Differential-mode HEMT-based biosensor for real-time and label-free detection of C-reactive protein
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- 作者：Hee Ho LeeAuthor Vitae ; Myunghan BaeAuthor Vitae ; Sung-Hyun JoAuthor Vitae ; Jang-Kyoo Shin ; jkshin@ee.knu.ac.kr" class="auth_mail" title="E-mail the corresponding authorAuthor Vitae ; Dong Hyeok SonAuthor Vitae ; Chul-Ho WonAuthor Vitae ; Jung-Hee LeeAuthor Vitae
- 关键词：GaN ; HEMT ; Biosensor ; Differential-mode ; CRP
- 刊名：Sensors & Actuators: B. Chemical
- 出版年：2016
- 出版时间：29 October 2016
- 年：2016
- 卷：234
- 期：Complete
- 页码：316-323
- 全文大小：2115 K
文摘
In this paper, we have investigated the characteristics of the differential-mode high electron mobility transistor (HEMT)-based biosensor. An Au-gate HEMT is the sensing device that reacts with biomolecules, whereas the Pt-gate HEMT is the dummy device used in the differential-mode detection circuit. Both the biosensing HEMT (Bio-HEMT) and reference HEMT (Ref-HEMT) were biased by a Pt quasi-reference electrode (QRE). The Pt QRE was used to replace the bulky conventional reference electrode. The binding of 11-mercaptoundecanoic acid, CRP-antibody, and CRP caused a variation in Bio-HEMT gate surface potential, which was confirmed by X-ray photoelectron spectroscopy. Moreover, we measured the variation of output voltage with light intensity and temperature, which was eliminated as a common-mode signal by the differential-mode measurement technique. Therefore, this technique can improve the detection limit in low CRP concentration. The output voltage of the sensor system is nonlinearly proportional to the CRP concentration from 0.01 ng/mL to 1000 ng/mL. These results indicated that the Bio-HEMT/Ref-HEMT/QRE could be applied to a portable biomolecule detection system.