Electrochemical Microarray on Monolith Electrode: Exploratory Research

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

Technical description MicroRNA are small 20-26 nucleotide (nt) long noncoding RNA that are effective biomarkers for a variety of diseases, including cancer, heart, obesity, and mental illness. During the last two decades, it has become evident that profiling 100s of microRNA (miRNA) molecules found in blood, urine, and tissue can lead to early diagnoses before clinical symptoms appear. Today, there is no inexpensive, reliable method for profiling microRNA that can be translated to a clinic setting. Microarray is an inexpensive technology but not reliable due to large background signal from nonspecific binding. The objective of this proposal is to explore a novel electrochemical method for profiling miRNA by measuring local redox reactions on a monolith electrode by simply scanning a laser beam over various microarray binding sites. The electrochemical (redox current) signal can potentially distinguish a perfect match between an immobilized probe and a target binding, and no redox occurs on nonspecific binding. The applied electric potential for the redox signal shifts when the binding has a single mismatch relative to a perfect binding case. The "active" biosensing based on the redox current has the potential to measure binding of target analyte molecules to immobilized probes at a sensitivity of 1 atto-moles. The electrochemical method to map local redox current density over an electrode by laser scanning is called "Scanning Electrometer for Electrical Double-layer" (SEED). Non-technical description This proposal will develop a new way to sense small pieces of nucleic acid chains that serve as biomarkers of multiple diseases including cancer. The proposal will enable detection of several different nucleic acid molecules simultaneously using electrical measurements. Importantly, instead of having to create individual electrodes for each biomarker, the authors will develop a way to detect all of the biomarkers for one electrode. This project will result in simpler, more powerful and informative way of analyzing biomarkers for human diseases.