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Novel polymer-modified electrodes for batch injection sensors and application to environmental analysis

Brett, Christopher M. A.; Fungaro, Denise A.; Morgado, José M.; Gil, M. Helena
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
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Various polymer coatings have been investigated for the protection of mercury thin-film electrodes in the square wave anodic stripping voltammetry of environmental samples using batch injection analysis, with injection of untreated samples of volume 50 [mu]l directly over the sensing electrode. Polymer coatings studied include those with controlled porosity, and cation-exchange polymers based on sulphonated polymers. Of the polymers tested, films of ca. 1 [mu]m thickness made from Nafion® mixed with 5% poly(vinyl sulphonic acid) were found to give the best results in tests with the model surfactants Triton-X-100 detergent, sodium dodecyl sulphate and protein standard. The validity of the approach is demonstrated by application to real samples.; http://www.sciencedirect.com/science/article/B6TGB-3WS69WY-1G/1/482035fd36bbbdaace32d2213fe93529

Electrochemical Impedance Characterization of Nafion-Coated Carbon Film Resistor Electrodes for Electroanalysis

Gouveia-Caridade, Carla; Brett, Christopher M. A.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica
ENG
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Carbon film disk electrodes with Nafion coatings have been characterized by electrochemical impedance spectroscopy (EIS) with a view to a better understanding of their advantages and limitations in electroanalysis, particularly in anodic stripping voltammetry of metal ions. After initial examination by cyclic voltammetry, spectra were recorded over the full potential range in acetate buffer solution at the bare electrodes, electrodes electrochemically pretreated in acid solution, and Nafion-coated pretreated electrodes in the presence and absence of dissolved oxygen. EIS equivalent circuit analysis clearly demonstrated the changes between these electrode assemblies. In order to simulate anodic stripping voltammetry conditions, spectra were also obtained in the presence of cadmium and lead ions in solution at Nafion-coated electrodes, both after metal ion deposition and following re-oxidation. Permanent changes to the structure of the Nafion film occurred, which has implications for use of these electrode assemblies in anodic stripping voltammetry at relatively high trace metal ion concentrations.; http://dx.doi.org/10.1002/elan.200403127

Characterization of Carbon Film Electrodes for Electroanalysis by Electrochemical Impedance

Filipe, Olga M. S.; Brett, Christopher M. A.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica
ENG
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The interfacial behavior of electrodes fabricated from carbon film resistors of 2 and 20 Omega in supporting electrolyte solutions of varying pH used in electroanalytical experiments has been characterized by electrochemical impedance spectroscopy with complementary cyclic voltammetric experiments. Equivalent circuits are proposed to fit the experimental data and the influence of electrode pretreatment has also been investigated.; http://dx.doi.org/10.1002/elan.200402911

Eletrodo compósito à base de grafite-araldite®: aplicações didáticas; Graphite-araldite® composite electrode: didactic applications

CALIXTO, Carolina Maria Fioramonti; CERVINI, Priscila; CAVALHEIRO, Éder Tadeu Gomes
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
POR
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A composite electrode prepared by mixing a commercial epoxy resin Araldite® and graphite powder is proposed to be used in didactic experiments. The electrode is prepared by the students and applied in simple experiments to demonstrate the effect of the composite composition on the conductivity and the voltammetric response of the resulting electrode, as well as the response in relation to the scan rate dependence on mass transport. The possibility of using the composite electrode in quantitative analysis is also demonstrated.

Aplicação do ultra-som em sistemas eletroquímicos: considerações teóricas e experimentais; Ultrasound applications in electrochemical systems: theoretical and experimental aspects

GARBELLINI, Gustavo S.; SALAZAR-BANDA, Giancarlo R.; AVACA, Luis A.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica
POR
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The aim of this review is to present and discuss the applications of ultrasound in electrochemical systems such as in sonoelectroanalysis and sonoelectrolysis for the electrochemical combustion of organic compounds. Initially, theoretical and experimental aspects are discussed, particularly those related to the enhancement of mass transport and the surface cleaning effects. Some results are included to illustrate alternative geometries for the experimental measurements and the working electrodes used in these systems. In the sequence, the available publications are presented and discussed to demonstrate that ultrasound combined with electrochemical techniques is a powerful set-up for the detection of analytes such as metals and/or organic compounds in hostile media and for the effective destruction of toxic organic substances. At the end, a table summarizes the results already published in the literature.; CNPq; FAPESP

