Patent ID: 8486655

Claim:
An apparatus for exposing cells to a test compound solution diffused from a point source to determine whether the test compound solution induces progressive cell activity response in the cells, the apparatus comprising: a substrate; a cover applied over the substrate such that a passageway is defined between the cover and the substrate, wherein the cover has an outer perimeter, wherein the cover defines an opening inside the outer perimeter, and wherein the opening is in fluid communication with the passageway; and a hydrophobic barrier disposed within the passageway and applied to at least one of the substrate and the cover, wherein the hydrophobic barrier defines a test site, wherein the test site is disposed within the outer perimeter of the cover when the cover is viewed from a plan view perpendicular to a plane defined by the cover, wherein the opening is disposed within the test site when the cover is viewed from the plan view, wherein the substrate, the cover, and the hydrophobic barrier are configured to contain the cells within the test site, and wherein the hydrophobic barrier provides between the substrate and the cover a gap that allows passage of gas outside of the test site while limiting passage of liquid outside of the test site.