Multiplexed electrochemical detection of three cardiac biomarkers cTnI, cTnT and BNP using nanostructured ZnO-sensing platform

Aim: Development of a label-free multiplexed point-of-care diagnostic device for a panel of cardiac biomarkers - cardiac troponin-T (cTnT), troponin-I (cTnI) and B-type natriuretic peptide (BNP). Methods: A nonfaradaic electrochemical immunoassay designed with anisotropic high surface area ZnO nanostructures grown using low-temperature hydrothermal methods was selectively immobilized with capture antibodies. Multiplexed detection in human serum using ZnO nanostructures based on complementary electrochemical measurement techniques - electrochemical impedance spectroscopy and Mott-Schottky. Results: Linear signal response for detection of three biomarkers in human serum with dynamic range of 1 pg/ml-100 ng/ml and limit of detection at 1 pg/ml and low signal response to background interferences was achieved. Conclusion: First demonstration of simultaneous detection of three cardiac biomarkers in clinically relevant range with sensor's analytical performance and linear response of detection showed potential utility in screening clinical samples for early diagnosis of acute myocardial infarction and chronic heart failure.