Regina Massako Takeuchi

Regina Massako Takeuchi
Federal University of Uberlândia | UFU · Institute of Exact and Natural Sciences of Pontal (ICENP)

Professor

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55
Publications
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1,115
Citations

Publications

Publications (55)
Article
Even though ammonia is a natural component of aquatic environments, elevated concentrations indicate pollution and environmental degradation. Consequently, efficient analytical methods for monitoring ammonia levels are crucial for preserving water quality. Voltammetry offers a sustainable approach for NH 3 quantification, combining good analytical...
Article
Thread-based microfluidic analytical devices have received growing attention since threads have some advantages over other materials. Compared to paper, threads are also capable of spontaneously transporting fluid due to capillary action, but they have superior mechanical strength and do not require hydrophobic barriers. Therefore, thread-based mic...
Article
Electroanalytical methods are suitable to quantify pharmaceutical compounds. The typically high cost for preparing many electrochemical sensors, however, has been a drawback to their widespread use. We have used inexpensive graphite sheets (GS) as conductive substrates, and modified them by electropolymerizing a film of poly(methylene blue) (PMB) b...
Article
Voltammetry and amperometry are inexpensive and high-performance analytical techniques. However, their lack of selectivity limits their use in complex matrices such as biological, environmental, and food samples. Therefore, voltammetric and amperometric analyses of these samples usually require time-consuming and laborious sample pretreatments. In...
Article
Conducting films were produced by incorporating 35, 50, and 60 wt.%. of graphite in cellulose acetate. The graphite contents showed to be of pivotal importance to the properties of the materials, mainly on the electrochemical performance. Thermal analyses indicated the graphite hinders the crystallization process of cellulose acetate and increases...
Article
The monitoring of species of medical, environmental, and industrial interests has been urgently demanded. Several times, the necessity of point of care and/or point of use is important to obtain precise and rapid quantification, in which wearable and flexible disposable electrochemical sensors and biosensors have been great alternatives. In this co...
Article
Miniaturization of analytical devices is a new and perhaps the ultimate trend in analytical chemistry. However, many microfabrication techniques could be inaccessible for researchers from developing countries where research funding is routinely scarce. Thus, in this study, we describe an approach to fabricate an inexpensive and durable miniaturized...
Article
This study reports a new electrochemical method for tryptamine determination using a paper-based microfluidic device and a thermoplastic electrode (TPE) as an amperometric detector. Tryptamine (Tryp) is a biogenic amine present in drinks and foods. Even though this compound has some beneficial effects on human health, the ingestion of foods with hi...
Article
Full-text available
The suitable combination of active pharmaceutical molecules and polymer matrices is a key factor for the development of systems for controlled release. The proper choice of the bioactive species/polymer pair depends strongly on the dispersion capacity and the interaction established between the bioactive species in the polymer matrix. Solid dispers...
Article
Lactose (LAC) is a disaccharide - major sugar, present in milk and dairy products. LAC content is an important indicator of milk quality and abnormalities in food industries, as well as in human and animal health. The present study reports the development of an innovative imprinted voltammetric sensor for sensitive detection of LAC. The sensor was...
Chapter
Zinc Oxide as a Multifunctional Material: From Biomedical Applications to Energy Conversion and Electrochemical Sensing. Zinc oxide (ZnO) is a very attractive material which has received growing attention in the academic and technological areas. This metal oxide shows several advantageous properties such as facile and inexpensive synthesis, low to...
Patent
A presente invenção pertence ao campo da química e ao campo de polímeros. A invenção refere-se a uma nova composição de tinta condutora de eletricidade, incluindo pelo menos uma espécie condutora, sendo tal espécie condutora composta por grafeno em pó e base de esmalte para unhas, além de processo para sua produção através da tecnologia de mistura...
Article
This study describes the fabrication of carbon screen-printed electrodes (SPEs) from alternative and low-cost materials. The carbon conductive ink was prepared from a mixture of graphite powder and colorless nail polish. To produce the SPEs, the ink was spread on polyester overhead projector sheets, which acted as a flexible and water-impermeable s...
Article
A simple and low-cost continuous flow (CF) electrochemical paper-based analytical device (ePAD) coupled with thermoplastic electrodes (TPE) was developed. The fast, continuous flow combined with flow injection analysis was made possible by adding two inlet reservoirs to the same paper-based hollow channel flowing over detection electrodes, terminat...
