Collaborative Research: EAGER--Condensed Matrix Assisted Laser Desorption Ionization (cMALDI) Towards Online Detection of Viral Nucleic Acids and Proteins in Aerosols

这个高风险、高回报的EAGER项目的重点是开发一种仪器，可用于在现场实时检测与大气气溶胶相关的病毒和病毒片段。这一仪器的研制是朝着回答与亚微米粒子有关的病毒在大气中传播模式的若干问题迈出的第一步。希望该仪器最终能在空气传播病毒监测中得到应用。研制的仪器是缩合基质辅助激光解吸电离气溶胶飞行时间质谱仪（cMALDI-ATOFMS）。该仪器有望使用飞行激光解吸/电离飞行时间质谱法测量含有病毒或病毒片段的空气气溶胶的尺寸分辨数分数。这项工作包括开发和优化一个三级冷凝系统（cMALDI），以将亚微米级的病毒颗粒生长到空气动力学和光学大尺寸，这是ATOFMS光学检测所需的。使用cMALDI系统的实验室实验将用于开发利用蛋白质和核酸的混合物纳入单分散亚微米到超微米测试颗粒的校准。这些混合物将被雾化并用作调整ATOFMS设置以进行生物分子检测的测试。单个的、裸露的病毒将通过电喷雾雾化，这样来自病毒的信号就能与背景分子清楚地区分开来。如果成功，这将是首次通过质谱法在单个气溶胶颗粒水平上检测病毒。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。

This high-risk, high-reward EAGER project is focused on developing an instrument that can be used to detect viruses and viral fragments associated with atmospheric aerosols in real time in the field. The development of this instrument represents the first step towards answering a number of questions about the modes of atmospheric transport for viruses associated with submicron particles. It is hoped that the instrument will eventually find application in airborne virus monitoring. The instrument to be developed is a condensation matrix assisted laser desorption ionization-aerosol time-of-flight mass spectrometer (cMALDI-ATOFMS). This instrument is expected to provide measurements of the size-resolved number fraction of airborne aerosols containing viruses or viral fragments, using in-flight laser desorption/ionization-time-of-flight mass spectrometry. The effort includes the development and optimization of a three-stage condensation system (cMALDI) to grow submicron, virus-laden particles to the aerodynamically and optically large sizes, needed for ATOFMS optical detection. Laboratory experiments using the cMALDI system will be used to develop calibrations utilizing mixtures of proteins and nucleic acids incorporated into monodisperse submicrometer-to-supermicrometer test particles. These mixtures will be nebulized and used as tests to tune the ATOFMS settings towards biomolecular detection. Individual, bare viruses will be aerosolized via electrospray, such that the signal from a virus is clearly distinguished from background molecules. If successful, these will be the first measurements enabling virus detection at the single aerosol particle level via mass spectrometry.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.