• Journal of Oral Medicine and Pain
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• v.32 no.4
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• pp.347-355
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• 2007

The aim of this study was to evaluate the differences of salivary lead (Pb) and cadmium (Cd) concentrations, using ASV analysis, after various pre-treatment procedures. 10 unstimulated whole saliva samples of non-exposed subjects to Pb and Cd were collected. Each sample was divided into 6 aliquots and centrifugation was performed in only 3 aliquots. After centrifugation, 3 different types of pre-treatment procedures were carried out. Also, these pre-treatment procedures were carried out for another 3 aliquots, without centrifugation. Pre-treated aliquots were analyzed electrochemically, by ASV. The results are as follows: 1. Mean concentration of Pb in saliva after centrifugation was significantly higher than that of non-centrifugation. 2. In the detection sensitivity of Pb in saliva, those of simple dilution technique by HCl and acid digestion technique by nitric acid were significantly higher than that of simple dilution technique by electrolyte. 3. Mean concentration of Cd in saliva after centrifugation was significantly higher than that of non-centrifugation. 4. In the detection sensitivity of Cd in saliva, those of simple dilution technique by HCl and acid digestion technique by nitric acid were higher than that of simple dilution technique by electrolyte. But, there were no significant differences between them.

• Journal of Electrochemical Science and Technology
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• v.7 no.3
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• pp.241-244
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• 2016

Anodic stripping voltammetry (ASV) is successfully applied in mM level detection of mercury ion in an electroplating bath which is currently used in preparing a cathodic electrolyzer. Glassy carbon electrode is used for the detection and the optimum condition obtained is 10 s deposition at −1.4 V vs. Ag/AgCl and stripping by scanning from −1.4 to +0.4 V vs Ag/AgCl at 50 mV/s. By applying the method, the mercury ion concentration in the electroplating bath could be successfully monitored during the plating.

• Bulletin of the Korean Chemical Society
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• v.31 no.11
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• pp.3077-3083
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• 2010

The electrochemical detection of As(III) was investigated on a platinum-iron(III) nanoparticles modified multiwalled carbon nanotube on glassy carbon electrode(nanoPt-Fe(III)/MWCNT/GCE) in 0.1 M $H_2SO_4$. The nanoPt-Fe(III)/MWCNT/GCE was prepared via continuous potential cycling in the range from -0.8 to 0.7 V (vs. Ag/AgCl), in 0.1 M KCl solution containing 0.9 mM $K_2PtCl_6$ and 0.6 mM $FeCl_3$. The Pt nanoparticles and iron oxide were co-electrodeposited into the MWCNT-Nafion composite film on GCE. The resulting electrode was examined by cyclic voltammetry (CV), scanning electron microscopy (SEM), and anodic stripping voltammetry (ASV). For the detection of As(III), the nanoPt-Fe(III)/MWCNT/GCE showed low detection limit of 10 nM (0.75 ppb) and high sensitivity of $4.76\;{\mu}A{\mu}M^{-1}$, while the World Health Organization's guideline value of arsenic for drinking water is 10 ppb. It is worth to note that the electrode presents no interference from copper ion, which is the most serious interfering species in arsenic detection.

• Journal of Biosystems Engineering
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• v.34 no.5
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• pp.377-381
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• 2009

Excessive presence of heavy metals in environment may contaminate plants and fruits grown in that area. Rapid on-site monitoring of heavy metals can provide useful information to efficiently characterize heavy metal-contaminated sites and minimize the exposure of the contaminated food crops to humans. This study reports on the evaluation of a bismuth-coated glassy carbon electrode for simultaneous determination of cadmium (Cd) and lead (Pb) in a NIST-SRM 1568a rice flour by anodic stripping voltammetry (ASV). The use of a supporting electrolyte 0.1 M $HNO_3$ at a dilution ratio (sample pretreated with acid digestion in a microwave oven: supporting electrolyte) of 1:1 provided well-defined, sharp and separate peaks for Cd and Pb ions, thereby resulting in strongly linear relationships between Cd and Pb concentrations and peak currents measured with the electrode ($R^2\;=\;0.97$, 0.99 for Cd and Pb, respectively). The validation test results for spiked standard solutions with different concentrations of Cd and Pb gave acceptable predictability for both spiked Cd and Pb ions with mean prediction errors of 6 to 30%. However, the applicability of the electrode to the real rice flour sample was limited by the fact that Cd concentrations spiked in the rice flour sample were overly estimated with relatively high variations even though Pb ion could be quantitatively measured with the electrode.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.404-408
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• 2003

In this study, we examined the influences of pH and total concentration on the speciation of heavy metals (Cd, Cu, Zn) in acid mine drainage. Their labile concentrations were analyzed by Anodic Stripping Voltammetry (ASV) at both natural pH and adjusted pHs (from 2 to 8). We obtained regression equations for predicting labile concentrations as a function of the water pH and contamination level (total dissolved metal concentration). Our data show that labile Cu depends on both the total concentration and pH, while labile Cd and Zn concentrations are controlled mainly by their total concentration rather than pH. Therefore, the pH variation of AMD may significantly change the toxicity and bioavailability especially of Cu, owing to its speciation change.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1100-1105
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• 2020

We investigated the driving force and the required charges for spontaneous reduction of metal nanoparticles (NPs) on a scotch tape induced by mechanochemical activation. The charges were analyzed based on anodic stripping voltammetry (ASV) of silver, which is proportional to the number of charge identities on the tape. The results supported that the driving force is mechanochemical radicals rather than ions in the light of the high charge density on the tape.

