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Title: Kappa-Carrageenan/Graphene Oxide Carbon Composite Film for Electrochemical Sensing of Dopamine

A novel electrochemical dopamine sensor was fabricated based on a composite film solely consisting of kappa-carrageenan and hierarchical porous carbon drop-casted onto a glassy carbon electrode in a conventional three electrode system. Graphene oxide was synthesized in a one-step thermal conversion from base-catalyzed alkali lignin. Five ratios by mass of a novel hierarchical porous activated carbon and kappa-carrageenan were studied for dopamine quantification without synthetic binders such as polytetrafluoroethylene. Various tests were performed to explicate structure and electrochemical properties of the films. Utilizing differential pulse voltammetry for detection, the optimized 10:1 ratio system elicited a linear range of 1–250μmol l−1and a limit of detection of 0.14μmol l−1(S/N = 3). Results suggested an effective new combination of materials for non-enzymatic dopamine sensing.

 
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NSF-PAR ID:
10303506
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
The Electrochemical Society
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
167
Issue:
11
ISSN:
0013-4651
Page Range / eLocation ID:
Article No. 116506
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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