Fluorescent lifetime imaging of atmospheric aerosols: a direct probe of aerosol viscosity
Fluorescent lifetime imaging of atmospheric aerosols: a direct probe of aerosol viscosity
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DOI：
10.1039/c3fd00041a
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发表时间：
2013-01-01
影响因子：
3.4
通讯作者：
Pope, Francis D.
中科院分区：
文献类型：
--
作者：
Hosny, Neveen A.;Fitzgerald, Clare;Pope, Francis D.
大气气溶胶颗粒的粘度影响许多关键的物理和化学颗粒性质，如组成和反应性。然而，测定气溶胶颗粒的微观粘度是一项不平凡的任务。我们报告了一种在各种模型气溶胶系统中成像粘度的新方法，该方法基于称为分子转子的粘度敏感荧光团的荧光寿命测定。我们报道了与相对湿度相关的NaCl和蔗糖气溶胶吸湿性的粘度变化，以及油酸气溶胶臭氧分解过程中与反应相关的粘度变化。分子转子的荧光寿命成像显微镜（FLIM）在理解气溶胶重要的基本特性方面显示出巨大的希望，这些特性可以通过气溶胶粒子进行时间依赖和空间变化。
The viscosity of atmospheric aerosol particles affects a number of key physical and chemical particle properties, such as composition and reactivity. However, determination of the microscopic viscosity of aerosol particles is a non-trivial task. We report a new method of imaging viscosity in a variety of model aerosol systems, based on a fluorescence lifetime determination of viscosity-sensitive fluorophores termed molecular rotors. We report the viscosity changes associated with the relative humidity dependent hygroscopicity of NaCl and sucrose aerosols, as well as reaction dependent changes in viscosity during ozonolysis of oleic acid aerosols. The Fluorescence Lifetime Imaging Microscopy (FLIM) of molecular rotors shows great promise in understanding important fundamental aerosol properties, which can be both time-dependent and spatially variable through the aerosol particle.