Design, Synthesis, and Characterization of DNA Origami for the Detection of Biomolecules

Analysis of nucleic acid sequences and proteins is a powerful tool in medicine, allowing for the diagnosis of disease and identification of genetic mutations. We propose a platform using DNA origami, a technique for creating nanoscale shapes out of DNA. This DNA origami device is bistable, capable of reconfiguring between two states of “open” and “closed,” dependent on the presence of an analyte of interest, such as a specific DNA sequence or protein. In solution, this conformational change can be determined by an electrophoretic gel shift. To detect this conformational change on a surface we can observe a structural change by atomic force microcopy. More specifically, we can detect this structural change on an electroactive surface by utilizing the large DNA assemblies to integrate signaling molecules for 30X amplification from a single molecule binding event. These signaling molecules donate electrons at different kinetic rates based on moving the signaling molecule closer or farther away from the surface and can be detected through electrochemical methods. Both binding domains and signaling molecules are integrated into a single DNA origami device eliminating many laborious steps required for a standard immunoassay such as sandwich ELISA, which require several different components to be assemblies and purification. The implications of this work will foster novel innovations for point of care testing for disease.