Design and mechanism of photocurrent-modulated graphene field-effect transistor for ultra-sensitive detection of DNA hybridization

Field-effect transistors (FET) using low-dimensional materials has attracted attention for detection of DNA hybridization. Here, we proposed a photocurrent-modulated FET sensor, where the I-photocurrent(gate) + I-photocurrent(DNA) dramatically enhance the response signal, I-current, compared to a tradi-tional FET sensor. The proposed sensor successfully detects DNA signals with a limit of detection (LOD) down to attomolar concentrations that is nearly 100x lower than a traditional FET sensor. The sensing mechanism is postulated and discussed. The results suggest that photo-coupled modulation opens new avenues for further development of the FET in biosensing applications. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a photocurrent-modulated FET sensor for DNA hybridization detection was proposed, achieving a detection limit down to attomolar concentrations. The sensor significantly enhances the response signal compared to traditional FET sensors, opening new avenues for further development in biosensing applications.