Cartridge comprising a biochip

Cartridge comprising a biochip, the cartridge comprising: a) a reaction chamber comprising: i) a substrate comprising an array of electrodes, each comprising: A) a self-assembled monolayer; and B) a capture binding ligand; ii) an input port for introducing reagent in which the input port allows the introduction of reagents at the bottom of the reaction chamber, comprising the reaction chamber also an outlet port at the top of the reaction chamber to minimize the introduction or retention of air bubbles upon introduction of reagents; eb) interconnections to allow the electrical connection of said electrodes to a processor.