an array of valves are arranged in n columns and m lines and which are each designed to control a fluid flow in an associated flow channel in a lab - on - a - chip system . the array includes at least two valves , every column having not more than one valve and every line having from zero to n valves . a device is used for actuating the valves . the valves are pressure - actuated . to produce the device , the flow channels are arranged in accordance with the arrangement of the valves .