Extended-gate AlGaAs/GaAs HEMT for accurate cardiac troponin I antigen detection in clinical human serum

In this study, we developed extended-gate AlGaAs/GaAs HEMT sensors for accurate cTnI detection in serum. During the research, we found that blocking reagents whose molecule sizes are as large as the sizes of the target biomolecules can greatly improve the accuracy of detection. Based on this, the range of linear detection was significantly broadened, from 100 fg ml−1 to 1 ng ml−1. Additionally, 30y extended-gate HEMT sensors help to achieve accurate detection of cTnI in serum. The lowest relative errors of the 30y-structure were about 4%, which are greatly reduced as compared with the errors when using conventional sensors.