Effect Of Particle Morphology On Performance Of An Electrostatic Air-Liquid Interface Cell Exposure System For Nanotoxicology Studies

Particle morphology can affect the performance of an electrostatic precipitator air-liquid interface (ESP-ALI) cell exposure system and the resulting cell toxicity. In this study, three types of monodisperse aerosols - spherical sucrose particles, nonspherical align soot aggregates, and nanosilver aggregates/agglomerates - were selected to evaluate the collection efficiency at flow rates ranging from 0.3 to 1.5 lpm. To quantify the particle morphology, the fractal dimensions (D-f ) of the tested aerosols were characterized. The penetration of fine particles (d(p) = 100-250 nm) under different operating conditions was correlated with a characteristic exponential curve using the dimensionless drift velocity (V-c/V-avg,V-r ) as the scaling parameter. For nanoparticles (NPs, d(p) nm) with different particle morphologies, the particle penetrations in the ESP-ALI were similar, but their diffusion losses were not negligible. In contrast, for fine particles, the collection efficiency of soot nanoaggregates (D-f = 2.29) was higher than that of spherical sucrose particles. This difference might be due to the simultaneous influences of the electric field-induced and flow field-induced alignment. Furthermore, based on Zhibin and Guoquan's Deutsch model, a quadratic equation was applied to fit the experimental data and to predict the performance of the ESP-ALI.