Figure 1: Diagram of variables investigated in the current experiment. Linker length: the distance from the microarray surface was varied; linker identity: nucleobase (adenine, cytosine, guanine, or thymine) was used to tether aptamers to the surface; direct labeling method: fluorescent reporter dye conjugated directly to the target molecule is incubated with aptamer microarray; indirect labeling method: biotinylated-target is added to microarray, followed by a short dye-streptavidin incubation with aptamer microarray. Following incubation, all microarrays were washed and imaged and the data was extracted in order to link fluorescence intensity location with aptamer sequence. Nucleobase structures were created using VIDA, part of OpenEye software.