Platypus Technologies LLC has added the Oris cell invasion assay kit to its line of cell-based assays. It enables viewing of cells invading a 3-D basement membrane extract (BME) in real time using a microscope or digital imaging system. Invasion can be quantitated in the same well by staining cells and using a plate reader. The kit is supplied with a BME-coated 96-well plate, a BME overlay, a detection mask, a stopper tool and cell seeding stoppers. The assay does not require cells to pass through a membrane. The cell seeding stoppers create a 2-mm detection zone where adherent cells cannot invade until after the stoppers are removed.