Bismuth Modified Gold Microelectrode for Pb(II) Determination in Wine Using Alkaline Medium

SALLES, Maiara Oliveira; SOUZA, Ana Paula Ruas de; NAOZUKA, Juliana; OLIVEIRA, Pedro Vitoriano de; BERTOTTI, Mauro
Fonte: WILEY-V C H VERLAG GMBH Publicador: WILEY-V C H VERLAG GMBH
Tipo: Artigo de Revista Científica
ENG
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Electrodeposition of bismuth on gold microelectrodes for determination of Pb(II) by square wave anodic stripping voltammetry (SWASV) was accomplished by an in situ procedure in alkaline solution. A linear calibration plot for Pb(II) in the concentration range 40 to 6700 nmol L(-1) (r=0.998) was obtained, the detection limit was found to be 12.5 nmol L(-1) (S/N = 3) and the relative standard deviation in Solutions containing 1 mu mol L(-1) Pb(II) was 4% (n = 12). The analytical performance of the proposed sensor wits tested by measuring the Pb(II) concentration in a wine sample. The result Was in good agreement with the one obtained by GFAAS.; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Fundacao de Apoio a Pesquisa do Estado de Sao Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)

Ex Situ Scanning Electrochemical Microscopy (SECM) Investigation of Bismuth- and Bismuth/Lead Alloy Film-Modified Gold Electrodes in Alkaline Medium

SALLES, Maiara Oliveira; BATTISTEL, Dario; LIMA, Alex Silva; BERTOTTI, Mauro; DANIELE, Salvatore
Fonte: WILEY-BLACKWELL Publicador: WILEY-BLACKWELL
Tipo: Artigo de Revista Científica
ENG
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Scanning electrochemical microscopy (SECM) in feedback mode was employed to characterise the reactivity and microscopic peculiarities of bismuth and bismuth/lead alloys plated onto gold disk substrates in 0.1 molL(-1) NaOH solutions. Methyl viologen was used as redox mediator, while a platinum microelectrode was employed as the SECM tip. The metal films were electrodeposited ex situ from NaOH solutions containing either bismuth ions only or both bismuth and lead ions. Approach curves and SECM images indicated that the metal films were conductive and locally reactive with oxygen to provide Bi(3+) and Pb(2+) ions. The occurrence of the latter chemical reactions was verified by local anodic stripping voltammetry (ASV) at the substrate solution interface by using a mercury-coated platinum SECM tip. The latter types of measurements allowed also verifying that lead was not uniformly distributed onto the bismuth film electrode substrate. These findings were confirmed by scanning electron microscopy images. The surface heterogeneity produced during the metal deposition process, however, did not affect the analytical performance of the bismuth coated gold electrode in anodic stripping voltammetry for the determination of lead in alkaline media...

A New Indirect Electroanalytical Method to Monitor the Contamination of Natural Waters with 4-Nitrophenol Using Multiwall Carbon Nanotubes

