Determination of Some Heavy Metal Ions with a Carbon Paste Electrode Modified by Poly(glycidylmethacrylate‐methylmethacrylate‐divinylbenzene) Microspheres Functionalized by 2‐Aminothiazole

Abstract

A carbon paste electrode modified with 2-aminothiazole functionalized poly(glycidylmethacrylate-methylmethacrylate-divinylbenzene) microspheres was used for trace determination of mercury, copper and lead ions. After the opencircuit accumulation of the heavy metal ions onto the electrode, the sensitive anodic stripping peaks were obtained by square wave anodic stripping voltammetry (SWASV)). Many parameters such as the composition of the paste, pH, preconcentration time, effective potential scan rate and stirring rate influence the response of the measurement. The procedures were optimized for most sensitive and reliable determinations of the desired species. For a 10-min preconcentration time in synthetic solutions at optimum instrumental and experimental conditions, the detection limit (LOD) was 12.3, 2.8 and 4.5 mg L À1 for mercury, copper and lead, respectively. The limits of detection may be enhanced by increasing the preconcentration time. For example, LOD of mercury and copper was 4.9 and 1.0 mg L À1for fifteen minutes preconcentration time. The sensitivity may also considered to be increased by using a more suitable electrode composition targeting the more conductive electrode with lesser amount of modified polymer for sub-mg L À1 levels of heavy metal ions. The optimized method was successfully applied to the determination of copper in tap water and waste water samples by means of standard addition procedure. The copper content found was comparable with the certified concentration of the waste water sample. The calibration plots for mercury and lead spiked real samples were also drawn.

Trace determination of cadmium in water using anodic stripping voltammetry at a carbon paste electrode modified with coconut shell powder

“…But, due to different issues related to its harmful effects and disposal, it is strongly recommended to replace mercury with another electrode material. Recently, modified carbon paste electrodes can be a better substitute of mercury-based electrodes due to its simplicity of preparation, the versatility of chemical modification, rapid renewal of the electrode surface, and sensitivity equivalent to that of mercury-based electrodes (Roa et al 2003;Sar et al 2008;Heitzmann et al 2005;Lu et al 2011;Li et al 2009a, b;Bagheri et al 2012). Thus, modified carbon paste electrodes (MCPEs) and related sensors using different types of modifiers (chemicals, enzymes, and extracts) have been developed (Chow and Gooding 2006;Heitzmann et al 2005;Ensafi et al 2010;Portaccio et al 2010).…”

Electrode Materials (Bulk Materials and Modification)

“…CPEs were modified with a wide range of chelating resins (i.e., containing N-and/or S-based functional groups) likely to bind metal ions prior to their electrochemical detection. [822][823][824][825][826] Molecularly imprinted polymers (i.e., macromolecular compounds formed in the presence of a molecule that is extracted afterwards, thus leaving complementary cavities behind, which can then be exploited to the selective accumulation of the original molecule) were also exploited for their selective recognition properties (e.g., towards pesticides, phenol derivatives or explosives [827][828][829] ). Several natural macromolecular compounds (humic substances, [830][831][832] lichens, 833,834 or keratin 835 ) were modifiers of CPEs 845 ).…”

Elastomer composite based on EPDM reinforced with polyaniline coated curauá fibers prepared by mechanical mixing

“…23 Calibration methods were applied to polymers to study some specific properties like: degree of crystallinity, 24 additive concentrations, 25 composition of processed polymer or blend, 19 moisture content, 26 status of reaction in a reactive extrusion, 27 presence of recycled polymers, 28 and quantification of heavy metals. 29 The presence of chemical groups in polymeric materials can be deduced using its vibrational spectra. 30 Band intensities have quantitative information about these chemical groups and a relationship between band intensities and concentration of the mixture components can be achieved using a calibration model.…”