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Title: Synthesis of Ni–TiO Nanocomposites as Enzyme–Less, Amperometric Sensors for the Electrooxidation of Glucose
The simple synthesis of a Ni–TiO2nanocomposite supported on Vulcan carbon (XC–72 R) for the electrooxidation reaction of glucose is reported. Four transition metal weight ratios were synthesized and characterized. Cyclic voltammetry studies in 0.1 M NaOH demonstrate that the four metal catalysts can effectively oxidize 1 mM glucose, with the 3:1 (60%) Ni to Ti nanocomposite yielding the highest current. The 60% Ni–TiO2/XC72R catalyst was used to construct an enzyme–less, chronoamperometric sensor for glucose detection in an alkaline medium. Using 50μM aliquots of glucose at a potential of +0.7 V (vs Hg/HgO), the sensor responded rapidly (<3 s), provided a sensitivity of 3300μA mM−1cm−2, detection limits of 144 nM (Signal/Noise = 3), and excellent selectivity and reproducibility. The glucose aliquot concentrations were then increased to 1 mM to mimic physiological blood conditions of 1–20 mM. At a potential of +0.7 V (vs Hg/HgO), the sensor continued to respond rapidly (<1 s), showed a sensitivity of 273.7μA mM−1cm−2, detection limits of 3.13μM (S/N = 3), and excellent selectivity and reproducibility. The catalyst also exhibited an ideal anti–poisoning capability to free chloride ions and negligible signals towards other interfering species.  more » « less
Award ID(s):
2018740
PAR ID:
10474220
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOP Science
Date Published:
Journal Name:
ECS Advances
Volume:
2
Issue:
2
ISSN:
2754-2734
Page Range / eLocation ID:
026502
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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