Electrospray–differential mobility analysis of bionanoparticles

Electrospray–differential mobility analysis (ES–DMA) is a versatile technique used to aerosolize bionanoparticles and measure their electrical mobility at ambient conditions. ES–DMA is similar to electrospray–mass spectrometry (ES–MS), but measures the effective particle size, rather than mass. It has a wide range of applications and nominally can be used to characterize biomolecules and nanoparticles ranging in size from a few nanometers (∼3 nm) to several hundred nanometers, to obtain multimodal size distributions in minutes. Although both the ES and the DMA are mature technologies, they are finding increased use in combination to characterize particles in liquids. In this paper, we review ES–DMA, and how it has recently been used to characterize bionanoparticles such as polymers, proteins, viruses, bacteriophages and nanoparticle–biomolecule conjugates.