A flow cell for use in an arrayed imaging reflectometry detection system is described herein. The flow cell includes: first and second members that are secured together to define a substantially fluid-tight chamber having an inlet and an outlet, at least the second member being light transmissive; and a chip having a substrate, one or more coating layers on the substrate, and one or more probe molecules tethered to the outermost coating layer, the chip being positioned with the outermost coating layer and the one or more probe molecules thereon exposed to fluid in the chamber and facing the second member, whereby light passing through the second member is reflected by the chip.