An assay for quantitative nucleic acid hybridization on membrane filters.

A quantitative nucleic acid hybridization assay based on a 6-mm-diameter nitrocellulose membrane filter and only 20 microliters of hybridization mixture per determination is described. As a consequence of the small ratio of hybridization volume to membrane surface, the hybridization rates reached in this system are higher than those obtained at volume to surface ratios of conventional protocols, allowing even RNA at very low concentrations to complete hybridization. This advantage, together with the high reproducibility and hybrid stability obtained with the assay, increases the ability of the filter hybridization technique to analyze quantitatively minute amounts of RNA.