• Journal of Biosystems Engineering
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• v.33 no.6
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• pp.404-409
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• 2008

Excessive presence of heavy metals in environment affects plants and fruits grown in the contaminated area. Rapid on-site monitoring of heavy metals can provide useful information for efficiently characterizing heavy metal-contaminated sites and for minimizing the exposure of the contaminated food crops to humans. This study reports on the evaluation of gold and glassy carbon (GC) electrodes with mercury or bismuth as a coating material for simultaneous determination of cadmium (Cd) and lead (Pb) in 0.1 M $HNO_3$ solution by anodic stripping voltammetry (ASV). The use of a square-wave voltammetric potential between a working electrode and a reference electrode caused Cd and Pb ions deposited on the electrode surface to be oxidized, thereby generating electric currents at different potentials. The mercury-coated gold electrode was not sensitive enough to detect the usable range of Cd concentrations (1 to 100 ppb). The GC electrodes with mercury or bismuth displayed well-defined, sharp and separate current peaks for Cd and Pb ions when the square-wave voltammetric potentials were applied. The peak currents measured with both mercury- and bismuth- coated GC electrodes were linearly proportional to Cd and Pb concentrations in the range of 1 to 200 ppb in 0.1 M $HNO_3$ with strong linear relationships between concentration and peak current ($R^2$ > 0.95), indicating that both of Cd and Pb ions could be quantitatively measured.

• Journal of the Korean Chemical Society
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• v.37 no.5
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• pp.477-482
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• 1993

The determination of trace level mercury in bio-materials has been investigated by the square wave anodic stripping voltammetry (ASV)-technique at glassy carbon electrode. Prior to analysis, the bio-materials were digested with HNO3/H2SO4 mixture and KMnO4 was added to complete the oxidation. The detection limit of the mercury varied greatly with deposition time, deposition potential, pH and stirring rate. When deposition is carried out for 240 sec with 400 rpm stirring at -1.0 volts vs. Ag/AgCl, the detection limit was below $0.5\;ppb\;(2.5{\times}10^{-9} M)$. The method is recommended for trace level mercury analysis of biomaterials because this procedure is time saving and has higher sensitivity.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.09a
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• pp.291-295
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• 2002

We measured the concentrations of heavy metals and VOCs in groundwaters (N=38) in Seoul. The comparison of our data with U.S. Environmental Protection Agency's Maximum Contaminant Levels for Drinking Water and with the Korean Drinking Water Standards shows that most of the metals except for Fe and Mn do not exceed the levels. However, the concentrations of most heavy metals (esp., Zn, Cu, Cr, Ni) tend to increase in residential and industrialized areas. The examination of the metal speciation using Anodic Stripping Voltammetry (ASV) and TOC analyzer Indicates that large amounts of Zn occur as labile metal fraction, whereas Cu occurs as non- labile forms at many sites, possibly due to its tendency to be adsorbed onto inorganic colloidal particles to form electroinactive species in groundwater. The most frequently existed VOCs in Seoul groundwaters are trichloroethylene and tetrachloroethylene, especially in agricultural, industrial, and high traffic areas.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.2
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• pp.137-142
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• 2011

This study was conducted to establish the optimal electrolyte and bismuth concentrations using bismuth film electrode in laboratory and to confirm the possibilities of using this operational condition for heavy metals monitoring in field. In lab test, heavy metal measurement was not accurate more than 600 ppb when heavy metal (Pb, Cd, Zn) range 100~1,000 ppb was measured with bismuth 2,000 ppb. So, bismuth and heavy metal was reacted about 1:1 with ASV method. In electrolyte test, 0.1 M acetate buffer (pH 4.5), 0.1 M chloroacetate buffer (pH 2.0), 0.1 M HCl (pH 2.0), 0.1 M $HNO_3$ (pH 2.0) was tested. As a results, 0.1 M acetate buffer was most suitable in ASV measurement with bismuth film electrode. In field application, Pb, Cd and Zn was measured respectively 36~45 ppb, 84~91 ppb, 90~98 ppb when heavy metal (Pb, Cd, Zn) 100 ppb was spiked in field sample. These results were identified of matrix effect in field sample, So relationship between heavy metal measurement and matrix effects will be studied.