Assay devices comprising substrates functionalized to comprise probe species on multiple separate regions are provided. Ten thousand to a hundred thousand separate regions can be provided in a substrate of one square centimeter. The separate regions can comprise separate probe species, or in another embodiment, multiple different probe species can be present on each single functionalized region. The probe species are selected to be specific for binding to target species of interest in a sample. Methods and systems for making these devices are also provided. The devices are useful, for example for assaying molecules in a human sample that are reactive to a large number of different allergens placed on the substrate.
Asplund, M., M. Linford, F. Jiang