Particle manipulation with dielectric field cages
Field cages make use of the forces that high-frequency inhomogeneous electric fields exert on
particles in suspension when the objects' electric properties differ from those of the
surrounding medium. Thus, probes of sizes from several 10 µm down to several 10 nm can be
held contactless with negligible physiological stress. Although having been in use for decades
this method's possibilities are far from being exhausted. Especially the continuing
miniaturisation and standardisation suggest its application in microfluidic systems, e. g. for
single particle separation. This requires a detailed knowledge of its positioning accuracy for
different objects under different external conditions as Brownian and thermal forces
counteract the dielectric ones. The talk aims at presenting the possibilities of and limits to
measuring these forces while laying an emphasis on the extent of the field-induced heating.