Abstract

Multiplex Detection of Sepsis Biomarkers Enabled by Closed Bipolar Electrochemistry with Optical Readout

Paul Bohn, Arthur J. Schmitt Professor of Chemical and Biomolecular Engineering and Professor of Chemistry and Biochemistry, University of Notre Dame

Sepsis syndrome affects close to 1,000,000 patients annually in the US alone. Of these ca. 30%, predominantly from the pediatric and geriatric populations, do not survive. In current practice, diagnosis is carried out using symptomatic indicators, which is problematic given the similarity of the symptoms to those of patients with influenza. What is needed is a rapid and accurate test that can distinguish where a patient is along the sepsis continuum, starting with systemic inflammatory response syndrome and ending at severe septic shock. We are developing microfluidically-enabled multiplex sensors capable of simultaneously discerning the presence and level of multiple biochemical markers of sepsis syndrome. The sensor relies on a unique assay, in which an electrochemical detection reaction is amplified by redox cycling in an analytical cell. This, in turn, is coupled to a complementary redox-cycled optical readout reaction in a separate reporter cell. Significant flexibility in design means that the readout can be tuned to the desired concentration range of the analyte, colorimetric readout for relatively high level metabolites, e.g. lactate, metal-deposition shifts in optical transmission of metamaterials for higher sensitivity, and fluorigenic reactions where maximum sensitivity is required, e.g. cytokines.