黄素的UV-A诱导的光异构化和光二构化:一种离子移动性质谱学研究
Piyali Chatterjee1, Subhra Sankar Dutta1, Megha Agarwal1
1School of Chemical Sciences, Indian Association for the Cultivation of Science, 2A Raja S C Mullick Road, Jadavpur, Kolkata 700032, India.
The journal of physical chemistry. A
|January 11, 2024
概括
当黄素暴露在紫外线下时,它会经历新的光化学转化,包括光异构化和光二构化. 了解这些反应对于优化黄素的反应至关重要.
科学领域:
- 摄影化学的使用.
- 有机化学 有机化学
- 生物化学 生物化学
背景情况:
- 从黄中提取的黄素在癌症治疗的光动力疗法 (PDT) 中充当光敏剂.
- 库尔库的光化学命运,对于其治疗效果至关重要,仍然不太了解.
- 研究黄素的光化学转化对于推进PDT应用至关重要.
研究的目的:
- 阐明黄素在水甲醇混合物中的新型光化学反应途径.
- 在紫外线照射下识别和描述黄素光化学变化的产物.
- 评估这些反应对黄素在光动力学治疗中的作用的重要性.
主要方法:
- 用350nm紫外线照射黄素溶液的辐射.
- 使用漂移管离子移动性质谱学 (DTIMS),高性能液态色谱学 (HPLC) 和碰撞诱导解离 (CID) 的综合分析.
- 实验碰撞截面 (CCS) 值与异构体识别理论预测的比较.
主要成果:
- 鉴定两种黄素光异构体,这些光异构体是通过跨-cis异构化产生的.
- 通过 [2+2] 循环添加和光氧化 (H2-损失) 产物进行光二分化的证据.
- 使用DTIMS和电子结构理论,成功对光异构体进行区分.
结论:
- 黄素表现出各种光化学反应,包括光异构化,光二氧化和光氧化.
- 已识别的光异构体可以作为二聚体和H2损失产品的前体.
- 了解这些途径可以提高黄素在PDT中作为光敏感剂的应用.
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