Characterization and separation of nanoparticles through electrical and geometrical trapping and manipulation

Nanoparticles are becoming increasingly important in biomedical applications, electrophoretic ink displays, as well as in food and cosmetics. This does imply that the nanoparticles in these applications become increasingly complex and that their development requires accurate characterization. In addition, it is often crucial to screen properties of individual nanoparticles in complex and polydisperse samples, to measure them for a sufficiently long time, or to separate specific nanoparticles from a complex sample. This project will develop nanostructured devices with integrated electrodes that enable electrical trapping, characterization of nanoparticles on a particle-to-particle level and nanoparticle separation. The fabrication of the devices is based on e-beam lithography. With these devices, the charge and charging mechanism of nanoparticles in nonpolar liquids doped with surfactant will be investigated, relevant to novel electrophoretic ink displays. To measure nanoparticles in liquids with a higher conductivity, relevant to biomedical applications, active electrical trapping is proposed. Finally, by combining nanostructured landscapes and active electrical transport, nanoparticles will be separated based on their charge and size. In this way, the proposed research contributes to a next generation of nanoparticle-based lab-on-a-chip devices and to improved biomedical and nanotechnological applications.