A novel surface phenomenon will be explored for the quantitative detection of nucleic acid hybridization. We will construct a relatively inexpensive instrument, which can attain a sensitivity limit comparable to the existing methodologies, without the use of dyes, or radioisotopes. As part of the phase l research, we will use the existing hardware to test affinity of DNA to a specifically prepared surface. This test is a necessary step in the operation of the instrument. We will also measure the binding of the complementary DNA to assess the detection limit, sensitivity and the issue of non-specific binding. In Phase Il, the signal to noise ratio will be optimized and a prototype of the device specifically designed for hybridization detection will be built. The complete hybridization protocol will be tested on the new instrument. If the proposed research is successful, the new instrument can perform routine nucleic acid hybridization detection for molecular biology research and clinical laboratory tests.