JBCS

23:53, Mon Sep 15

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Current Issue vol. 25, No. 9, 2014, p. 1537-1753



Cover Article
J. Braz. Chem. Soc. 2014, 25(9), 1647-1655

Bacterial Cellulose as a Template for Preparation of Hydrotalcite-Like Compounds

Gustavo F. Perotti; Hernane S. Barud; Sidney J. L. Ribeiro; Vera R. L. Constantino

How to cite this article

Bundles of cellulose secreted by Gluconacetobacter xylinus bacteria comprise a random net-like three dimensional network. This material, known as bacterial cellulose (BC), also presents large pores when hydrated, resulting in a vast interface for interactions that can influence the inorganic particles growing. In view of bioinspired routes to materials synthesis, BC was used as a template for preparation of layered double hydroxides (LDHs), a versatile class of materials applied in catalysis, adsorption, polymer and pharmaceutical fields. The BC presence in the inorganic layers formation process (involving the sharing of M(OH)6 octahedra) changes the LDH particles shape and increases the surface area. Details are presented in the Article Bacterial Cellulose as a Template for Preparation of Hydrotalcite-Like Compounds by Gustavo F. Perotti, Hernane S. Barud, Sidney J. L. Ribeiro and Vera R. L. Constantino on page 1647.

http://dx.doi.org/10.5935/0103-5053.20140153

Published online: July 1, 2014
Articles J. Braz. Chem. Soc. 2014, 25(9), 1537-1544

Voltammetric Determination of Gabapentin by a Carbon Ceramic Electrode Modified with Multiwalled Carbon Nanotubes and Nickel-Catechol Complex

Fahimeh Jalali; Zahra Hassanvand; Parisa S. Dorraji

How to cite this article

 

Nickel-catechol complex (Ni-CA) was deposited electrochemically on the surface of a multiwalled carbon nanotube-modified carbon ceramic electrode (MWCNT-CCE) at pH 13. Cyclic voltammetry showed a quasi-reversible behavior for the redox pair of Ni(III)/Ni(II). The modified electrode had electrocatalytic activity in the oxidation of gabapentin (GP).

http://dx.doi.org/10.5935/0103-5053.20140137

Published online: June 10, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1545-1551

Kinetics and Mechanism of Oxidation of Glycine and Alanine by Oxone® Catalyzed by Bromide Ion

Malharrao R. Thombare; Gavisiddappa S. Gokavi

How to cite this article

 

Oxidation of glycine and alanine by bromine generated in situ by Oxone®-bromide mixture proceeds through complex formation between bromine and the anion of the amino acid.

http://dx.doi.org/10.5935/0103-5053.20140139

Published online: June 13, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1552-1564

Discrimination of Black Pen Inks on Writing Documents Using Visible Reflectance Spectroscopy and PLS-DA

Verônica A. G. da Silva; Márcio Talhavini; Jorge J. Zacca; Bruno R. Trindade; Jez W. B. Braga

How to cite this article

 

Fast and nondestructive ink identification in handwritten questioned documents by visible spectroscopy and chemometric analysis.

http://dx.doi.org/10.5935/0103-5053.20140140

Published online: June 13, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1565-1570

TAG, DAG and FFA Profiles of Dry-Cured Ham by Easy Ambient Sonic-Spray Ionization Mass Spectrometry After Thermal Imprinting

Gabriel D. Fernandes; Wenceslao Moreda; Daniel Barrera-Arellano; Guilherme C. N. Z. Ruiz; Pedro L. Ferreira; Marcos N. Eberlin; Rosana M. Alberici

How to cite this article

 

Thermal imprinting easy ambient sonic-spray ionization mass spectrometry (TI-EASI-MS) was applied to direct lipid analysis of dry-cured ham. Triacylglycerols, diacylglycerols and free fatty acids were identified, according to the process and the rearing systems of pigs.

http://dx.doi.org/10.5935/0103-5053.20140141

Published online: June 13, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1571-1582

Validation Method to Determine Metals in Atmospheric Particulate Matter by Inductively Coupled Plasma Optical Emission Spectrometry

