Highly efficient determination of malachite green in aquatic product using Tb-organic framework as sorbent

Environmental problems and food safety are very important public concern in recent years. Malachite green which is used as an antibacterial agent in aquaculture is a carcinogenic compound and causes the health risk. In this study, a terbium-metal–organic framework (Tb-MOF) was applied as a solid phase for extraction and spectrophotometric determination of malachite green (MG) residue in the aquatic product. Tb-MOF was synthesized by hydrothermal method and characterized. Several experimental parameters such as pH of the sample, sorption time, sorbent dosage were considered to investigate the synthesized Tb-MOF performance. The adsorption capacity of the Tb-MOF was studied based on the Langmuir isotherm and the maximum sorption capacity was obtained 480 mg g−1. Under the optimum conditions, the solid phase extraction procedure was performed in 5 min by methanol as eluent and the limits of detection calculated as 1.66 ng mL−1. The fast and simple proposed method was successfully applied to the determination of MG in water and fish samples with the spiked recoveries ranging from 95.6 to 104.3%.