巨大的,可调和和可逆的pH变化
Laura Wimberger1, Shyamal K K Prasad1, Martin D Peeks1
1School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia.
Journal of the American Chemical Society
|November 30, 2021
概括
新的梅洛酸光开关能够控制光的pH值变化. 这些分子开关允许精确,远程调节pH依赖的过程,为先进的应用提供可调节的恢复时间.
科学领域:
- 摄影化学
- 超分子化学
- 化学生物学
背景情况:
- 精确控制pH值对于许多生物和化学过程至关重要.
- 现有的pH调节方法往往缺乏非侵入性或远程控制功能.
- 分子光开关为光触发的环境变化提供了潜在的解决方案.
研究的目的:
- 开发用于光诱导pH调节的新型梅洛酸光开关.
- 研究这些光开关引起的pH变化的参数.
- 建立光开关驱动的pH变化的预测模型.
主要方法:
- 合成和描述新的美洛酸光开关.
- 使用450nm光来诱导pH变化的辐射实验.
- 超快速的短暂吸收光谱用于研究反应动态.
- 基于实验参数的数学模型的开发.
主要成果:
- 达到可逆的总体pH值变化高达3.2个单位 (pH值6. 5至3. 3).
- 可调节和可预测的热恢复时间表.
- 确定影响pH调节的关键参数:溶解度,酸度,平衡度和光效应.
- 确定过渡性美洛异构体的量子产量和寿命 (30-550 ns).
结论:
- 酸光开关可以有效地控制光的大量pH值.
- 开发的模型根据实验确定的参数准确地预测pH值的变化.
- 量子产量不是观察到的pH切换效率的限制因素.
相关概念视频
pH
The potential of hydrogen (pH) is a measure of the acidity or basicity of a water-based solution determined by the concentration of hydronium ions (H3O+). In one liter of pure water at neutral pH, there are 1×10−7 moles of hydronium ions. However, the extensive range of hydronium ion concentrations present in water-based solutions makes measuring pH in moles cumbersome. Therefore, a pH scale was developed to convert moles of hydronium ions into the negative logarithm of the hydronium ion...
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pH plays a critical role in maintaining normal cellular activities. It helps maintain the structure and function of various proteins, dictates the charge on cellular membranes, and is crucial for metabolic reactions inside the cell. Moreover, cells use the energy from the proton motive force to generate ATP.
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Under physiological conditions, the cytosolic pH is slightly more acidic than the extracellular pH. However, cells must prevent further acidification of their cytosol to...
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