Development of a Disposable Aptasensor Using Carboxymethyl Cellulose and Hydroxyapatite Nanoparticles for Voltammetric Detection of Glyphosate

The development of monitoring tools for the detection of glyphosate 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 glyphosate. 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, glyphosate specific DNA aptamer that had G-quadruplex structure was immobilized at the surface of CMC/HaNP-PGEs. The specific interaction between DNA aptamer and glyphosate was performed at the electrode surface. Before/after each modification/immobilization/interaction step, anodic current value obtained by cyclic voltammetry measurements performed in 2.00 mM K-3[Fe(CN)(6)]/K-4[Fe(CN)(6)] (1:1) and 0.10 M KCl was recorded, and the changes at the average anodic current values were evaluated in terms of the optimization of experimental parameters. The limit of detection and limit of quantification values were calculated as 0.04 and 0.13 mu g ml(-1), respectively. The selectivity of the developed aptasensor was tested against 2,4-dichlorophenoxyacetic acid, glufosinate, and (aminomethyl) phosphonic acid. 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.