In this project, a nanosorbent was prepared using graphene oxide nanosheets modifed with a specifc mercury aptamer to detect very low mercury concentrations in aqueous solutions. The properties of the prepared nanosheets as adsorbents in the adsorption of mercury cations by microextraction in a packed syringe and analysis with a spectrophotometer were evaluated. Scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray energy difraction were used to characterize the nanosheets obtained. The optimization conditions afecting the extraction and determination of mercury by spectrophotometry such as the infuence of the pH of the aqueous solution, the number of sample loading times, the number of desorption times, the contact time of the analyte with the adsorbent, the amount of adsorbent and the volume of wash solvent were investigated. Under optimization conditions, the calibration curve of the method was linear between 20 and 800 μg L−1, and the detection limit of the method was 2.2 μg L−1. Mercury analysis in real samples such as Gavoshan dam water, Gamasiab river water and Bashir Taq Bostan spring water was also investigated to evaluate the method.
