title: Parallel differential mobility analysis for electrostatic characterization and manipulation of nanoparticles and viruses.
abstract: The electrophoretic mobility of charged, airborne nanoparticles (NPs) or macromolecules and their specific complexes opens new avenues for their analysis and handling. The newly developed parallel differential mobility analyzer in combination with an electrostatic particle sampler enables not only the characterization of bio-NPs, but even their sampling while preserving their bioactivity (e.g., the enzyme activity of galactosidase). Precondition for the applicability of this technique is a well-defined charging status of the NPs in question. This charge conditioning can be achieved by means of a radioactive source, Po-210, even if the yield in terms of charged particles is low for sub-20-nm particles and the aging of the source influences the size spectra measured. Nevertheless, this technique enables size-defined sampling and enrichment, combined with real-time measurement of the size of both NPs and viruses. Furthermore, it allows determination of the number of attached biospecific antibodies, thereby providing information about the surface coverage of viruses by antibodies.
authors.affiliation: Vienna University of Technology, Institute of Chemical Technologies and Analytics, Vienna, Austria.
authors.forename: Günter
authors.initials: G
authors.lastname: Allmaier
authors.affiliation: University of Vienna, Faculty of Physics, Boltzmanngasse 5, Vienna, Austria.
authors.forename: Anne
authors.initials: A
authors.lastname: Maißer
authors.affiliation: Vienna University of Technology, Institute of Chemical Technologies and Analytics, Vienna, Austria; University of Vienna, Faculty of Physics, Boltzmanngasse 5, Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Laschober
authors.affiliation: University of Natural Resources and Life Sciences, Department of NanoBiotechnology, Vienna, Austria.
authors.forename: Paul
authors.initials: P
authors.lastname: Messner
authors.affiliation: University of Vienna, Faculty of Physics, Boltzmanngasse 5, Vienna, Austria.
authors.forename: Wladyslaw W
authors.initials: WW
authors.lastname: Szymanski
keywords: Antibody; Bio-NP; Differential mobility analyzer; Electrophoretic mobility; Electrostatic particle sampler; GEMMA; Gas-phase electrophoretic mobility molecular analyzer; Macromolecule; Nanoparticle; Parallel differential mobility analyzer; Virus