Efficient Hg(II) ionic probe development based on one-step synthesized diethyl thieno[2,3-b]thiophene-2,5-dicarboxylate (DETTDC2) onto glassy carbon electrode

Abstract

In this approach, diethyl thieno [2,3-b] thiophene-2,5-dicarboxylate-2 (DETTDC2) was prepared in one-pot synthesis by using pentan-2,4‑dione (P24D), carbon disulfide, and ethyl bromoacetate (EBA) precursors and finally the characterization was carried out systematically with proton-Nuclear Magnetic Resonance (HNMR), Impedance spectroscopy (EIS), Fourier-transform infrared spectroscopy (FTIR) and carbon hydrogen and nitrogen (CHN) analyzer. An ultra-thin sheet of DETTDC2 was retained on a glassy carbon electrode (GCE) with managing binder to evolve the expected working electrode of Hg(II) cationic sensors. The calibration plot was determined based on the current vs. amount of Hg(II) ion and the final calibration curve was appeared to be linear (r2: 0.9979) over the low to high range (LDR: 0.1 nM ∼ 0.01 M). The sensor performance in term of sensitivity (0.74367 µA µM−1 cm−2) was predicted from the slope of calibration plot. It was also measured the detection limit (DL: 12.80 ± 0.64 pM) of the sensor at signal to noise ratio of 3. This sensor was applied to sensitive detection of Hg(II) ions in phosphate buffer condition. Therefore, this novel electrochemical approach is the suitable method for designing the toxic heavy-metal detection to safe-guard the public health and environment remediation.