MORAES, Fernando Cruz; TANIMOTO, Sonia Tomie; SALAZAR-BANDA, Giancarlo Richard; MACHADO, Sergio Antonio Spinola; MASCARO, Lucia Helena
Fonte: WILEY-V C H VERLAG GMBH Publicador: WILEY-V C H VERLAG GMBH
Tipo: Artigo de Revista Científica
ENG
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The electrochemical detection of the hazardous pollutant 4-nitrophenol (4-NP) at low potentials, in order to avoid matrix interferences, is an important research challenge. This study describes the development, electrochemical characterization and utilization of a multiwall carbon nanotube (MWCNT) film electrode for the quantitative determination of 4-NP in natural water. Electrochemical impedence spectroscopy measurements showed that the modified surface exhibits a decrease of ca. 13 times in the charge transfer resistance when compared with a bare glassy carbon (GC) surface. Voltammetric experiments showed the possibility to oxidize a hydroxylamine layer (produced by the electrochemical reduction of 4-NP on the GC/MWNCT surface) in a potential region which is approximately 700 mV less positive than that needed to oxidize 4-NP, thus minimizing the interference of matrix components. The limit of detection for 4-NP obtained using square-wave voltammetry (0.12 mu mol L(-1)) was lower than the value advised by EPA. A natural water sample from a dam located in Sao Carlos (Brazil) was spiked with 4-NP and analyzed by the standard addition method using thee GC/MWCNT electrode, without any further purification step. the recovery procedure yielded a value of 96.5% for such sample...

Graphite-silicone rubber composite electrode: Preparation and possibilities of analytical application

OLIVEIRA, Aline Carlos de; SANTOS, Sidney Xavier dos; CAVALHEIRO, Eder Tadeu Gomes
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
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Composite electrodes were prepared using graphite powder and silicone rubber in different compositions. The use of such hydrophopic materials interned to diminish the swallowing observed in other cases when the electrodes are used in aqueous solutions for a long time. The composite was characterized for the response reproducibility, ohmic resistance, thermal behavior and active area. The voltammetric response in relation to analytes with known voltammetric behavior was also evaluated, always in comparison with the glassy carbon. The 70% (graphite, w/w) composite electrode was used in the quantitative determination of hydroquinone (HQ) in a DPV procedure in which a detection limit of 5.1 x 10(-8) mol L-1 was observed. HQ was determined in a photographic developer sample with errors lower then 1% in relation to the label value. (c) 2007 Elsevier B.V. All rights reserved.

Analytical Potentialities of Carbon Nanotube/Silicone Rubber Composite Electrodes: Determination of Propranolol

SANTOS, Sidney Xavier dos; CAVALHEIRO, Eder T. G.; BRETT, Christopher M. A.
Fonte: WILEY-V C H VERLAG GMBH Publicador: WILEY-V C H VERLAG GMBH
Tipo: Artigo de Revista Científica
ENG
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151.45357%
A new composite electrode based on multiwall carbon nanotubes (MWCNT) and silicone-rubber (SR) was developed and applied to the determination of propranolol in pharmaceutical formulations. The effect of using MWCNT/graphite mixtures in different proportions was also investigated. Cyclic voltammetry and electrochemical impedance spectroscopy were used for electrochemical characterization of different electrode compositions. Propranolol was determined using MWCNT/SR 70% (m/m) electrodes with linear dynamic ranges up to 7.0 mu molL(-1) by differential pulse and up to 5.4 mu molL(-1) by square wave voltammetry, with LODs of 0.12 and 0.078 mu molL(-1), respectively. Analysis of commercial samples agreed with that obtained by the official spectrophotometric method. The electrode is mechanically robust and presented reproducible results and a long useful life.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Fundação para a Ciência e a Tecnologia de Portugal (FCT); CAPES/FCT[177/07]; Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); FAPESP-Brazil[08/03537-7]; CEMUC; CEMUC[285]; Fundação para a Ciência e a Tecnologia de Portugal (FCT); FCT, Portugal

Is the poly (methylene blue)-modified glassy carbon electrode an adequate electrode for the simple detection of thiols and amino acid-based molecules?

