Patent ID: 8877144

Claim:
An apparatus for processing a biological sample by performing one or more processing steps, the apparatus comprising: a container comprising a gravitational drain formed by a bottom plate that slopes at an angle of greater than 0 degrees and less than 90 degrees with a horizontal plane on which the apparatus is disposed, and at least three side walls, wherein the bottom plate is configured to receive at least one sample carrier; a block enclosed within the container, the block comprising a sample side surface arranged substantially parallel to the bottom plate of the container, wherein the block is movable within the container in relation to the sample carrier; and a liquid supply for supplying an amount of a liquid that is to be applied to the biological sample for the one or more processing steps; and further wherein the container and the block define a processing chamber that provides a variable confined volume that can be varied by changing a distance of the sample side surface of the block from the bottom plate of the container.