An efficient 2-mercapto-5-phenylamino-1,3,4-thiadiazole functionalized magnetic graphene oxide nanocomposite for preconcentrative determination of mercury in water and seafood samples

In this work, an efficient 2-mercapto-5-phenylamino-1,3,4-thiadiazole (2-MPATD) modified magnetic graphene oxide was synthesized and utilized to preconcentrative determination of inorganic mercury (Hg(II) ions) in water and seafood samples. At first graphene oxide sheets were decorated with Fe3O4 NPs to obtain magnetic graphene oxide, and then magnetic graphene oxide sheets were coated with a silica layer. Afterwards, magnetic graphene oxide@SiO2 was functionalized by 2-MPATD (mGO@SiO2@2-MPATD nanocomposite). FT-IR, SEM, elemental analysis and vibrating sample magnetometry techniques were employed to characterize the nanosorbent. Experimental design was performed to monitor and find the parameters that affect the extraction performance. After sorption and elution steps, the concentration of Hg(II) was measured by employing cold vapor atomic absorption spectrometry. The highest extraction performance was achieved under the following conditions: sorption time (10.0 min), pH value (6.3), sorbent amount (16 mg); eluent (HNO3 solution; 1.25 mol L-1; 1.7 mL), and elution time (14.0 min). The obtained detection limit was 0.008 ng mL(-1). Finally, the method was utilized for rapid determination of mercury ions in various real samples, satisfactorily.