Selective and sensitive electrochemical detection of glucose in neutral solution using platinum–lead alloy nanoparticle/carbon nanotube nanocomposites

• Published in: Analytica chimica acta Vol. 594; no. 2; pp. 175 - 183
• Main Authors: Cui, Hui-Fang, Ye, Jian-Shan, Zhang, Wei-De, Li, Chang-Ming, Luong, John H.T., Sheu, Fwu-Shan
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 02.07.2007; Elsevier
• Subjects: Alloys; Amperometry; Analytical chemistry; Carbon nanotube; Chemistry; Electrochemical methods; Electrochemistry; Electrodes; Exact sciences and technology; General, instrumentation; Glucose - analysis; Glucose - chemistry; Glucose detection; Hydrogen-Ion Concentration; Interferences; Lead - chemistry; Nafion; Nanocomposites - chemistry; Nanocomposites - ultrastructure; Nanoparticles - chemistry; Nanotubes, Carbon - chemistry; Nanotubes, Carbon - ultrastructure; Oxidation-Reduction; Platinum - chemistry; Platinum–lead nanoparticle; Solutions; Carbon nanotube; Amperometry; Glucose detection; Nafion; Platinum–lead nanoparticle; Interferences; Ascorbic acid; Electrochemical method; Nanoparticle; Carbon nanotubes; Selectivity; Glucose; Background noise; Coatings; Electrocatalysis; Lead alloy; Platinum alloy; Detection limit; Electrodeposition; Basic medium; Nanocomposite; Oxidation; Interference; Uric acid; Chemical sensor; Fructose; pH metering; Sensitivity; Linearity; Platinum-lead nanoparticle
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2007.05.047

Electrodeposition of Pt–Pb nanoparticles (PtPbNPs) to multi-walled carbon nanotubes (MWCNTs) resulted in a stable PtPbNP/MWCNT nanocomposite with high electrocatalytic activity to glucose oxidation in either neutral or alkaline medium. More importantly, the nanocomposite electrode with a slight modification exhibited high sensitivity, high selectivity, and low detection limit in amperometric glucose sensing at physiological neutral pH (poised at a negative potential). At +0.30 V in neutral solution, the nanocomposite electrode exhibited linearity up to 11 mM of glucose with a sensitivity of 17.8 μA cm −2 mM −1 and a detection limit of 1.8 μM (S/N = 3). Electroactive ascorbic acid (0.1 mM), uric acid (0.1 mM) and fructose (0.3 mM) invoked only 23%, 14% and 9%, respectively, of the current response obtained for 3 mM glucose. At −0.15 V in neutral solution, the electrode responded linearly to glucose up to 5 mM with a detection limit of 0.16 mM (S/N = 3) and detection sensitivity of ∼18 μA cm −2 mM −1. At this negative potential, ascorbic acid, uric acid, and fructose were not electroactive, therefore, not interfering with glucose sensing. Modification of the nanocomposite electrode with Nafion coating followed by electrodeposition of a second layer of PtPbNPs on the Nafion coated PtPbNP/MWCNT nanocomposite produced a glucose sensor (poised at −0.15 V) with a lower detection limit (7.0 μM at S/N = 3) and comparable sensitivity, selectivity and linearity compared to the PtPbNP/MWCNT nanocomposite. The Nafion coating lowered the detection limit by reducing the background noise, while the second layer of PtPbNPs restored the sensitivity to the level before Nafion coating.