Fabrication and characterization of aluminium interdigitated electrode hybrid with ZnO for cardiac troponin T biomarker detection

This article describes the fabrication and characterization of the aluminum interdigitated electrode (IDE) hybrid with ZnO for the detection of cardiac troponin T (cTnT) biomarker. IDE was modified with one type of probe, which is antibody for troponin T (MAb-cTnT). Initially, it starts with the fabrication process including cleaning of the wafer and followed by a conventional lithography process. Then, surface modification using ZnO as a transducer, which is responsible for signal amplifier. Then, it followed by sensor characterization using atomic force microscope (AFM) and 3D Surface (Nano) Profilometer. Surface functionalization using 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde was carried out. Next, the immobilization step was performed by adding antibody followed by antigen where the negative charges will accumulate on the surface of IDE. To evaluate the detection limit, different concentrations of antigen were applied independently from l0 to l00?ng/mL to detect the troponin T. I-V characterization was performed after each antigen concentration detection. The characterization of IDE was worked out using scanning electron microscope and atomic force microscope before and after the detection step. Here, detected the changes occurred when the attachment of different concentrations of an antigen using I-V characteristics.