Procedure 7 Determination of lead and cadmium in tap water and soils by stripping analysis using mercury-free graphite–epoxy composite electrodes

2007 ◽  
pp. e47-e52 ◽  
Author(s):  
Arben Merkoçi ◽  
Ulku Anik-Kirkoz ◽  
Salvador Alegret
Keyword(s):  
Epoxy Composite ◽  
Tap Water ◽  
Composite Electrodes ◽  
Stripping Analysis ◽  
Lead And Cadmium

scholarly journals Electrodeposition of 4-Benzenesulfonic Acid onto a Graphite-Epoxy Composite Electrode for the Enhanced Voltammetric Determination of Caffeine in Beverages

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Leonardo de A. Furtado ◽  
Mariana C. de O. Gonçalves ◽  
Carlos V. M. Inocêncio ◽  
Edilson M. Pinto ◽  
Daniela de L. Martins ◽  
...  
Keyword(s):  
Composite Electrode ◽  
Epoxy Composite ◽  
Reference Method ◽  
Diazonium Salts ◽  
Composite Electrodes ◽  
Wave Voltammetry ◽  
Linear Behaviour ◽  
Chromatographic Procedure ◽  
Kinetics Of

Caffeine is widely present in food and drinks, such as teas and coffees, being also part of some currently commercialized medicines, but despite its enhancement on several functions of human body, its exceeding use can promote many health problems. In order to develop new fast approaches for the caffeine sensing, graphite-epoxy composite electrodes (GECE) were used as substrate, being modified by different diazonium salts, synthetized as their tetraflouroborate salts. An analytical method for caffeine quantification was developed, using sware wave voltammetry (SWV) in Britton–Robinson buffer pH 2.0. Detection limits for bare electrode and 4-benzenesulfonic modified electrode were observed circa 145 µmol·L−1 and 1.3 µmol·L−1, respectively. The results have shown that the modification shifts the oxidation peaks to lower potential. Kinetics of the reaction limited by diffusion was more expressive when caffeine was added to the solution, resulting in decreases of impedance, characterized by lower Rct. All results for caffeine determination were compared to a reference chromatographic procedure (HPLC), showing no statistical difference. Analytical parameters for validation were suitably determined according to local legislation, leading to a linear behaviour from 5 to 150 µmol·L−1; precision of 4.09% was evaluated based on the RDC 166/17, and accuracy was evaluated in comparison with the reference method, with recovery of 98.37 ± 2.58%.

scholarly journals Determination of lead, cadmium and zinc applying the stripping analysis on biomass of natural grasslands

2011 ◽  
Vol 27 (2) ◽  
pp. 251-257
Author(s):  
Lj.M. Babincev ◽  
Lj.V. Rajakovic ◽  
M.V. Budimir ◽  
I. Sredovic
Keyword(s):  
Metal Extraction ◽  
Stripping Analysis ◽  
Real Samples ◽  
Metal Determination ◽  
Potential Value ◽  
Lead And Cadmium ◽  
Natural Grasslands ◽  
Heavy Metal Determination ◽  
Natural Grassland

This study is focused on mechanisms of voltammperometric determination of lead, cadmium and zinc in the natural grassland biomass in territory of northern Kosovo, applying the Stripping analysis. Two types of determinations have been researched: individual and simultaneous research of all three metals. The preliminary researches had been conducted prior determinations on real samples defining the determination conditions: extraction potential, value of analyzed pH solution, metal extraction time, time for creating of working electrode, as well as solution mixing velocity. It was found that, with accuracy of ?2%, determinations were done for 22-900 ?g dm-3 of lead, 16-960 ?g dm-3 of cadmium and 18-750 ?g dm-3 of zinc. The simultaneous metal determinations had less accurate results for lead and cadmium, whereas they ranged within accuracy limits for zinc. Heavy metal determination in biomass indicated existence of lead, cadmium and zinc in natural grasslands in northern parts of Kosovo and Metohija.

