In-situ investigation of aerosol particles by atomic force microscopy

In-situ imaging of aerosol particles deposited on mica in the TM-AFM liquid cell has been performed in order to study their dissolution behavior. The results show that the implementation of in-situ experiments is very useful for obtaining information on the physical and chemical behavior of individual particles. Experiments were carried out using ammonium sulfate and soot-like particles as test aerosols. Water soluble fractions can be easily distinguished from insoluble fractions. This can also be utilized to proof the existence of internally mixed particles. These model experiments are an important basis for further investigations on airborne particles involving other solvent systems and time resolved measurements.