A disposable chronocoulometric sensor for heavy metal ions using a diaminoterthiophene-modified electrode doped with graphene oxide.

摘要: The rapid simultaneous determination of cadmium, lead, copper, and mercury ions is performed by employing a disposable sensor modified with graphene oxide (GO) doped diaminoterthiophene (GO/DTT) for chronocoulometry (CC). performances CC without pre-deposition in two opposite potential step directions were compared square wave anodic stripping voltammetry (SWASV) under various conditions. surface the GO/DTT screen print carbon electrode (SPCE) was characterized SEM, EDXS, electrochemical impedance spectroscopy (EIS). Experimental variables that affect response signal such as pH, deposition time, type supporting electrolyte, concentration DTT, content ratio GO to Nafion optimized. Interference effects due other heavy metal also investigated. dynamic ranges SWASV between 1 ng mL(-1) 2.5 μg mL(-1) 10 μg mL(-1), respectively. detection limits Cd(2+), Pb(2+), Cu(2+), Hg(2+) 1.9 ± 0.4 ng mL(-1), 2.8 ± 0.6 ng mL(-1), 0.8 ± 0.2 ng mL(-1), 2.6 ± 0.9 ng mL(-1) method; 2.6 ± 0.2 ng mL(-1), 0.5 ± 0.1 ng mL(-1), 1.8 ± 0.3 ng mL(-1), 3.2 ± 0.3 ng mL(-1) 7.1 ± 0.9, 1.9 ± 0.3, 0.4 ± 0.1, 0.7 ± 0.1 ng mL(-1) SWASV. reliability method point-of-analysis evaluated analyzing urine standard reference material some water samples.