A Potentiometric Sensor Based on a Copper(II) Ion Composite for Vitamin C Determination in Urine

Author(s)

Rodrigues, Kelly B. ^{[1, 2]} ; Fonseca, Fernando L. A. ^[1] ; Fernandes, Julio C. B. ^{[2, 3]}

Affiliation

^[1] Fac ABC Med 821, Dept Clin Med, Clin Lab, Principe Gales Ave, BR-09060650 Santo Andre, SP - Brazil

^[2] Municipal Univ Sao Caetano do Sul 50, Santo Antonio St, BR-09521160 Sao Caetano do Sul, SP - Brazil

^[3] Fed Univ Western Para UFOPA, Inst Educ Sci, S-N Marechal Rondon, BR-68040070 Santarem, PA - Brazil

• Document type: Journal article
• Source: JOURNAL OF ANALYTICAL CHEMISTRY; v. 75, n. 8, p. 1086-1093, AUG 2020.
• Web of Science Citations: 0

Abstract

We developed an all-solid-state sensor for monoascorbate ion based on a composite containing copper(II) ions (5 wt %), graphite and epoxy resin. The sensor presented super-Nernstian response at room temperature under continuous bubbling of oxygen gas in sample. The detection limit of the sensor was 0.02 mM and its linear range was between 0.05 and 1.5 mM with upper limit of quantification equal to 3 mM. The leaching out effect of the active component from composite was estimated less than 11 mu g of copper(II) sulfate per day under continuous diffusion process in deionized water. Photomicrographs of the electrode surface did not show the presence of salt particles on the surface indicating that copper(II) ions could be intercalated in graphene layers. Attenuated total reflectance infrared spectrum demonstrated this possibility. The sensor was successfully applied to the in vitro determination of L-ascorbic acid in urine. (AU)

• FAPESP's process: 14/04596-8 - Early acute kidney injury biomarkers study in type 2 diabetes
• Grantee: Fernando Luiz Affonso Fonseca
• Support Opportunities: Regular Research Grants