Monitoring of diclofenac with biomimetic sensor in batch and FIA systems

Author(s)

Ademar Wong ^[1] ; Luiz D. Marestoni ^[1] ; Maria D. P. T. Sotomayor ^[1]

Affiliation

^[1] Univ Estadual Paulista UNESP, Inst Quim, Dept Quim Analit, BR-14801970 Araraquara, SP - Brazil

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 25, n. 7, p. 1283-1291, 2014-07-00.

Abstract

The present work aims the development of a biomimetic sensor for the detection of sodium diclofenac from a glassy carbon electrode modified with copper(II) 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine complex and functionalized multi-walled carbon nanotubes (MWCNT-COOH). The proposed sensor was evaluated in batch system using 0.1 mol L-1 phosphate buffer solution at pH 7.5 as electrolyte support. A linear response was obtained in the range of 4.0 × 10-5 and 6.7 × 10-4 mol L-1, with the sensitivity of 6.1 × 10(5) (± 1.5 × 10(4)) µA L mol-1 and detection limit of 1.3 × 10-5 mol L-1 using square wave voltammetry. The selectivity was studied by the sensor response in the presence of other drugs. The sensor was applied to pharmaceutical formulations and also to biological serum samples by recovery studies. When coupled to a flow injection system (FIA), the best results were obtained by applying the potential of 0.5 V vs. Ag|AgCl|KCl sat, using an injected volume of the sample of 100 µL and a flow of 1.2 mL min-1. The linear response range in flow was between 5.0 × 10-5 and 5.0 × 10-3 mol L-1, with a sensitivity of 1.6 × 10(4) (± 3.0 × 10²) µA L mol-1and a relative standard deviation of 3.5%. (AU)

• FAPESP's process: 11/03008-7 - Development of electrochemistry sensors and methods of solid phase extraction based in biomimetic systems for analysis of environmental pollutants
• Grantee: Ademar Wong
• Support Opportunities: Scholarships in Brazil - Doctorate