CAREER: Reaction dynamics study of biomolecular ions with electronically excited singlet molecular oxygen using guided-ion-beam scattering and direct dynamics trajectory methods

在这个由化学系化学结构、动力学和机理项目支持的项目中，纽约城市大学皇后学院刘建波教授和他的研究小组将研究氨基酸和二肽等生物分子与一种称为单线态分子氧（^ 1o2）的活性氧的反应。单线态氧是在自然界中由正常的氧分子在来自太阳的可见光/紫外线的存在下产生的。生物分子与单线态O2的反应不仅从化学反应动力学的角度来看是有趣的，而且也是一个重要的话题，因为它与衰老和疾病（例如白内障和某些皮肤癌）等生物过程以及大气和海洋中生物物种的癌症和光化学转化的光动力疗法有关。刘教授和他的团队将对生物分子与单线态O2的反应进行系统的研究，旨在从分子水平上了解反应机理和反应动力学/动力学。实验系统的范围从无水的气相分离生物分子，到附着少量水分子的气相水合生物分子，再到液态水中的生物分子。采用的实验技术包括引导离子束散射和电喷雾电离质谱。由于光敏法生产单线态O2经常产生臭氧和其他不良物质，使结果复杂化，刘教授的实验室将采用化学技术生产纯单线态O2，用于与生物分子的反应。实验工作将辅以理论计算，包括从头算电子结构计算和直接动力学轨迹模拟。刘教授的研究项目不仅将培养纽约市立大学的研究生和大四本科生，还将通过他参与的昆斯伯勒大桥项目和MARC-U*STAR项目，让高中生参与其中，该项目旨在吸引社区大学生和少数民族学生参与科学研究。此外，为了配合纽约市立大学大学预科暑期研究项目，来自当地高中的学生将在刘的实验室工作，他们的成果将转化为具有竞争力的科学展览研究项目。这个研究项目也被整合到刘教授的正式课程教学中。他将使用他的研究设备在物理化学和仪器分析实验室开发新的实验（例如，离子轨迹模拟和碰撞诱导的分子解离）。

In this project supported by the Chemical Structure, Dynamics, and Mechanisms Program of the Division of Chemistry, Professor Jianbo Liu and his research group at the Queens College of the City University of New York will study the reaction of biomolecules such as amino acids and dipeptides with a reactive oxygen species called singlet molecular oxygen (^1 O2). Singlet O2 is generated in nature from normal oxygen molecules in the presence of visible/ultraviolet light from the sun. The reaction of biomolecules with singlet O2 is not only interesting from the standpoint of chemical reaction dynamics, but is also an important topic because of connections to biological processes such as aging and diseases (e.g. cataracts and some skin cancers), as well as photodynamic therapy for cancer and photochemical transformations of biological species in the atmosphere and oceans. Professor Liu and his team will conduct a systematic study of the reaction of biomolecules with singlet O2, aimed at achieving a molecular level understanding of the reaction mechanism and reaction kinetics/dynamics. The experimental systems range from isolated biomolecules in the gas phase in the absence of water, through gas-phase hydrated biomolecules with a few water molecules attached, to biomolecules in liquid water. The experimental techniques employed include guided-ion-beam scattering and electrospray ionization mass spectrometry. Since the photosensitization method for producing singlet O2 often produces ozone and other undesirable species that complicate the results, Professor Liu's laboratory will employ a chemical technique to generate pure singlet O2 for reactions with biomolecules. The experimental work will be complemented by theoretical calculations, including ab initio electronic structure calculations and direct dynamics trajectory simulations.Professor Liu's research program will train not only graduate and senior undergraduate students at CUNY, but will also involve high school students through his participation in the Queensborough Bridge Program and MARC-U*STAR Program, which engage community college students and minority students in science. Also, in coordination with the CUNY pre-college summer research program, students from local high schools will work in the Liu laboratory, and their results will be translated into competitive science fair research projects. This research program is also integrated into Professor Liu's formal course teaching. He will use his research equipment to develop new experiments (e.g., simulations of ion trajectories, and collision-induced dissociation of molecules) in Physical Chemistry and Instrumental Analysis Laboratories.