A Double-Deck Structure of Reduced Graphene Oxide Modified Porous Ti3C2Tx Electrode towards Ultrasensitive and Simultaneous Detection of Dopamine and Uric Acid.

Yangguang Zhu,Li Fu,Xiufen Li,Aimin Yu,Cheng-Te Lin,Qichen Tian,Chen Ye,Nan Jiang,Qiuping Wei,He Li,Dan Dai,Lidong Wu,Guosong Lai

doi:10.3390/bios11110462

Abstract

Considering the vital physiological functions of dopamine (DA) and uric acid (UA) and their coexistence in the biological matrix, the development of biosensing techniques for their simultaneous and sensitive detection is highly desirable for diagnostic and analytical applications. Therefore, Ti3C2Tx/rGO heterostructure with a double-deck layer was fabricated through electrochemical reduction. The rGO was modified on a porous Ti3C2Tx electrode as the biosensor for the detection of DA and UA simultaneously. Debye length was regulated by the alteration of rGO mass on the surface of the Ti3C2Tx electrode. Debye length decreased with respect to the rGO electrode modified with further rGO mass, indicating that fewer DA molecules were capable of surpassing the equilibrium double layer and reaching the surface of rGO to achieve the voltammetric response of DA. Thus, the proposed Ti3C2Tx/rGO sensor presented an excellent performance in detecting DA and UA with a wide linear range of 0.1–100 μM and 1–1000 μM and a low detection limit of 9.5 nM and 0.3 μM, respectively. Additionally, the proposed Ti3C2Tx/rGO electrode displayed good repeatability, selectivity, and proved to be available for real sample analysis.

Highlights

Dopamine (DA) is a catecholamine neurotransmitter in the central nervous system which contributes to various physiological functions, including memory, stimulus-response, motion control and vasodilation. [1,2]
ΛD decreased with respect to the reduced the graphene oxide (rGO) electrode modified with greater rGO mass, indicating that fewer DA biomolecules were capable of passing through equilibrium double layer (EDL) and reaching the surface of graphene oxide (GO) to achieve the voltammetric response of DA
A Ti3C2Tx/rGO heterostructure with a double-deck layer was fabricated through electrochemical reduction

Summary

Introduction

Dopamine (DA) is a catecholamine neurotransmitter in the central nervous system which contributes to various physiological functions, including memory, stimulus-response, motion control and vasodilation. [1,2]. Considering the vital physiological functions of DA and UA and their coexistence in the biological matrix, the development of biosensing techniques for their simultaneous detection with high sensitivity is desirable for diagnostic and analytical applications [6,7]. Conventional analytical methods for the simultaneous detection of DA and UA, such as high-performance liquid chromatography (HPLC), chemiluminescene, and capillary electrophoresis, have been under development for decades [8,9,10]. By using various nanomaterials modified on GCE chemically, the peak resolutions of these biomolecules have been much improved [15]. This method has been widely adopted for the recognition of DA and UA simultaneously [16,17]

Methods

Results

Conclusion