Electrochemical Sensor Based on Beeswax and Carbon Black Thin Biofilms for Determination of Paraquat in Apis mellifera Honey

The development of new materials for electrochemical sensors has been received attention due to the search for sustainability. However, the use of in natura materials from vegetable and animal origin is still little explored for this purpose. Therefore, this work aims to use beeswax as biofilm, as an environmentally friendly and sustainable platform for incorporating carbon black nanoparticles. The electrode was prepared by a simple dispersion of beeswax and carbon black on the surface of the glassy carbon electrode. The proposed modified electrode was used to determine the herbicide paraquat (PQ) in 3 different samples of Apis mellifera honey. The presence of carbon black decreases the electrical resistance when compared with the bare electrode. The beeswax-carbon black film considerably increased the sensitivity of the PQ determination measures at a concentration range between 5.0 × 10−7 and 7.5 × 10−6 mol L−1. Samples with PQ contents between 7.5 × 10−7 and 7.5 × 10−6 mol L−1 presented recovery values from 97.2 to 114%. Also, the proposed sensor showed good repeatability and reproducibility for successive measurements. This suggests the use of the proposed electrode is feasible as an alternative strategy in the monitoring of herbicides in honey samples.