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.
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Simultaneous Analysis of Ascorbic Acid, Uric Acid, and Dopamine at Bare Polystyrene Thermoplastic Electrodes
Simultaneous analysis of ascorbic acid (AA), uric acid (UA), and dopamine (DA) is desirable as they are important biomarkers that coexist in biological fluids. Electrochemical detection of these molecules can be challenging as their oxidation peaks are poorly resolved at most unmodified electrodes. Modifications are typically necessary for analysis which increase cost and complicate fabrication. Herein, inexpensive and moldable polystyrene thermoplastic electrodes (PS TPEs), that can be used for simultaneous analysis of AA, DA, and UA, without surface modification, were presented. Electrode composition was optimized for conductivity, capacitance, and electrochemistry. Detection limits were 4, 0.9, and 4 μ
- NSF-PAR ID:
- 10369516
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemElectroChem
- Volume:
- 9
- Issue:
- 11
- ISSN:
- 2196-0216
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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