Simultaneous quantification of Cd(II) and Pb(II) in surface marine sediments using Ag–Hg and Ag–Bi nanoalloys glassy carbon modified electrodes

Abstract

The evaluation of glassy carbon (GC) electrodes modified with a Nafion (Nf) film and doped with nanoalloys (Nys) deposits of Ag–Hg and Ag–Bi and their application to determination of Cd (II) and Pb(II) in marine sediments, is described. Deposited Ag–Hg and AgBi Nys have a size of approximately ~80 nm dispersed and embedded inside the booths of the Nf net, while other of them remained on Nf net surface. For the AgBiNysNf-GC electrode, a detection limit (DL), 3 s criterion, slightly higher than for the AgHgNysNf-GC modified electrode was obtained. Accuracy of measurements was asserted by comparison with quantification of Cd and Pb in three sets of marine sediments samples previously analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The values of the standard deviation and the coefficients of variation are very low, and also comparable between the different determinations.

Simultaneous DPAdSV for Heavy Metals Determination in the Seawater of a Former Bauxite Mining Area

“…However, above -0.3 V, the resulting Ip decreased, due to the perfect deposition on the electrode surface, and stripping occurence. Therefore, when E went towards a negative value, no more analytes were deposited (3,31). Measurement data show that the optimum Edep was at -0.3 V, which was used for further determinations.…”

“…Despite Pb, Cd and Zn being heavy elements that are still needed by the environment, they are non-essential metals that are considered as one of the major industrial wastewater contaminants, even at trace concentrations (2). Therefore, developing selective, sensitive, fast, simple and accurate methods is required for the determination of these metals in the environment (3)(4)(5). Methods for the analysis of metal ions include ICP-AES (6), AAS (7), ICP-MS (8), ICP-OES (9), ISEs (10), TXRF (11) and PXRF (12).…”

“…Therefore, there is the need of an alternative method that can overcome the limitations of those techniques. DPAdSV was chosen, because it has many advantages, such as not being affected by the seawater high salinity, having high sensitivity, low LOD, selectiveness and easy sample preparation, and being more fast and precise than of other instrument techniques (3,15,16). In addition, the DPAdSV preconcentration stage is shorter than that of other methods, which is generally less than one minute (17)(18)(19).…”

Mercury (II) sensor by forming Hg/Ag amalgam based on silver nanoparticles modified screen-printed carbon electrode

“…It has been reported that adsorption of Hg to silver [33] or gold [34] particles surfaces shifted the surface plasmon resonance spectroscopy of the nanoparticles to shorter wavelengths, indicating the interaction of between the atoms of Hg 0 and Ag 0 . In the past decades, silver amalgam electrodes are intensively sought to substitute the convenient mercury electrode material for electrochemical detections of various targets [35][36][37]. SEM combining with EDX was performed to con rm the formation of Hg/Ag amalgam (Fig.…”

Recent advances in the modification of electrodes for trace metal analysis: a review

“…A combination of two polymers (i.e., conductive polydopamine (PDA) doped PPy hydrogel) as modifiers of an SPCE for the determination of Pb 2+ has also been reported. 232 Biopolymers (mainly chitosan and different forms of cellulose) 35,37,61,69,[71][72][73]87,89,92,123,124,175,186,187,197,[200][201][202][203][204][205] (further discussed in section 7) and Nafion (a sulfonated tetrafluoroethylene-based fluoropolymer-copolymer) 24,62,108,113,149,154,155,179,200,[233][234][235][236][237][238][239][240][241] are by far most frequently used as polymeric components of the nanocomposites. Moreover, other conducting polymers such as polyaniline (PANI), 23,38,99,102,122,…”