School of Pharmacy, Nanjing Medical University, Nanjing, Jiangsu, 211126, P. R. China.
State Key Laboratory of Analytical Chemistry for Life Science and School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210023, P. R. China.
Chem Asian J. 2021 Dec 13;16(24):4049-4052. doi: 10.1002/asia.202101057. Epub 2021 Oct 22.
The generation of free radicals is a key process in the formation and the collapse of the bubbles in water, however, the direct and dynamic observation of the radicals in this process at single bubbles has never been achieved. Here, the hydroxyl (OH ) and oxygen (O ) radicals at single oxygen bubbles are continuously traced using chemiluminescence (CL), in which these radicals at the bubble react with the surrounding luminol in the solution emitting the light. Varied increase trends of luminescence are observed in the generation of a bubble, floating, short parking at the water/air interface and the final explosion, revealing the complexity in the distribution of radicals at the bubble unprecedentedly. Despite more radicals are observed at the bubble generated at a deep position under the water for the stabilization, almost the same amount of radicals are included in the bubbles that is independent on the water pressure during the production of the bubble. This rich information collected from the dynamic study of bubbles illustrates the complicated generation and distribution process of radicals at the bubbles, and will facilitate the understanding of the function about the bubbles.
自由基的产生是水内气泡形成和破灭的关键过程，然而，在单个气泡内自由基的直接动态观测却从未实现过。在这里，使用化学发光（CL）连续追踪单个氧气气泡内的羟基（OH）和氧（O ）自由基，在这个过程中，气泡内的这些自由基与周围溶液中的鲁米诺反应发出光。在气泡的产生、漂浮、在水/气界面短暂停留和最终爆炸过程中，观察到发光的变化趋势，前所未有的揭示了自由基在气泡内的分布复杂性。尽管在水下深处生成的气泡由于稳定而观察到更多的自由基，但在气泡产生过程中，包含在气泡内的自由基数量几乎相同，与水压无关。从气泡的动态研究中收集到的丰富信息说明了自由基在气泡内产生和分布的复杂过程，有助于理解气泡的功能。
