IGZO-TFT Biosensors for Epstein–Barr Virus Protein Detection

A transistor-based biosensor with high sensitivity is demonstrated in this paper. The sensor is composed of a reusable In-Ga-ZnO (IGZO)-thin-film transistor (TFT) array wire connected to an external sensing pool. The TFT acts as an electrical charge transducer as well as the signal readout device. Contrast to typical approaches of employing parameters, such as transconductance, threshold voltage, or current change as the benchmark for sensitivity, we develop a model to extract the corresponding electrical changes after introducing analytes so as to mitigate device-to-device sensing variations. Using Epstein-Barr nuclear antigen-1 (EBNA-1) antibody as the example of target analyte, the IGZO-TFT biosensors are able to selectively detect 10 pg/mL of EBNA-1 antibody in the phosphate-buffered saline solution. The measurement results were cross verified with conventional enzyme-linked immunosorbent assay (ELISA). Our approach is four orders of magnitude better than the ELISA.