Luciana M. B. Ventura; Beatriz S. Amaral; Kristine B. Wanderley; José M. Godoy; Adriana Gioda

How to cite this article

 

Filters were placed in high-volume sampler to capture atmospheric particles for subsequent validation of methodology in order to determine concentrations of metals such as Cd, Cu, Pb, V and others that can cause health problems.

http://dx.doi.org/10.5935/0103-5053.20140142

Published online: June 18, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1583-1591

Multivariate Optimization of the QuEChERS-GC-ECD Method and Pesticide Investigation Residues in Apples, Strawberries, and Tomatoes Produced in Brazilian South

Juliana G. Lorenz; Léa L. F. Costa; Eliane A. Suchara; Ernani S. Sant'Anna

How to cite this article

 

Multivariate optimization of important variables of the QuEChERS method coupled to GC-ECD and investigation of the levels of pesticide residues in fruits and vegetables commercialized in Santa Catarina state, South of Brazil.

http://dx.doi.org/10.5935/0103-5053.20140143

Published online: June 18, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1592-1600

Metal Glycerolates as Catalysts in the Transesterification of Refined Soybean Oil with Methanol under Reflux Conditions

Fábio da Silva Lisboa; Fabiano Rosa da Silva; Claudiney Soares Cordeiro; Luiz Pereira Ramos; Fernando Wypych

How to cite this article

 

Layered divalent metal glycerolates were synthesized, characterized and used as catalyst in the transesterification of refined soybean oil. Almost complete conversions were obtained under mild reaction conditions and calcium diglycerolate preserved the structure up to three cycles of use.

http://dx.doi.org/10.5935/0103-5053.20140144

Published online: June 18, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1601-1606

Application of a Low Pressure Spray Chamber for the Determination of Mercury Concomitantly to other Trace Elements by Inductively Coupled Plasma Mass Spectrometry

Jefferson S. de Gois; Daniel L. G. Borges

How to cite this article

 

Mercury determination by inductively coupled plasma mass spectrometry using conventional sample introduction systems is affected by significant memory effect. In order to overcome this difficulty, a new sample introduction setup employing a low pressure spray chamber was developed.

http://dx.doi.org/10.5935/0103-5053.20140145

Published online: June 25, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1607-1613

Synthesis of Thermoplastic Starch-Bacterial Cellulose Nanocomposites via in situ Fermentation

Marlon A. Osorio; David Restrepo; Jorge A. Velásquez-Cock; Robin O. Zuluaga; Ursula Montoya; Orlando Rojas; Piedad F. Gañán; Diana Marin; Cristina I. Castro

How to cite this article

 

Chemical crosslinking. Citric acid attaches to the thermoplastic starch (TPS) chains and bacterial cellulose (BC) nanoribbons through covalent bonds.

http://dx.doi.org/10.5935/0103-5053.20140146

Published online: June 25, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1614-1620

Electrocatalytic Detection of Glutathione - the Search for New Mediators

Denise Lowinsohn; Patricia T. Lee; Richard G. Compton

How to cite this article

 

Electrocatalytic reaction between electrochemically generated quinoneimines and glutathione and the resulting voltammograms.

http://dx.doi.org/10.5935/0103-5053.20140147

Published online: June 25, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1621-1629

Determination of Sn2+ in Lyophilized Radiopharmaceuticals by Voltammetry, Using Hydrochloric Acid as Electrolyte

Adilio da S. Dadda; Ariane da C. Teixeira; Paula K. Feltes; Maria M. Campos; Carlos E. Leite; Cristina M. Moriguchi-Jeckel

How to cite this article

 

This paper describes a method for selective determination of Sn+2 by voltammetry, using 1 mol L-1 hydrochloric acid as electrolyte.

http://dx.doi.org/10.5935/0103-5053.20140148

Published online: June 25, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1630-1637

Simultaneous Determination of Isoproterenol, Acetaminophen and Folic Acid Using Nanostructured Electrochemical Sensor Based on Benzofuran Derivative and Carbon Nanotubes

