Nanohmics, Inc. and Ambion, Inc. working in consortium with Dr. Susan Kauzlarich at the University of California Davis and Dr. Lynn Loo at the University of Texas at Austin propose to develop a Nanocomposite Organic Field-Effect Transistor (NanOFET) multiplex microarray platform for compact, label-free detection of oligonucleotide assays. The proposed method will involve the development of ultrathin, high carrier mobility, polymeric/semiconductor composites consisting of doped nanoparticles and conducting polymers. The proposed geometry provides a means to measuring both charge effects and localized temperature change resulting from the hybridization reaction. Nucleotide anchors will be immobilized to the surface of the nanoparticles and be embedded in the composite active layer. These organized composite active layers will be deposited using a single step transfer technique over the entire surface of the NanOFET array. Lithographically patterned source and drain contacts will serve as independent immobilization sites for extension of each probe oligonucleotide in the library.
The specific aim of the proposed research is to develop a high throughput analysis platform that does not require a secondary labeling step. In this regard, microarray analysis with multiple targets can be performed with a single sample aliquot and be analyzed using compact reader devices. The proposed method will involve the first attempt to integrate oligo photocoupling chemistry with a field effect transistor array in the preparation of active structures with embedded probe anchors. The development of FET geometry with the proposed novel active semiconducting layer will provide a means for scaling FET arrays to production microarray devices as opposed to other geometries that have limited scalability. The microarray will operate as a label-free, direct electrical transduction platform and be analyzed by compact reader instrumentation, including field applications, where it may be possible to perform real time disease state, pathogen or biothreat detection on oligonucleotide samples. ? ? ?