Direct Determination of Cadmium and Lead in Whole Blood by Potentiometric Stripping Analysis

1992 ◽  
Vol 38 (10) ◽  
pp. 1995-2001 ◽  
Author(s):  
P Ostapczuk
Keyword(s):  
Detection Limit ◽  
Blood Sample ◽  
Whole Blood ◽  
Deposition Time ◽  
Supporting Electrolyte ◽  
Direct Determination ◽  
Stripping Analysis ◽  
Lead And Cadmium ◽  
Potentiometric Stripping Analysis

Abstract The commercially available equipment for potentiometric stripping analysis (PSA) was tested for routine lead and cadmium determination in whole-blood samples. In contrast to anodic stripping voltammetry, PSA is not subject to background interferences from organic electroactive constituents in the sample or to the presence of dissolved oxygen (i.e., oxygen removal is not necessary). To determine lead and cadmium by PSA, it is sufficient to dilute the blood sample with an appropriate supporting electrolyte (0.5 mol/L HCl). The detection limit changes with deposition time and volume of blood sample used. For 1 mL of blood and a 1-min deposition time, the detection limit is 1 microgram/L for both elements. If the deposition time increases to 10 min, cadmium can be determined at its normal concentration in blood (the detection limit is improved to < 0.1 microgram/L). Procedures for routine determination of lead and cadmium in whole blood are presented.

scholarly journals Spectrometric Determination of Lead, Cadmium, Arsenic, Copper and Iron in Drinking Water Samples Across Kogi State, Nigeria.

2021 ◽  
Vol 46 (1) ◽  
Author(s):  
D. M. Ocheni
Keyword(s):  
Water Samples ◽  
Tap Water ◽  
Absorption Spectrometry ◽  
High Concentration ◽  
Mean Values ◽  
Lead And Cadmium ◽  
Arsenic Copper ◽  
Drinking Water Samples ◽  
Determination Of Copper

The aim of the study was to determine the levels of lead, cadmium, arsenic copper and iron in 25 water samples collected from across Kogi State. Atomic absorption spectrometry was used in the determination of copper, iron, lead and cadmium while UV-visible spectrophotometer was employed in the determination of arsenic, based on the formation of Molybdoarsenate. The ranges of mean values obtained for the heavy metals are: Arsenic (0.0014to 0.0252 mg/L), Copper (0.0013to 0.0095 mg/L), Lead (0.0001to 0.024 mg/L), Cadmium (0.003 to 0.072 mg/L) and Iron (0.0068 to 0.1242 mg/L). The results revealed that the River, Stream and Tap water sampled were contaminated with Arsenic (As), whereas, the levels of Fe, Cu and Pb were within the recommended limit set by WHO and NAFDAC. Though the level of cadmium (Cd) falls within acceptable limit in some of water samples, its high concentration in Isanlu should attract the attention of the authority in this area in curbing the growing threat.

Determination of musks and other fragrance compounds at ng/L levels using CLSA (closed loop stripping analysis) and GC/MS detection

2004 ◽  
Vol 50 (5) ◽  
pp. 119-123 ◽  
Author(s):  
D. Mitjans ◽  
F. Ventura
Keyword(s):  
Closed Loop ◽  
Matrix Effects ◽  
Limit Of Detection ◽  
Tap Water ◽  
Quality Parameters ◽  
Stripping Analysis ◽  
Polycyclic Musks ◽  
Relative Standard ◽  
High Resolution Gas Chromatography

Closed loop stripping analysis (CLSA), a suitable tool for the determination of volatile and semivolatile compounds at low trace levels (ng/l), has been used to determine and quantify seven selected musks and two fragrances (Acetyl cedrene and Amberonne). The obtained extracts are analyzed by high resolution gas chromatography coupled to mass spectrometry (GC/MS) operating in the SIM mode. Quality parameters such as limit of detection; matrix effects; precision expressed as repeatability and reproducibility relative standard deviations of the method and an estimation of the uncertainty have been evaluated. The method has been applied to the analysis of wastewater effluents, surface water and tap water from different places in Europe. All samples contained differents musks at ng/l levels with the polycyclic musks Galaxolide and Tonalide and both fragrances, Amberonne and Acetyl cedrene, being the most abundant. These results suggest the importance of studying and controlling the presence of these ubiquitous environmental compounds in water systems.

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