Mohammad Mazloum-Ardakani; Seyyed H. Ahmadi; Zohal S. Mahmoudabadi; Alireza Khoshroo

How to cite this article

 

A carbon paste electrode chemically modified with multiwall carbon nanotubes was prepared and used as a selective electrochemical sensor for the simultaneous determination of isoproterenol, acetaminophen and folic acid.

http://dx.doi.org/10.5935/0103-5053.20140151

Published online: June 27, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1638-1646

Using Webcam, CdTe Quantum Dots and Flow-Batch System for Automatic Spectrofluorimetric Determination of N-Acetyl-L-cysteine in Pharmaceutical Formulations

Marcelo B. Lima; Inakã S. Barreto; Stéfani Iury E. Andrade; Luciano F. Almeida; Mário César U. Araújo

How to cite this article

 

A flow-batch system using cadmium telluride quantum dots (CdTe QDs) and webcam for spectrofluorimetric determination of N-acetyl-L-cysteine in pharmaceutical formulations.

http://dx.doi.org/10.5935/0103-5053.20140152

Published online: June 27, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1647-1655

Bacterial Cellulose as a Template for Preparation of Hydrotalcite-Like Compounds

Gustavo F. Perotti; Hernane S. Barud; Sidney J. L. Ribeiro; Vera R. L. Constantino

How to cite this article

 

Polysaccharide bacterial cellulose (BC) was used as a template for preparation of Hydrotalcite-type compounds or layered double hydroxides (LDHs) by a bio-inspired route. The changes in LDH particles morphology and the improvement in surface area can be driven by the cation-binding on the BC surface. Novel synthetic routes that lead to materials with particular morphology and surface area are interesting to produce catalysts and drug delivery systems.

http://dx.doi.org/10.5935/0103-5053.20140153

Published online: July 1, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1656-1661

Simple Method to Determine Residual Cypermethrin and Deltamethrin in Bovine Milk

Thais Hernandes; Eliana F. G. C. Dores; Maria L. Ribeiro; Paulo A. Rossignoli; Olaf Malm

How to cite this article

 

This article presents a simple method, applied to a complex matrix for quantification of fat-soluble pesticides. The validated method was applied to twenty milk samples collected in small dairy farms in the Municipality of Chapada dos Guimarães, Mato Grosso, Brazil, a Brazilian understudied region.

http://dx.doi.org/10.5935/0103-5053.20140154

Published online: July 1, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1662-1666

Direct Determination of Oleic Acid in Soybean Oil by Capacitively Coupled Contactless Conductivity Detection Capillary Electrophoresis in an Oil-Miscible KOH/1-Propanol/Methanol Medium

Wolmir José Böckel; Yara Patrícia da Silva; Carla R. B. Mendonça; Ernesto F. Simó-Alfonso; Guillermo Ramis-Ramos; Clarisse M. S. Piatnicki

How to cite this article

 

Capillary electrophoresis with capacitively coupled contactless conductivity detection for the direct determination of oleic acid content in soybean oil using salicylic acid as internal standard. Under negative polarity, the anionic solutes moved faster than the electro osmotic flow.

http://dx.doi.org/10.5935/0103-5053.20140155

Published online: July 1, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1667-1672

Fingerprinting Breath: Electrochemical Monitoring of Markers Indicative of Bacteria Mycobacterium tuberculosis Infection

Jonathan P. Metters; Dimitrios K. Kampouris; Craig E. Banks

How to cite this article

 

Exploring the potential electrochemical determination of markers (methyl phenyl acetate, methyl p-anisate, methyl nicotinate and 2-methoxybiphenyl) proposed to be indicative of Mycobacterium tuberculosis infection.

http://dx.doi.org/10.5935/0103-5053.20140159

Published online: July 4, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1673-1680

Degradation of Dipyrone by the Electro-Fenton Process in an Electrochemical Flow Reactor with a Modified Gas Diffusion Electrode

Willyam R. P. Barros; Michelle P. Borges; Rafael M. Reis; Robson S. Rocha; Rodnei Bertazzoli; Marcos R. V. Lanza

