APPARATUS FOR DETECTING PARTICLES

摘要

Apparatus for detecting particles in a liquid, comprises an evanescent optical sensor having an electrically conducting layer, and means associated therewith for providing an electric field at or adjacent the sensor surface. Preferably, the optical sensor is a surface bound sensor based on a metal-clad leaky waveguide structure. A DC potential applied to the metal layer and a parallel counter electrode provides a uniform electric field, which drives deposition of the particles on the sensor surface. Alternatively, an alternating potential applied to a electrically conducting layer configured as an electrode and counter electrode induces an electro-osmotic bulk flow in the liquid which drives deposition of the particles on the sensor surface.