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、高回报的渴望项目专注于开发一种仪器，可以用于在野外实时检测与大气气溶胶相关的病毒和病毒碎片。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的传播方式的一些问题迈出的第一步。希望该仪器最终能在空气传播病毒监测中得到应用。将开发的仪器是凝聚基质辅助激光解吸电离-气溶胶飞行时间质谱仪(cMALDI-ATOFMS)。预计该仪器将使用飞行中激光解吸/电离飞行时间质谱仪，测量含有病毒或病毒碎片的空气中气溶胶的尺寸分辨数分数。这项工作包括开发和优化三级冷凝系统(CMALDI)，以将亚微米、携带病毒的颗粒生长到ATOFMS光学探测所需的空气动力学和光学大尺寸。使用cMALDI系统的实验室实验将用于开发校准，利用掺入单分散亚微米到超微米测试颗粒中的蛋白质和核酸的混合物。这些混合物将被雾化并用作测试，以调整ATOFMS设置以进行生物分子检测。单个裸露的病毒将通过电喷雾被雾化，这样来自病毒的信号就明显地与背景分子区分开来。如果成功，这些将是第一次能够通过质谱学在单个气溶胶颗粒水平上检测病毒的测量。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.