Application of three-dimensional graphene hydrogels for removal of ofloxacin from aqueous solutions

Abstract

Antibiotics widely use around the world. There is an increasing demand for the removal of antibiotics from water due to their toxicity to living beings and the adsorption process regarded as a promising method for the removal of the antibiotic. Graphene hydrogel showed an adequate adsorption capacity for antibiotics via combined adsorption interaction mechanisms (e.g., π-π interaction, hydrogen bonding, and hydrophobic interaction). In this study, a one-step hydrothermal reduction method applied for the preparation of 3D porous graphene hydrogel adsorbents. The characteristic properties of synthesized graphene hydrogels were obtained using scanning electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller. Graphene hydrogels used for removing ofloxacin as widespread fluoroquinolone antibiotic drugs from aqueous solutions. Residual ofloxacin concentration was achieved using a low-cost and straightforward smartphone fluorimeter set–up. This set-up can quantify and compare fluorescent intensity in several samples simultaneously, which is a significant advantage. These results demonstrate that graphene hydrogel is a promising adsorbent for the removal of ofloxacin pollutants from aqueous solutions. Also, image processing smartphone application is the right candidate for inexpensive, accessible, and fast monitoring of ofloxacin pollutants.