ABSTRACT
The Micro Force Balance consists of an optical microscope, a micromanipulation stage, a video camera and an image analyzer system (Fig 1).
The optical microscope allows either transmitted or reflected illumination to be used and has a theoretical maximum resolution of 0.45 µm. On the stage two micromanipulators are employed to hold micropipettes, to the ends of which particles are attached. A third micropipette is then used to add bridging liquid between the particles. The force of the liquid bridge is calculated by measuring how much a pre-calibrated pipette bends as the particle are separated. The breaking sequence is captured on a video
image analysis software system and is used to measure the volume of the bridge and the separation distance at which the bridge ruptures.
