Devices and methods are disclosed herein for separating a supernate from a suspension. A layout of a semiconductor die is formed by generating a first integrated circuit design and copying and rotating the design so as to form three additional integrated circuit design blocks. Preferably the enzyme is inactivated by encapsulation in a pH responsive material. The first maintenance platform is configured to perform a maintenance operation on the plurality of printheads of the first printhead array when the platform is at the second position, and a first actuator is configured to move the first maintenance platform between the first position at the first side of the printhead array and the second position. These constraints can then be efficiently supported in the presence of a b-tree or another ordered index structure by identifying any inserted, updated or deleted rows and evaluating the expression in the context of those rows and any associated adjacent rows. Desirably the ammonium salts are selected from the group consisting of ammonium oxalate and ammonium tartrate.