A square-wave anodic stripping voltammetric method for determining carbendazim in pineapple and orange juices without sample pre-treatment

Abstract

Carbendazim is a fungicide used for pest control in fruit crops. However, carbendazim is dangerous to human health and the environment, requiring monitoring by appropriate analytical methods. For this, a square-wave anodic stripping voltammetric method was developed for the first time for determining carbendazim in orange and pineapple juices. As a sensor, the proposed method uses a carbon paste electrode modified with cobalt phthalocyanine. The optimized voltammetric parameters were: rest time = 5 s, pulse amplitude = 30 mV, potential increment = 1.0 mV, frequency = 20 s−1, potential window ranging from + 0.6 to + 1.1 V, peak potential (+0.90 V) and deposition time = 45 s. The method presented a linear response (r2 = 0.994, n = 8, limits of detection = 0.57 nmol L−1) from 49.7 to 384.6 nmol L−1 carbendazim, good reproducibility (relative standard deviation = 2.4 %) and accuracy (recovery rates = 93.3–107.9 %). The proposed method is superior to other methods reported in the literature because the preparation of the sensor is faster, as well as being simple, sensitive, selective, low-cost, high-frequency analysis, and eco-friendly as it does not use any sample pre-treatment (sonication, centrifugation, filtration, pre-concentration, dilution and/or extraction with organic solvents).