Recent advances in nanomaterial-modified electrical platforms for the detection of dopamine in living cells

Abstract

Dopamine is a key neurotransmitter that plays essential roles in the central nervous system, including motor control, motivation, arousal, and reward. Thus, abnormal levels of dopamine directly cause several neurological diseases, including depressive disorders, addiction, and Parkinson's disease (PD). To develop a new technology to treat such diseases and disorders, especially PD, which is currently incurable, dopamine release from living cells intended for transplantation or drug screening must be precisely monitored and assessed. Owing to the advantages of miniaturisation and rapid detection, numerous electrical techniques have been reported, mostly in combination with various nanomaterials possessing specific nanoscale geometries. This review highlights recent advances in electrical biosensors for dopamine detection, with a particular focus on the use of various nanomaterials (e.g., carbon-based materials, hybrid gold nanostructures, metal oxides, and conductive polymers) on electrode surfaces to improve both sensor performance and biocompatibility. We conclude that this review will accelerate the development of electrical biosensors intended for the precise detection of metabolite release from living cells, which will ultimately lead to advances in therapeutic materials and techniques to cure various neurodegenerative disorders.

Keywords: Conductive polymers; Dopamine; Electrical detection; Gold nanostructure; Graphene.

Fig. 1

Schematic illustration representing recent advances in nanomaterial-modified EC platforms for the detection of dopamine from living cells

Fig. 2

a Schematic illustration representing the 3D-N-doped mesoporous nanosheets-based DA sensing platform. b Amperometric responses of the platform showing its selectivity toward DA. c Amperometric data of DA secreted from PC12 cells with (brown graph) or without (green graph) stimulation of DA release, with permission from [52]; Copyright 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Fig. 3

a Schematic illustration showing an oxidised polypyrrole/sodium dodecyl sulphate-modified multi-walled carbon nanotube (OPPy/SDS-CNT) electrode for the detection of DA. b DPV graphs of the OPPy/SDS-CNT electrode with several concentrations of DA (5 nM–10 µM). c Regression analysis of the current peaks obtained from b. d Amperometric currents of DA were released from cells using the OPPy/SDS-CNT electrode. e Cytotoxicity test of the OPPy/SDS-CNT electrode using the MTT assay. With permission from [54], Copyright 2019 Elsevier B.V

Fig. 4

a Schematic illustration of the fabrication processes for micro pyramid platform structures. b Selectivity test of dopamine with interfering substances. c The amperometric responses of micro pyramid platform with several concentrations of DA (500 µM–10 nM). With permission from [59], Copyright 2020, Analytical chemistry

Fig. 5

a Schematic illustration showing fabrication processes of GNP-modified carbon fibre electrode. b Surface electron microscope image of GNP-modified carbon fibre electrode. c Amperometric monitoring of DA released from single PC12 cell using the GNP-modified carbon fibre electrode. The microscopic image of a single PC12 cell during amperometric detection is shown in the inset image. The red arrow represents initiation point of stimulation. With permission from [57], Copyright 2018, American Chemical Society

Fig. 6

a Schematic illustration of electrode fabrication. b The plot of fabricated electrodes with various concentrations of dopamine. c Selectivity test of dopamine against interfering substances. d The current change test with KCl stimulation (arrow points) of PC12 cells. With permission from [61]; Copyright 2019, Elsevier

Fig. 7

a Schematic illustration of the platform fabrication and culturing of PC12 cells. b The real-time amperometry test for dopamine. c The dopamine selectivity test for the fabricated platform. d The real-time amperometry test for current changes with K⁺ stimulation of a cell suspension solution. With permission from [64]; Copyright 2019, ACS applied materials and interfaces

Fig. 8

a Schematic illustration representing the carboxylated polypyrrole nanotubes (CPNTs)/Aptamer-functionalised liquid-ion gated field-effect transistor (FET)-based DA sensor. b Amperometric test of various concentrations of dopamine with two types of tubular structured-aptasensors (CPNT1 and CPNT2). c Selectivity analysis of the CPNTs/aptamer-based sensor against interfering substances. d The amperometric response of the CPNTs/aptamer-based sensor for monitoring dopamine exocytosis at different KCl concentrations. With permission from [65]; Copyright 2020, Scientific reports