In the miRNA plate assay, one miRNA molecule is flanked by a capture oligo and a biotinylated detection oligo through two bridge oligos. One of the bridge oligos is partially hybridized with the miRNA molecule and the capture oligo and another with the miRNA and the detection oligo. The hybrid is immobilized onto the plate through hybridization with an immobilized oligo and detected with a streptavidin-HRP conjugate and chemiluminescent substrate.

Unlike the Northern Blot Assay, the miRNA Plate Assay can distinguish small differences in the sequence of the miRNA molecule. A one nucleotide difference will prevent the formation of the hybrid, which allows miRNA isoforms to be differentiated. In addition, this assay also has a higher sensitivity compared to the miRNA Northern Blot.