Very sensitive electrochemical sensor for moniliformin detectionin maize samples

PAULO CÉSAR DÍAZ TORO; FERNANDO JAVIER ARÉVALO; FUMERO, M.V.; MARÍA ALICIA ZON; HÉCTOR FERNÁNDEZ

SENSORS AND ACTUATORS B-CHEMICAL

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2016 vol. 225 p. 384 - 390

0925-4005

A highly sensitive electrochemical sensor based on self-assembled monolayers (SAMs) of cysteamineon gold electrodes (Au-CA) in pH 4 citrate buffer solutions was developed to quantify the moniliformin(MON) mycotoxin by cyclic voltammetry in contaminated maize samples. Parameters of SAMs modifiedgold electrodes such as concentration of thiol, modification time and MON accumulation time wereadjusted to obtain the best performance of the sensor. The calibration curve was linear in the MONconcentration range from 1 × 10−9to 1 × 10−7mol L−1. A limit of detection of 8.3 × 10−10mol L−1(0.1 ppb)was obtained. The standard addition method was used to minimize matrix effects. The concentration ofMON determined with the electrochemical sensor was in very good agreement with results found by HPLCUV?vis. The sensor showed a good analytical performance with a relative standard deviation (RDS%) ofabout 3%.