Costa Marinho, Maria Ines; Cabral, Murilo Feitosa; Mazo, Luiz Henrique
Fonte: ELSEVIER SCIENCE SA; LAUSANNE Publicador: ELSEVIER SCIENCE SA; LAUSANNE
Tipo: Artigo de Revista Científica
ENG
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This paper describes the preparation, characterization, and use of poly (methylene blue) (PMB)-modified glassy carbon electrodes (GCE) (GCE-PMB) in the detection of the thiols L-cysteine (L-CySH) and N-acetyl cysteine (Acy), and the herbicide glyphosate (GLYP) in pH 5.3 aqueous solution. The polymer film prepared by electropolymerization showed different characteristics such as robustness, stability, and redox properties satisfactorily. The surface coverage concentration (Gamma) of PMB was found to be 7.90 x 10(-9) - mol cm(-2). Moreover, we observed strong adhesion of the polymer film to the electrode surface. The results using GCE-PMB as a sensor indicated that this modified electrode exhibited electrocatalytic activity toward the detection of thiols and glyphosate in 0.1 mol L-1 KO (pH 5.3). Meanwhile, strong adsorption of the analytes on the GCE-PMB electrodes was also observed. Otherwise, using a low concentration (1 x 10(-4) mol L-1) of L-cysteine and N-acetyl cysteine and 8.9 x 10(-6) mol L-1 of glyphosate, separately, it was possible to observe a well-defined electrochemical response, thus providing an opportunity to further understand the applicability of PMB as a sensor for amino acid-based molecules. (C) 2012 Elsevier B.V. All rights reserved.; CAPES; CAPES [PNPD/CAPES 0316083]; FINEP; FINEP

Desenvolvimento de metodologias eletroanalíticas para determinação de pesticidas em óleo essencial de laranja; Development of electroanalytical methodologies for pesticides determination in orange essential oil

Andrade, Fernanda Ramos de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/08/2014 PT
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A citricultura, introduzida no Brasil na época da colonização e explorada comercialmente a partir dos anos 30 do século passado, é um setor de grande importância para o agronegócio brasileiro. Atualmente, o Brasil detém 50% da produção mundial de laranja e cerca de 85% de toda exportação mundial, representando uma captação de divisas de cerca de 2,5 bilhões de dólares por ano, devido principalmente à exportação do suco de laranja. Apesar do suco ser o principal produto de exportação da citricultura, vários subprodutos com valor comercial são obtidos durante seu processo de produção, tais como os óleos essenciais cítricos. Esses subprodutos localizam-se na casca da fruta e são obtidos durante o processo de extração do suco de laranja por prensagem a frio. Devido ao uso intensivo de pesticidas na citricultura e que muitas vezes se acumula na casca da fruta é comum à obtenção de óleos essenciais com resíduos de pesticidas, o que reduz seu preço de mercado internacional e limita sua inserção em mercados exigentes como o Europeu, Japonês e Americano, por exemplo. Este trabalho propõe o desenvolvimento de metodologias eletroanalíticas para a determinação de alguns pesticidas amplamente utilizados na citricultura brasileira e que têm sido encontrados nos óleos essenciais produzidos pelas indústrias de processamento. Inicialmente...

Electroanalysis of Heavy Metals in the Cork of Quercus Suber

Ponte-e-Sousa, João; Neto-Vaz, António; Teixeira, Jorge
Fonte: Portugaliae Electrochimica Acta Publicador: Portugaliae Electrochimica Acta
Tipo: Artigo de Revista Científica
ENG
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This will enable Pb(II) determination optimisation, regarding environmental aspects of the perpetuation of Quercus suber Montado (similar to Forest). It will also allow a more profound toxicological quality control of corks (barks). These two last referred aspects are very related ones, once accepted that the more advanced could the certification of the quality patterns of corks (barks) be, more will be the sustainability of Quercus suber ecosystem. Which we believe can be done, amongst other vectors, by studying such an important environmental issue as heavy metals. It is shown that Pb(II) quantification in the cork (bark) of Quercus suber tree (Cork Oak) is possible, using Differential Pulse Anodic Stripping Voltammetry (DPASV). The samples digestion was made in a mixture of H2O2 and HNO3 1:8, in a closed recipient at approximately 90 ºC. The measures were made in NaCl 0.1 M, using a Hanging Mercury Drop Electrode, a Glassy-Carbon Rod Counter Electrode, and an Ag/AgCl/KCl 3M reference electrode, after a 180 s deposition step. The results have shown the determination of a coherent stripping potential of -0.405 V (SD=0.0005 V), and a fine linear adjustment after the standard addition method (R2 = 0.997). They have also revealed the interest of further studies. The need to test other electroanalysis requisites was understood...

