Acrylamide Hydrogel-Modified Silicon Nanowire Field-Effect Transistors for pH Sensing

Gangrong Li; Qianhui Wei; Shuhua Wei; Jing Zhang; Qingxi Jin; Guozhi Wang; Jiawei Hu; Yan Zhu; Yun Kong; Qingzhu Zhang; Hongbin Zhao; Feng Wei; Hailing Tu

doi:10.3390/nano12122070

Acrylamide Hydrogel-Modified Silicon Nanowire Field-Effect Transistors for pH Sensing

Nanomaterials (Basel). 2022 Jun 16;12(12):2070. doi: 10.3390/nano12122070.

Authors

Gangrong Li^{1

2

3}, Qianhui Wei^{1

2}, Shuhua Wei⁴, Jing Zhang⁴, Qingxi Jin^{1

2

3}, Guozhi Wang^{1

2

3}, Jiawei Hu⁴, Yan Zhu¹, Yun Kong¹, Qingzhu Zhang⁵, Hongbin Zhao^{1

2}, Feng Wei¹, Hailing Tu^{1

2}

Affiliations

¹ State Key Laboratory of Advanced Materials for Smart Sensing, GRINM Group Co., Ltd., Beijing 100088, China.
² GRIMAT Engineering Institute Co., Ltd., Beijing 101407, China.
³ General Research Institute for Nonferrous Metals, Beijing 100088, China.
⁴ School of Information Science and Technology, North China University of Technology, Beijing 100144, China.
⁵ Advanced Integrated Circuits R&D Center, Institute of Microelectronic of the Chinese Academy of Sciences, Beijing 100029, China.

Abstract

In this study, we report a pH-responsive hydrogel-modified silicon nanowire field-effect transistor for pH sensing, whose modification is operated by spin coating, and whose performance is characterized by the electrical curve of field-effect transistors. The results show that the hydrogel sensor can measure buffer pH in a repeatable and stable manner in the pH range of 3-13, with a high pH sensitivity of 100 mV/pH. It is considered that the swelling of hydrogel occurring in an aqueous solution varies the dielectric properties of acrylamide hydrogels, causing the abrupt increase in the source-drain current. It is believed that the design of the sensor can provide a promising direction for future biosensing applications utilizing the excellent biocompatibility of hydrogels.

Keywords: FET sensor; acrylamide hydrogel; pH sensitive; silicon nanowire.

Grants and funding

This work was supported by the National Natural Science Foundation of China (Grant No. 52172158), the Youth Fund Project of GRINM (Grant No. 66272030), Key R & D project of Guangdong Province (Grant No. 2021B0909060001), and Technology Innovation Fund of GRIMAT (Grant No. 57272101).