Magnetic Graphene Field-Effect Transistor Biosensor for Single-Strand DNA Detection

• Published in: Nanoscale research letters Vol. 14; no. 1; pp. 248 - 8
• Main Authors: Sun, Jinjin, Xie, Xiaohui, Xie, Ke, Xu, Shicai, Jiang, Shouzhen, Ren, Junfeng, Zhao, Yuefeng, Xu, Huaqiang, Wang, Jingjing, Yue, Weiwei
• Format: Journal Article
• Language: English
• Published: New York Springer US 24.07.2019; Springer Nature B.V; SpringerOpen
• Subjects: Aptamers; Biomolecules; Biosensor; Biosensors; Chemical vapor deposition; Chemistry and Materials Science; Complementary DNA; Deoxyribonucleic acid; DNA; Field effect transistors; Field-effect transistor; Glass substrates; Graphene; Impedance; Magnetic; Magnetic fields; Magnetic nanobeads; Materials Science; Molecular Medicine; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Organic chemistry; Semiconductor devices; Signal to noise ratio; Single-stranded DNA; Transistors; Magnetic nanobeads; Magnetic; Graphene; Field-effect transistor; Biosensor; DNA
• ISSN: 1931-7573; 1556-276X
• DOI: 10.1186/s11671-019-3048-1

Herein, a magnetic graphene field-effect transistor biosensor was prepared through the transfer of a chemical vapor deposition graphene film onto a glass substrate to produce a sensing film and conductive channel. By fixing 1-pyrenebutanoic acid succinimidyl ester onto graphene film as an anchor, a probe aptamer was immobilized on the graphene film in order to capture magnetically labeled complementary single-stranded DNA. Our experiments showed that, within a periodic magnetic field, the biosensor impedance exhibited a periodic oscillation, the amplitude of which was correlated to the complementary DNA concentration. Based on this principle, the magnetic graphene field-effect transistor was utilized to detect single-stranded DNA with detection limition of 1 pM. The results were rationalized using a model wherein the magnetic force causes the DNA strand to bend, thereby resulting in magnetic nanobeads/DNA modulation of the double conductive layer of graphene transistors. Furthermore, since a periodic magnetic field could be introduced to produce a periodic impedance changes of MGFETs, sampling integration could be used to improve the signal-to-noise ratio efficiently by increasing the number of periods of the external magnetic field. Therefore, a novel biosensor for DNA detection with high sensitivity has been presented in this work. Based on the detection principle, this system may also be a potential tool for detecting other bio-molecules, cells, etc.