Dating copper-based archaeological materials using the voltammetry of microparticles

Doménech-Carbó, Antonio; Capelo, Sofia; Doménech-Carbó, María Teresa
Fonte: Universidade de Évora Publicador: Universidade de Évora
Tipo: Aula
ENG
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The voltammetry of microparticles, an electrochemical technique providing information on the composition of archaeological materials using an essentially non invasive analysis [1,2] was previously applied for dating lead-based materials [3,4]. It is described the application of this methodology for dating copper-based archaeological materials based on a theoretical model for long term metal corrosion [5]. Dating is based on the measurement of the voltammetric signals of cuprite and tenorite formed as a corrosion products in artifacts submitted to aging in atmospheric environments with no exigent corroding conditions. Assuming that the composition and conditions of aging can be considered as similar for all samples, and that the corrosion proceeded uniformly during the entire corrosion time, the time variation of the tenorite/cuprite ratio fits to a potential law from calibration using a set of copper-based coins. As a result, absolute dating can be obtained. References [1] Doménech, A.; Doménech, M.T.; Costa, V. Electrochemical methods applied to archaeometry, conservation and restoration, (Scholz, F. Edit.) Springer, Berlin-Heidelberg, 2009. [2] Doménech, A.; Doménech, M.T.; Pasíes, T.; Bouzas, M.C. Electroanalysis, 2011, 23...

Eletrodos quimicamente modificados aplicados à eletroanálise: uma breve abordagem

Souza,Maria de Fátima Brito
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/1997 PT
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Chemically modified electrodes (CMEs) have been subject of considerable attention since its inception about 23 years ago. CMEs result of a deliberate immobilization of a modifier agent onto the electrode surface obtained through chemical reactions, chemisorption, composite formation or polymer coating. This immobilization seeks transfer the physicochemical properties of the modifier to the electrode surface and thus to dictate and control the behavior of the electrode/solution interface. In recent years the interest in CMEs has increased particularly to enhance the sensitivity and/or the selectivity of electroanalytical techniques. In general higher sensitivity and/or selectivity may be achieved by exploiting one or more of the following phenomena: electrocatalysis, preconcentration and interferents exclusion. This paper deals with the application of CMEs in electroanalysis, including a brief presentation of the more general procedures that have been employed for the modification of electrode surfaces.

Construção de eletrodo de grafite retirado de pilha comum: aplicações didáticas

Baio,José Augusto Fragale; Ramos,Luiz Antônio; Cavalheiro,Éder Tadeu Gomes
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/07/2014 PT
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This paper presents a proposal for using recycled graphite electrodes obtained from exhausted commercial 1.5 V batteries and its application in electroanalysis. The electrode could be prepared by the students and applied in the simple didactic experiments suggested, such as determination of active electrode area, cyclic voltammetry and useful potential range (also called "potential window"), demonstration and effect of scan rate on cyclic voltammograms. The possibility of using the graphite electrode in quantitative analysis was also demonstrated using the ferricyanide/ferrocyanide reversible redox couple ([Fe(CN)6]3-/[Fe(CN)6]4-) as an electrochemical probe by the dependence of peak current with the analyte concentration and flow injection analysis with amperometric detection.

Flavonoid electrochemistry: a review on the electroanalytical applications

Gil,Eric S.; Cout,Renê O.
Fonte: Sociedade Brasileira de Farmacognosia Publicador: Sociedade Brasileira de Farmacognosia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
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Flavonoids are polyphenolic compounds widespread in vegetal kingdom. They present a C-15 skeleton, which is divided into three units A, B and C. Unit C is an oxygen containing heterocyclic, whose oxidation state and saturation level define major subclasses. Units A and B are aromatic rings, in which four major types of substituents, i. e. hydroxyl, methoxyl, prenyl and glycosides, lead to over 8000 different flavonoids. The great healthy-protecting value of these phytochemical biomarkers has attracted the attention of scientific community. Their main biological actions include anticancer and anti-inflammatory properties, which are strictly linked to antioxidant activities. So that, electroanalysis have been extensively applied on mechanistic studies and also for analytical determinations. This review presents the state of the art regarding the main applications of electroanalysis on the flavonoid research. The approaches on redox behavior characterization leading to a better understanding of structure antioxidant activity relationships are highlighted.

