Opto Field-Effect Transistors for Detecting Quercetin–Cu<sup>2+</sup> Complex
Pradhana Jati Budhi Laksana,
Li-Chu Tsai,
Chang-Cheng Lin,
Kuei-Shu Chang-Liao,
Mathew K. Moodley,
Chii-Dong Chen
Affiliations
Pradhana Jati Budhi Laksana
Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan
Li-Chu Tsai
Institute of Organic and Polymeric Materials, National Taipei University of Technology, Taipei 10608, Taiwan
Chang-Cheng Lin
Institute of Organic and Polymeric Materials, National Taipei University of Technology, Taipei 10608, Taiwan
Kuei-Shu Chang-Liao
Department of Engineering and System Science, National Tsing Hua University, Hsinchu 30013, Taiwan
Mathew K. Moodley
Discipline of Physics, School of Chemistry and Physics, College of Agriculture, Engineering and Science, University of KwaZulu-Natal, Durban 4000, South Africa
Chii-Dong Chen
Institute of Physics, Academia Sinica, Taipei 11529, Taiwan
In this study, we explored the potential of applying biosensors based on silicon nanowire field-effect transistors (bio–NWFETs) as molecular absorption sensors. Using quercetin and Copper (Cu2+) ion as an example, we demonstrated the use of an opto–FET approach for the detection of molecular interactions. We found that photons with wavelengths of 450 nm were absorbed by the molecular complex, with the absorbance level depending on the Cu2+ concentration. Quantitative detection of the molecular absorption of metal complexes was performed for Cu2+ concentrations ranging between 0.1 μM and 100 μM, in which the photon response increased linearly with the copper concentration under optimized bias parameters. Our opto–FET approach showed an improved absorbance compared with that of a commercial ultraviolet-visible spectrophotometry.