Article
Nowadays, there is growing interest in portable and disposable electrochemical sensors due to the low-cost, simplicity, and excellent analytical performance associated with these devices. Despite recent advances, however, there remains a need to create cheap, high-performance electrode materials. Thus, this study evaluated the suitability of carbon...
Article
Full-text available
Cellulose derivatives still receive special attention in today biomedical applications due to their biocompatibility, ability to form resistant membranes and compatibility with various bioactive agents. In this work, cellulose acetate (CA) was used to prepare membranes with different morphologies aiming to evaluate the release profile of the drug i...
Article
Full-text available
This study describes the use of uncured polydimethylsiloxane (PDMS) as a binder agent to prepare carbon paste electrodes (CPEs). A comparative study between the properties of CPEs prepared with PDMS and mineral oil Nujol®, the most common binder agent for CPEs, was carried out. Cyclic voltammetry, electrochemical impedance spectroscopy, and chronoa...
Article
Full-text available
This work presents a voltammetric method for Zn²⁺ determination in antiseptic dusting powder and multivitamin commercial samples, combining an alkaline extraction using NaOH aqueous solution with a carbon paste electrode chemically modified with Bi anchored on Amberlite® IR120 ion exchange resin (CPEAmb/Bi). The best conditions for electrode prepar...
Article
A simple and inexpensive procedure of paper-based electrode (PE) fabrication using A4 size conventional paper, nail polish and carbon powder is reported. The device was prepared by spreading the carbon conductive ink directly onto the paper substrate using a paint-brush. The best composition of the conductive ink was 80:20% (m:m) carbon powder: nai...
Article
In this study, a square wave anodic stripping voltammetric method was developed to quantify Bi3+ in eye shadow samples. The best results were obtained in 1.0 mol L-1 NaOH as the supporting electrolyte and the limit of detection was 8 nmol L-1 (1.7 ppb). Different sample pretreatment procedures were evaluated and the results showed that concentrated...
Article
Full-text available
The development of a miniaturized electrochemical cell to be applied to didactical experiments involving cyclic voltammetry is presented. The main objective is proposing an experiment for undergraduate courses within the concepts of Green Analytical Chemistry and involves the learning of electrochemistry and analytical chemistry concepts. The elect...
Article
In this study, a carbon paste electrode was used for the amperometric detection of atenolol (ATN) in a Flow Injection Analysis (FIA) system with recirculation of the carrier solution. Under optimized conditions, the FIA method presented a linear range from 50 to 1000 μmol L⁻¹, with a limit of detection of 8 μmol L⁻¹ and a limit of quantification of...
Article
Full-text available
This paper describes a comparative study between the procedures of deconvolution and the second-order derivative of square wave voltammograms to achieve separation of the voltammetric peaks of levofloxacin (LEVO) and norfloxacin (NOR), for their simultaneous quantification in urine samples. The obtained results indicate that the use of second-deriv...
Article
A selective, simple, and low cost method for nitrite determination was developed using an FIA system with a Prussian blue-carbon paste electrode (PB-CPE) as an amperometric detector. The electrochemical sensor was prepared by a fast, simple, and inexpensive procedure, and the long-term stability of the electrode was quite satisfactory as the perfor...
Article
The suitability of LSV to study adsorption kinetics of metal ions was evaluated using Cu2+ adsorption on Amberlite� IR-120 as a model system. LSV provided results in agreement with conventional batch method with remarkable decreasing on analysis time and reagents consumption, since no adsorbent/adsorbate separation is required. Adsorption curves ca...
Article
Full-text available
In this work, a voltammetric method for determination of nitrite in tap and mineral waters samples was developed. The method is based on the reduction of nitrite catalyzed by the electrochemical mediator [Fe(CN)6]3-. A carbon paste electrode (CPE) prepared with solid paraffin as binder agent was used as working electrode and cyclic voltammetry was...
Article
Full-text available
In this work a bismuth film electrode (BiFE) plated in situ onto glassy carbon was used to quantify Zn2+ in multivitamin formulation samples by square wave anodic stripping voltammetry. For partially water-soluble multivitamin tablets, an alkaline extraction with 1.0 mol L−1 NaOH aqueous solution was adopted. This procedure was simple, fast and eff...
