ZnS Nanoparticles‐decorated Composite Graphene Paper: A Novel Flexible Electrochemical Sensor for Detection of Dopamine

Abstract

Dopamine (DA) is a significant catecholamine neurotransmitter in human metabolism, and DA is related to several critical illnesses. Accurate detection of DA is important to diagnose these diseases. Here, we demonstrated a flexible electrochemical sensor, ZnS nanoparticles decorated composite graphene paper electrode (CGPE), for the detection of DA. CGPE was prepared via mold‐casting method using ZnS/graphene oxide dispersion followed by thermal reduction treatment. The characterization of the flexible CGPE was investigated through various techniques. The electrochemical tests were carried out to study the electrocatalytic properties of CGPE against DA oxidation. Compared to graphene paper electrode (GPE), the oxidation of DA occurred at about 250 mV lower potential on CGPE, and peak current density increased about 2 times. Our sensor exhibited high sensitivity in linear range of 0.1–2300 μM of DA with a limit of detection (LOD) of 0.0042 μM. Furthermore, CGPE has selectively detected DA even in the medium containing AA and UA which are biologically active interfering molecules. Besides, the sensor showed many attractive properties such as high durability, stability, and reproducibility and it was successfully applied for the determination of DA in real samples for practical applications.

Design of metal phosphite decorated sponge materials for high‐performance flexible battery‐type supercapacitors

“…Moreover, after squeezing in Figure 2B and after placing and removing a metal disc of 100 g in Figure 2C, GSM remained an almost intact structure, demonstrating owning high flexibility and mechanical strength. In Figure 2D, GSM shows approximately 1.5 times the resistance of the GP prepared in our previous studies 46,47 . Although the electrical conductivity of GSM is lower than GP, it exhibits a higher electroactive surface area due to possessing a porous structure.…”

“…In Figure 2D, GSM shows approximately 1.5 times the resistance of the GP prepared in our previous studies. 46,47 Although the electrical conductivity of GSM is lower than GP, it exhibits a higher electroactive surface area due to possessing a porous structure.…”

Three-Dimensional ZnCo-MOF Modified Graphene Sponge: Flexible Electrode Material for Symmetric Supercapacitor

“…The SC was designed by sandwiching two PVA–KOH gel electrolyte coated ZnCo-MOF/GS electrodes among two graphene paper (GP) electrodes. Flexible, self-standing, and conductive GP electrodes were prepared as in our previous work . The two GPs with the electrode material (ZnCo-MOF/GS) applied as current collectors and the polymer gel solutions were used as both electrolyte and separator (Figure S1).…”

“…Flexible, selfstanding, and conductive GP electrodes were prepared as in our previous work. 58 The two GPs with the electrode material (ZnCo-MOF/GS) applied as current collectors and the polymer gel solutions were used as both electrolyte and separator (Figure S1). Scotch tape worked as the substrate and the protection cover.…”

Carbon-based electrochemical biosensors as diagnostic platforms for connected decentralized healthcare

“…Carbon-based nanostructures, particular CNTs and graphene, can be deposited on flexible platforms such as fabric, paper, or skin-conformable tattoos. They can be used in conjunction with other materials such as fibers of bacterial nanocellulose 96 , ZnS 87 , or AuNPs 88 and be interfaced with biomolecules to create multifunctional hybrid films. These multicomponent structures are relatively complex and their fabrication on an industrial scale is still challenging.…”