NSF East Asia and Pacific Summer Institute (EAPSI) for FY 2013 in China

这一行动资助了密歇根工业大学的道格拉斯·史密斯于2013年夏天在北京理工大学中国教授的数学和物理科学领域开展一个研究项目。该项目的标题是“基于纳米颗粒的荧光传感器，用于测量活细胞中的酸性细胞内pH。”主持会议的科学家是彭思平博士。细胞内的pH在细胞、酶和组织的活动中起着许多关键作用，包括增殖和凋亡、离子转运、内吞作用和肌肉收缩。细胞功能障碍通常与细胞器(线粒体、溶酶体等)的pH值异常有关。监测活细胞内的pH变化对于研究细胞内化途径也很重要，如吞噬、内吞和受体配体内化。这个家伙在他的家实验室(密歇根理工大学)合成了一系列新的荧光传感器。大学)。传感器的几个特点(无细胞毒性、高细胞渗透性和长寿命的细胞内荧光)使pH传感器成为检测完整细胞内pH变化的优越候选者。其他市面上可以买到的pH传感器没有这些功能。因此，传感器为在多个时间点(小时)对完整细胞进行实时成像提供了新的实验机会，从而增加了了解正常和癌细胞生长过程中细胞内变化的新工具。这些传感器的末端乙炔/叠氮可“点击”官能团很容易获得，因此可以使用“点击”化学方法快速构建传感器分子库。该项目利用这种方法来制备多个基于纳米颗粒的荧光传感器。EAPSI奖学金的更广泛影响包括为研究员提供美国以外的第一手研究经验；介绍各自所在地的科学、科学政策和科学基础设施；以及了解社会、文化和语言。这些活动符合NSF的目标，即在其科学家、工程师和教育工作者的职业生涯早期为国际合作进行教育，从而确保拥有一支具有全球意识的美国科学队伍。

This action funds Douglas Smith of Michigan Technological University to conduct a research project in the Mathematical and Physical Sciences area during the summer of 2013 at Beijing Institute of Technology in Beijing, China. The project title is "Nanoparticle-based Fluorescent Sensors for Measurement of Acidic Intracellular pH in Living Cells." The host scientist is Dr. Si-ping Pang.Intracellular pH plays many critical roles in cell, enzyme and tissue activities, including proliferation and apoptosis, ion transport, endocytosis, and muscle contraction. Cellular dysfunction is often associated with abnormal pH values in organelles (mitochondria, lysosomes, etc.). Monitoring pH changes inside living cells is also important for studying cellular internalization pathways, such as phagocytosis, endocytosis, and receptor ligand internalization. The Fellow synthesized a series of new fluorescent sensors in his home lab (Michigan Tech. Univ.). Several features of the sensors (absence of cytotoxicity, high cell permeability, and long-lived intracellular fluorescence) make the pH sensors superior candidates for examining intracellular pH alterations in intact cells. Other commercially available pH sensors do not exhibit these features. Accordingly, the sensors offer novel experimental opportunities for live-imaging in intact cells over multiple time points (hours), and thus add a new tool in understanding intracellular alterations in normal and cancerous cell growth. The easily accessible terminal alkyne/ azido "clickable" function groups of these sensors offer the possibility of rapidly constructing sensor molecule libraries using "click" chemistry. This project exploits this approach to prepare multiple nanoparticle-based fluorescent sensors. Broader impacts of an EAPSI fellowship include providing the Fellow a first-hand research experience outside the U.S.; an introduction to the science, science policy, and scientific infrastructure of the respective location; and an orientation to the society, culture and language. These activities meet the NSF goal to educate for international collaborations early in the career of its scientists, engineers, and educators, thus ensuring a globally aware U.S. scientific workforce.