Disposable electrochemical sensor based on shellac and graphite for sulfamethoxazole detection

Author(s)

Henrique, Julia Melo ^[1] ; Camargo, Jessica Rocha ^[1] ; de Oliveira, Geiser Gabriel ^[2] ; Stefano, Jessica Santos ^[1] ; Janegitz, Bruno Campos ^[1]

Affiliation

^[1] Univ Fed Sao Carlos, Dept Nat Sci Math & Educ, BR-13600970 Araras, SP - Brazil

^[2] Fed Univ Tocantins, BR-77402970 Gurupi, Tocantins - Brazil

• Document type: Journal article
• Source: Microchemical Journal; v. 170, NOV 2021.
• Web of Science Citations: 0

Abstract

The growth in the demand for mass analysis, in a fast and safe way, with good reliability and low cost has aroused great scientific interest in the search for new devices that prioritize precision and time. In this sense, this work presents a simple, disposable, and easy-to-use electrochemical sensor, developed on a waterproof paper substrate with a conductive ink based on shellac, a resin of natural origin, and graphite. The conductive ink was obtained through a simple mixture of its components and deposited on the paper substrate, being ready to use after a drying period. The new sensor was employed for the electrochemical detection of sulfamethoxazole (SMX), an antibiotic belonging to the class of sulfonamides, which presents great importance due to its direct impact on the flow of the food chain and is, therefore, commonly found as a metabolic residue in environmental and food samples. Using the differential pulse voltammetry technique, a linear range of 5.0 mu mol L-1 -100 mu mol L-1 and a limit of detection of 0.4 mu mol L-1 were obtained. The electrochemical sensor was also employed for the analysis of SMX in water and milk samples, and recovery values between 91 and 110% were obtained, proving that the development and application of the new conductive ink proposed for the fabrication of disposable devices provided an efficient electrochemical detection of SMX in the applied samples. (AU)

• FAPESP's process: 19/23177-0 - Development of disposable devices with conductive inks and low cost substrates for the biosensing of hormonal dysfunctions and detection of Malaria
• Grantee: Jéssica Rocha Camargo
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 17/21097-3 - Bee-agriculture interactions: perspectives to sustainable use
• Grantee: Osmar Malaspina
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 20/04189-4 - Disposable sensors with conductive ink based on graphite and shellac on waterproof paper for detection of sulfamethoxazole
• Grantee: Julia Melo Henrique
• Support Opportunities: Scholarships in Brazil - Scientific Initiation