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Title: Employing Conductive Metal-Organic Frameworks for Voltammetric Detection of Neurochemicals
This paper describes the first implementation of an array of two-dimensional (2D) layered conductive metal–organic frameworks (MOFs) as drop-casted film electrodes that facilitate voltammetric detection of redox active neurochemicals in a multi-analyte solution. The device configuration comprises a glassy carbon electrode modified with a film of conductive MOF (M3HXTP2; M = Ni, Cu; and X = NH, 2,3,6,7,10,11-hexaiminotriphenylene (HITP) or O, 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP)). The utility of 2D MOFs in voltammetric sensing is measured by the detection of ascorbic acid (AA), dopamine (DA), uric acid (UA), and serotonin (5-HT) in 0.1 M PBS (pH=7.4). In particular, Ni3HHTP2 MOF demonstrated nanomolar detection limits of 63 ± 11 nM for DA and 40 ± 17 nM for 5-HT through a wide concentration range (40 nM – 200 µM). The applicability in biologically-relevant detection was further demonstrated in simulated urine using Ni3HHTP2 MOFs for the detection of 5-HT with nanomolar detection limit of 63 ± 11 nM for 5-HT through a wide concentration range (63 nM – 200 µM) in the presence of constant background of DA. The implementation of conductive MOFs in voltammetric detection holds promise for further development of highly modular, sensitive, selective, and stable electroanalytical devices.  more » « less
Award ID(s):
1757371
PAR ID:
10140220
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Journal of the American Chemical Society
ISSN:
0002-7863
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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