Development of an Electron Paramagnetic Resonance Spectrometer with Zeptomole Sensitivity

在化学测量和成像项目的支持下，以及原子、分子和光学实验物理项目的部分共同资助下，匹兹堡大学的Gurudev Dutt博士和他的团队正在研究小体积的过程，比如在细胞内部或纳米级材料（如电池电极材料）内。由于增加的表面积效应，这些过程通常与散装溶液中的过程明显不同。统计物理、热力学和动力学可以在这些领域发挥巨大的作用，因此开发可以进入这些领域的传感和成像技术至关重要。具体来说，Dutt小组正在开发工具，为仅涉及几百个亚微米空间分辨率分子的系统提供一个非常快（纳秒到微秒）的功能动力学窗口。高通量平台可以在一系列受到各种化学或物理刺激的通道中提供图像。需要解决的多方面的挑战为研究生和本科生提供了教育和培训的机会，他们构成了未来的科学和专业劳动力。PI还向当地一所高中的学生讲授光学光谱学，作为他们大三化学项目的基础，并将与他们的科学老师一起创建一个关于“化学量子传感和量子计算”的暑期讲习班。这些拓展工作的长期目标是通过为低收入青年接受高等教育做好准备，打破世代贫困的循环。本研究计划的主要目标是创建下一代生物化学和生物物理学探索平台，以研究室温条件下纳米级电子自旋动力学。在这个项目的三年里，Dutt团队将在一个光学寻址的微流体装置中测量电子自旋标记生物分子的电子顺磁共振（EPR）光谱，该装置具有zeptomole灵敏度（10-21摩尔），可以完全控制温度和磁场。他们将设计并制造一种基于金刚石的芯片，该芯片带有量子传感器，可以在室温下从电子自旋的小集合中获得可重复的EPR光谱，最终达到单自旋的水平。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Chemical Measurement and Imaging Program and partial co-funding from the Atomic, Molecular, and Optical Experimental Physics program, Dr. Gurudev Dutt and his team at the University of Pittsburgh are investigating processes in small volumes, such as inside a cell or within nanoscale materials such as battery electrode materials. These processes often differ markedly from those in bulk solutions due to increased surface area effects. Statistical physics, thermodynamics, and dynamical considerations can play an outsized role in these domains – it is therefore critical to develop sensing and imaging technologies that can access this domain. Specifically, the Dutt group is developing tools to provide a window into the very fast (nanosecond to microsecond) functional dynamics of systems involving just a few hundred molecules with sub-micron spatial resolution. The high-throughput platform can provide images in an array of channels being subjected to various chemical or physical stimuli. The multi-faceted challenges to be tackled provide educational and training opportunities for graduate and undergraduate students that form the future scientific and professional workforce. The PI also presents lectures about optical spectroscopy to students at a local high school to serve as a scaffold for junior year chemistry projects, and will work with their science teachers to create a summer workshop on “Quantum Sensing and Quantum Computing for Chemistry”. The long-term aim of these outreach efforts is to break the cycle of generational poverty by preparing low-income youth for higher education. The main objective of this research program is to create a next-generation biochemistry and biophysics exploration platform to study nanoscale electron spin dynamics under room-temperature conditions. During the three years of this project, the Dutt team will measure electron paramagnetic resonance (EPR) spectra of electron spin-labeled bio-molecules with zeptomole sensitivity (10-21 moles) in an optically addressable microfluidic device, with full control over temperature and magnetic field. They will design and construct a diamond-based chip with quantum sensors that can obtain reproducible EPR spectra on small ensembles of electron spins at room temperature, eventually reaching the level of single spins.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.