Disclosed are polymeric constructs that can advantageously be utilized in a wide variety of fluid contact devices. The constructs include two or more polymeric materials, at least one of which includes reactive functionality so as to preferentially interact with an analyte of interest. The polymeric constructs include the reactive materials in discrete areas of the devices, so as to provide the reactive functionality in a patterned array across a fluid contacting surface of the device. The reactive functionality can be provided in a macro-, a micro-, or a nano-patterned array, depending upon the specific parameters of the formation process. The devices can be utilized in separation protocols as well as other applications involving controlled fluid flow across a reactive surface.