Simple laccase-based biosensor for formetanate hydrochloride quantification in fruits

• Type: Article in International Scientific Journal
• Date: 2014

Authors

Francisco Wirley P Paulino Ribeiro (Author) Other; Maria Fatima Barroso (Author) Other; Simone Morais (Author) Other; Subramanian Viswanathan (Author) Other; Pedro de Lima Neto (Author) Other; Adriana N Correia (Author) Other; Maria Beatriz P P Prior Pinto Oliveira (Author) FFUP; Cristina Delerue Matos (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: BIOELECTROCHEMISTRY

Vol. 95

Pages: 7-14

ISSN: 1567-5394

Indexing

ISI Web of Knowledge - 24 Citations

Scopus - 36 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-008-FN0

DOI: 10.1016/j.bioelechem.2013.09.005

Abstract (EN): This work describes the development of an electrochemical enzymatic biosensor for quantification of the pesticide formetanate hydrochloride (FMT). It is based on a gold electrode modified with electrodeposited gold nanoparticles and laccase. The principle behind its development relies on FMT's capacity to inhibit the laccase catalytic reaction that occurs in the presence of phenolic substrates. The optimum values for the relevant experimental variables such as gold nanoparticles electrochemical deposition (at -0.2 V for 100 s), laccase immobilization (via glutaraldehyde cross-linking), laccase concentration (12.4 mg/mL), substrate selection and concentration (5.83 x 10(-5) M of aminophenol), pH (5.0), buffer (Britton-Robinson), and square-wave voltammetric parameters were determined. The developed biosensor was successfully applied to FMT determination in mango and grapes. The attained limit of detection was 9.5 x 10(-8) +/- 9.5 x 10(-10) M (0.02 +/- 2.6 x 10(-4) mg/kg on a fresh fruit weight basis). Recoveries for the five tested spiking levels ranged from 95.5 +/- 2.9 (grapes) to 108.6 +/- 2.5% (mango). The results indicated that the proposed device presents suitable characteristics in terms of sensitivity (20.58 +/- 0.49 A/mu M), linearity (9.43 x 10(-7) to 1.13 x 10(-5) M), accuracy, repeatability (RSD of 1.4%), reproducibility (RSD of 1.8%) and stability (19 days) for testing of compliance with established maximum residue limits of FMT in fruits and vegetables.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8