Rapid Electrical Concentration and Detection of Cardiac Biomarker Troponin I

Abstract

Rapidity and sensitivity are crucial factors for diagnosis of heart attack, and cardiac Troponin I (cTnI) is currently a clinical standard for its diagnosis. We present a labelfree, rapid and highly sensitive single-walled carbon nanotube (SWCNT) immunosensor of cTnI using two pairs of electrodes for its dielectrophoretic concentration and electrical detection via resistance measurement. Despite many examples of the dielectrophoretic capture of bacteria and DNA, protein dielectrophoresis (DEP) is in its infancy and the DEP of cTnI has never been explored before. Detection time was greatly reduced(~1 min) by using dielectrophoretic concentration and sensitivity was measured to be ~0.6 pg mL-1.