Extending differential electrophoresis to measure nanoparticle forces

A method is being developed for measuring interparticle forces between nanoparticles. Previously, the method of differential electrophoresis has been used to measure forces between micron size particles with different zeta potentials. The method used video microscopy to measure colloidal trajectories, and the electrokinetic equations to interpret the forces. The developments that will enable nanoparticle forces to be measured include measurements between identical spheres, as well as a method for "visualizing" the moment of breakage for smaller particles. This paper focuses on the first of these goals, measuring forces between identical particles by interpreting trajectories of colloidal triplets.