成果:
- 在D-histidine和L-histidine enantiomers之间区分的质子化腺.
- 在278nm时,H+ (氨酸) (D-氨酸) 集群的强度是H+ (氨酸) (L-氨酸) 的两倍以上,相比于H+ (氨酸) (L-氨酸).
- 氨酸部分在质子化氨酸中的电子激发状态促进了奇拉识别.
- 在溶液中成功量化确定了L-histidine和D-histidine的摩尔分数.
结论:
- 质子化腺在气相中具有固有的性识别能力.
- 腺素和D-ribose之间的甘氨酸键是这种识别的关键.
- 气相奇拉区分方法适用于溶液中的定量分析.
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