Liu Jinxiang, Cukier Robert I, Bu Yuxiang, Shang Yuan
Institute of Theoretical Chemistry, School of Chemistry and Chemical Engineering, Shandong University , Jinan, 250100, China.
Department of Chemistry, Michigan State University , East Lansing, 48224-1322, United States.
J Chem Theory Comput. 2014 Oct 14;10(10):4189-97. doi: 10.1021/ct500238k. Epub 2014 Sep 2.
Ab initio molecular dynamics simulations reveal that an excess electron (EE) can be more efficiently localized as a cavity-shaped state in aqueous glucose solution (AGS) than in water. Compared with that (∼1.5 ps) in water, the localization time is shortened by ∼0.7-1.2 ps in three AGSs (0.56, 1.12, and 2.87 M). Although the radii of gyration of the solvated EEs are all close to 2.6 Å in the four solutions, the solvated EE cavities in the AGSs become more compact and can localize ∼80% of an EE, which is considerably larger than that (∼40-60% and occasionally ∼80%) in water. These observations are attributed to a modification of the hydrogen-bonded network by the introduction of glucose molecules into water. The water acts as a promoter and stabilizer, by forming voids around glucose molecules and, in this fashion, favoring the localization of an EE with high efficiency. This study provides important information about EEs in physiological AGSs and suggests a new strategy to efficiently localize an EE in a stable cavity for further exploration of biological function.
从头算分子动力学模拟表明,与在水中相比,过量电子(EE)在葡萄糖水溶液(AGS)中能更有效地定域为腔状状态。与在水中的定域时间(约1.5皮秒)相比,在三种AGS(0.56、1.12和2.87 M)中的定域时间缩短了约0.7 - 1.2皮秒。尽管在四种溶液中溶剂化EE的回转半径都接近2.6 Å,但AGS中的溶剂化EE腔变得更加紧凑,并且能定域约80%的EE,这比在水中的定域比例(约40 - 60%,偶尔为约80%)要大得多。这些观察结果归因于通过向水中引入葡萄糖分子对氢键网络的改变。水通过在葡萄糖分子周围形成空隙,起到促进剂和稳定剂的作用,从而以这种方式高效地促进EE的定域。这项研究提供了关于生理AGS中EE的重要信息,并提出了一种在稳定腔中高效定域EE以进一步探索生物学功能的新策略。