LAUSR

The development of monitoring tools for the detection of glyphosate (GLY) is an attractive topic since its consumption is one of the debated worldwide issue. Herein, a bionanocomposite modified disposable electrochemical biosensor platform was developed for sensitive and selective detection of GLY. For this purpose, carboxymethyl cellulose (CMC) and hydroxyapatite nanoparticles (HaNP) were modified at the surface of disposable pencil graphite electrodes (PGEs). After the fabrication of CMC/HaNP-PGEs, GLY specific DNA aptamer (DNA APT) that had G-quadruplex structure was immobilized at the surface of CMC/HaNP-PGEs. The specific interaction between DNA APT and GLY was performed at the electrode surface. Before/after each modification/immobilization/interaction step, anodic current (Ia) value obtained by cyclic voltammetry (CV) measurements performed in 2.00 mM K3[Fe(CN)6]/K4[Fe(CN)6] (1:1) and 0.10 M KCl was recorded, and the changes at the average Ia values were evaluated in terms of the optimization of experimental parameters. The LOD and LOQ values were calculated as 0.04 and 0.13 µg/mL, respectively. The selectivity of the developed aptasensor was tested against 2,4-dichlorophenoxyacetic acid (2,4-D), glufosinate (GFS), and (aminomethyl) phosphonic acid (AMPA). The applicability of the aptasensor was shown using water samples. This novel aptasensor platform is a prototype for future hand-held devices developed for GLY monitoring.