Article
Full-text available
This work reports the successful use of square-wave voltammetry (SWV) to directly assess the controlled releasing profile of naproxen from lab-made cellulose derivative materials (membranes and microparticles) in phosphate buffer (pH 7.4) at 36 °C. Particular advantage of SWV refers to the direct real-time monitoring of released drug from cellulose...
Article
j o u r n al h o m ep ag e: w w w . o r b i t al . u f m s . b r ISSN 1984-6428  Vol 6   No. 4   October-December 2014  Full Paper Abstract: In this work a carbon paste electrode chemically modified with an ionic liquid (CPE-IL) was used to quantify the antioxidant propyl gallate (PG) in spiked soybean biodiesel samples by square wave voltamm...
Article
Full-text available
In this work a carbon paste electrode chemically modified with an ionic liquid (CPE-IL) was used to quantify the antioxidant propyl gallate (PG) in spiked soybean biodiesel samples by square wave voltammetry. Under the optimized conditions, the proposed method have presented a linear range from 2.0 to 47.5 μmol L -1 , with limit of detection equal...
Article
Full-text available
j o u r n al h o m ep ag e: w w w . o r b i t al . u f m s . b r ISSN 1984-6428  Vol 6   No. 4   October-December 2014  Full Paper Abstract: In this work a carbon paste electrode chemically modified with an ionic liquid (CPE-IL) was used to quantify the antioxidant propyl gallate (PG) in spiked soybean biodiesel samples by square wave voltamm...
Article
Full-text available
Recebido em 13/03/2014; aceito em 30/04/2014; publicado na web em 15/07/2014 DEVELOPMENT OF A FLOW INJECTION ANALYSIS SYSTEM EMPLOYNG ALTERNATIVE AND LOW-COST MATERIALS FOR DIDACTIC PURPOSES. This work describes a simple and inexpensive flow injection analysis system in which gravity force provides fluid propulsion while needles for insulin adminis...
Article
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j o u r n a l h o m e p a g e : w w w . o r b i t a l . u f m s . b r ISSN 1984-6428  Vol 6   No. 1   January-March 2014  Full Paper Abstract: In this work, bismuth films were electrodeposited in situ onto carbon paste electrodes (CPEs) and they were used for lead determination in tap water samples by anodic stripping square wave voltammetry....
Article
This article critically reviews the electroanalytical methods devoted for the determination of organic compounds in automotive fuels that can range from contaminants to additives typically introduced into liquid biofuels and liquid fossil fuels. Contaminants such as aldehydes and ketones in bioethanol, free fatty acids and glycerol in biodiesel, an...
Chapter
Full-text available
A utilização de bicombustíveis, principalmente em veículos motoriza-dos, constitui atualmente uma alternativa de grande viabilidade em diver-sas matrizes energéticas de vários países. Desta forma, o bioetanol, etanol derivado da biomassa, destaca-se pela possibilidade de ser utilizado como combustível propriamente dito (hidratado) e também como adi...
Article
A voltammetric method for the determination of ethyl acetate in ethanol fuel using a Fe3+/Nafion®-coated glassy carbon electrode (GCE) is proposed. The ethyl acetate present in the ethanol fuel was previously converted to acetohydroxamic acid via pretreatment with hydroxylamine chloride. The acetohydroxamic acid promptly reacted with the iron (III)...
Article
In this work, an adsorptive cathodic stripping voltammetric method based on square wave voltammetry (SWV) was developed for determination of the sunscreen agent octocrylene (OCR) individually and simultaneously with 2-Hydroxy-4-methoxybenzophenone (BENZO-3) and octyl methoxycinnamate (OMC). All voltammetric experiments were conducted in a mixture 0...
Article
This article critically reviews the electroanalytical methods developed for the determination of inorganic contami-nants in automotive fuels. Topics include the methods applied to the analysis of liquid biofuels and liquid fossil fuels for which different strategies were developed based on analytes and sample matrices. Special attention is given to...
Article
Full-text available
A solid paraffin-based carbon paste electrode modified with 2-aminothiazole-silica-gel (SPCPE-SiAt) was used for direct quantification of Cu 2+ in sugarcane spirits (cachaça) samples by anodic stripping voltammetry. The composite formed between carbon powder and solid paraffin was totally stable in ethanol/water mixtures enabling the quantification...
