Differential Mobility Particle Sizers for Nanoparticle Characterization

Differential mobility particle sizers (DMPSs) are instruments for online sizing gas-borne particles in submicrometer and nanometer diameter ranges. The aerosol charger, the differential mobility analyzer (DMA), and the particle concentration detector are three essential components in DMPSs. In the past four decades, the design of DMAs has evolved into a variety of modern versions to extend their sizing limits, especially in lower detectable size limits. The DMAs are now capable of classifying or sizing particles in the diameters down to 1.0 nm. This article gives a brief overview of state-of-the-art DMAs particularly designed for classifying particles with sizes down to sub-10 nm.