Development of a novel hollow fiber-pencil graphite modified electrochemical sensor for the ultra-trace analysis of glyphosate

This study introduced an electrochemical sensor, based on pencil graphite electrode modified by hollow fiber (HF) pregnant by multi-walled carbon nanotube (MWCNTS)-ionic liquid (IL) composite and copper oxide nanoparticle (CuO) for extraction and in-situ determination of glyphosate (GPS) in real samples using differential pulse voltammetry (DPV). The electrode response is based on GPS oxidation. Different factors influencing the extraction and preconcentration, such as pH, extraction time, and stirring rate, were examined and the optimal extraction conditions were applied for in-situ monitoring of GPS. The relationship between the peak current and the concentration was linear over the range of 5 nM to 1.1 mu M (R-2=0.9988) with a limit of detection of 1.3 nM. The selectivity studied showed that the sensor can be utilized for detection of GPS in the presence of compounds with similar structure or herbicides, fungicide, pesticide, and insecticide that can be used simultaneously. The applicability of the developed technique was checked by real samples analyzing and its performance was compared with the results of a standard method.