Online rapid sampling microdialysis (rsMD) using enzyme-based electroanalysis for dynamic detection of ischaemia during free flap reconstructive surgery

Rogers, M. L.; Brennan, P. A.; Leong, C. L.; Gowers, S. A. N.; Aldridge, T.; Mellor, T. K.; Boutelle, M. G.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
EN
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We describe an enzyme-based electroanalysis system for real-time analysis of a clinical microdialysis sampling stream during surgery. Free flap tissue transfer is used widely in reconstructive surgery after resection of tumours or in other situations such as following major trauma. However, there is a risk of flap failure, due to thrombosis in the flap pedicle, leading to tissue ischaemia. Conventional clinical assessment is particularly difficult in such ‘buried’ flaps where access to the tissue is limited. Rapid sampling microdialysis (rsMD) is an enzyme-based electrochemical detection method, which is particularly suited to monitoring metabolism. This online flow injection system analyses a dialysate flow stream from an implanted microdialysis probe every 30 s for levels of glucose and lactate. Here, we report its first use in the monitoring of free flap reconstructive surgery, from flap detachment to re-vascularisation and overnight in the intensive care unit. The on-set of ischaemia by both arterial clamping and failure of venous drainage was seen as an increase in lactate and decrease in glucose levels. Glucose levels returned to normal within 10 min of successful arterial anastomosis, whilst lactate took longer to clear. The use of the lactate/glucose ratio provides a clear predictor of ischaemia on-set and subsequent recovery...

Electroanalysis of NADH Using Conducting and Redox Active Polymer/Carbon Nanotubes Modified Electrodes-A Review

Kumar, S. Ashok; Chen, Shen-Ming
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 06/02/2008 EN
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Past few decades, conducting and redox active polymers play a critical role in the development of transducers for biosensing. It has been evidenced by increasing numerous reports on conducting and redox active polymers incorporated electrodes for assay of biomolcules. This review highlights the potential uses of electrogenerated polymer modified electrodes and polymer/carbon nanotubes composite modified electrodes for electroanalysis of reduced form of nicotinamide adenine dinuceltoide (NADH). In addition, carbon electrodes modified with organic and inorganic materials as modifier have been discussed in detail for the quantification of NADH based on mediator or mediator-less methods.

Electroanalysis of Heavy Metals in the Cork of Quercus Suber Tree. Preliminary Study: Electroanaliticity of Pb(II)

Sousa,J.C.A.C. Ponte e; Teixeira,J.M. Ginja; Vaz,A.M. Neto
Fonte: Sociedade Portuguesa de Electroquímica Publicador: Sociedade Portuguesa de Electroquímica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2003 EN
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This will enable Pb(II) determination optimisation, regarding environmental aspects of the perpetuation of Quercus suber Montado (similar to Forest). It will also allow a more profound toxicological quality control of corks (barks). These two last referred aspects are very related ones, once accepted that the more advanced could the certification of the quality patterns of corks (barks) be, more will be the sustainability of Quercus suber ecosystem. Which we believe can be done, amongst other vectors, by studying such an important environmental issue as heavy metals. It is shown that Pb(II) quantification in the cork (bark) of Quercus suber tree (Cork Oak) is possible, using Differential Pulse Anodic Stripping Voltammetry (DPASV). The samples digestion was made in a mixture of H2O2 and HNO3 1:8, in a closed recipient at approximately 90 ºC. The measures were made in NaCl 0.1 M, using a Hanging Mercury Drop Electrode, a Glassy-Carbon Rod Counter Electrode, and an Ag/AgCl/KCl 3M reference electrode, after a 180 s deposition step. The results have shown the determination of a coherent stripping potential of -0.405 V (SD=0.0005 V), and a fine linear adjustment after the standard addition method (R² = 0.997). They have also revealed the interest of further studies. The need to test other electroanalysis requisites was understood...