Article
Full-text available
A solid paraffin-based carbon paste electrode modified with 2-aminothiazole functionalized silica-gel was used for simultaneous quantification of Pb2+ and Cu2+ in water samples by anodic stripping voltammetry. The present method uses short preconcentration time (180 s), which allowed reliable and simultaneous quantification of Pb2+ and Cu2+ in a ve...
Article
Full-text available
grupos 2-aminotiazol foi empregado na quantificação simultânea de Pb 2+ e Cu 2+ em amostras de água por meio de voltametria de redissolução anódica. O presente método emprega um tempo curto de pré-concentração (180 s), o qual permitiu a quantificação simultânea e confiável de Pb 2+ e Cu 2+ de maneira bastante rápida. Foram obtidos limites de detecç...
Chapter
Full-text available
This article critically reviews the electroanalytical methods developed for the determination of inorganic contaminants in automotive fuels. Topics include the methods applied to the analysis of liquid biofuels and liquid fossil fuels for which different strategies were developed based on analytes and sample matrices. Special attention is given to...
Article
A linear sweep anodic stripping voltammetric method was developed for copper determination in commercial ethanol fuel samples by using a gold microelectrode. Under the optimized conditions, a linear range from 0.05 to 1.0μM was obtained, with detection limit of 22nM. The method was employed to determine copper ions in six commercial ethanol fuel sa...
Article
Full-text available
Drug analysis is important in several phases of drug development, such as formulation, stability studies and quality control. The importance of reliable analytical methods for drug determination in a fast, inexpensive, sensitive and selective way is thus evident. Although there are countless works describing new analytical methods for determination...
Article
Full-text available
The electrochemical reduction of amoebicide Teclozan (TEC) was studied on a glassy carbon electrode in acetonitrile. Controlled-potential electrolyses were performed for coulometric and preparative purposes. The electrogenerated products were isolated by liquid-liquid extraction and characterized by (1)H NMR. It was observed that TEC presents two v...
Article
A solid paraffin-based carbon paste electrode modified with 2-aminothiazole organofunctionalized silica (SiAt-SPCPE) was applied to Ni(2+) determination in commercial ethanol fuel samples. The proposed method comprised four steps: (1) Ni(2+) preconcentration at open circuit potential directly in the ethanol fuel sample, (2) transference of the elec...
Article
Solid paraffin-based carbon paste electrodes modified with 2-aminothiazole organofunctionalized silica have been applied to the anodic stripping determination of copper ions in ethanol fuel samples without any sample treatment. The proposed method comprised four steps: (1) copper ions preconcentration at open circuit potential directly in the ethan...
Article
Full-text available
The electrochemical reduction of diloxanide furoate (DF) in acetonitrile on glassy carbon electrode was studied in this work. It was observed that DF is reduced after a reversible one-electron transfer followed by an irreversible chemical reaction, diagnosed as C-Cl bond cleavage. Its reduction was followed by linear (LSV), differential pulse (DPV)...
Article
In this work, electrochemical oxidation of albendazole (ABZ) was carried out using a glassy carbon-rotating disk electrode. Development of electroanalytical methodology for ABZ quantification in pharmaceutical formulations was also proposed by using linear sweep voltammetric technique. Electrochemical oxidation is observed for ABZ at E(1/2)=0.99 V...
Article
The production of glassy polymeric carbon (GPC) through the thermal treatment of a phenolic resin is described. The pyrolysis process has been investigated by Fourier-transform infrared spectroscopy and powder X-ray diffraction. The final material is a conductive, nonporous, glasslike material with a rigid structure that can be used as a working el...
Conference Paper
Full-text available
The present work describes the production of glassy polymeric carbon from phenol formaldehyde resins by using different heating rates for each step of pyrolysis. The final product is a suitable material that can be used as electrode for monitoring charge transfer reactions or as supporting electrode for electroactive polymers. The obtained material...
Article
Full-text available
The present work describes the production the production of glassy polymeric carbon from phenol formaldehyde resins by using different heating rates for each step of pyrolysis. The final product is a suitable material that can be used as electrode for monitoring charge transfer reactions or as supporting electrode for electroactive polymers. The ob...

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