How to cite this article

 

The GA represents the molecular structure of dipyrone as well as the commercial capsules drug. It is also shown the UV-Vis spectrum of the initial aqueous solution of 50 mg L-1 of dipyrone and after 90 min of electrochemical treatment, where the maximum absorption occurs at around 1.2 at wavelength 262 nm.

http://dx.doi.org/10.5935/0103-5053.20140160

Published online: July 4, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1681-1687

Liquid Chromatography-Orbitrap Mass Spectrometry Method for the Determination of Toxic Glycoalkaloids and their Aglycons in Potato Upper Soil

Giovanni Caprioli; Michael G. Cahill; Kevin J. James; Sauro Vittori

How to cite this article

 

α-solanine and α-chaconine are the two main potato glycoalkaloids, toxic at certain levels, that may be persistent in the terrestrial environment. A new analytical method that uses liquid chromatography Orbitrap mass spectrometry has been developed for the analysis of the two glycoalkaloids and theirs aglycons in potato upper soils.

http://dx.doi.org/10.5935/0103-5053.20140161

Published online: July 4, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1688-1695

Synthesis of Unsymmetrical Aryl-Ethynylated Benzenes via Regiocontrolled Sonogashira Reaction of 1,3,5-Tribromobenzene

Kamal M. Dawood; Hamdi M. Hassaneen; Hyam A. Abdelhadi; Mohamed S. M. Ahmed; Mohamed A.-M. Mohamed

How to cite this article

 

Regiocontrolled Sonogashira cross-coupling of 1,3,5-tribromobenzene with the terminal (4-alkoxyaryl)acetylenes yielded mono-, di- and tri-alkynylated benzene derivatives in moderate to good yields.

http://dx.doi.org/10.5935/0103-5053.20140163

Published online: July 15, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1696-1703

Quantification of Cocaine Hydrochloride in Seized Drug Samples by Infrared Spectroscopy and PLSR

Tatiane S. Grobério; Jorge J. Zacca; Marcio Talhavini; Jez W. B. Braga

How to cite this article

 

Direct analysis of cocaine hydrochloride in drug samples without any sample preparation by infrared and PLS analysis.

http://dx.doi.org/10.5935/0103-5053.20140164

Published online: July 15, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1704-1711

Production of Biodiesel Catalyzed by Candida rugosa Lipase at Interface of w/o Microemulsion System

Zhongqin Tan; Miaoli Fang; Huan Du; Lelian Song; Dahai Ren; Xiujuan Tang; Xiaoxiang Han; Xinle Liang

How to cite this article

 

In this study, lipase showed a good activity in the w/o microemulsion system, which served as a host for water-soluble enzymes.

http://dx.doi.org/10.5935/0103-5053.20140165

Published online: July 15, 2014

J. Braz. Chem. Soc. 2014, 25(9), 1712-1719

A Simple, Fast and Efficient Method for Transesterification of Fatty Acids in Foods Assisted by Ultrasound Energy

Oscar O. Santos Júnior; Paula F. Montanher; Elton G. Bonafé; Ivanor N. do Prado; Swami A. Maruyama; Makoto Matsushita; Jesuí V. Visentainer

How to cite this article

 

Through the combination of alkaline and acid catalysts, low frequency ultrasound, and response surface methodology, a new fatty acid methylation method with minimal ester oxidation was developed, optimized and validated.

http://dx.doi.org/10.5935/0103-5053.20140166

Published online: July 15, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1720-1729

Retention of Carbamate Pesticides by Different Surfactant-Modified Sorbents: a Comparative Study

Prapha Arnnok; Rodjana Burakham

How to cite this article

 

Three surfactant-modified sorbents were created for carbamate pesticides sorption and their application for the extraction of carbamate pesticides prior to HPLC analysis was demonstrated.

http://dx.doi.org/10.5935/0103-5053.20140167

Published online: July 18, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1730-1736

Microwave Assisted Biodiesel Production from Trap Grease

Paulo S. R. Fernandes; Luiz E. P. Borges; Carlos E. G. de Carvalho; Rodrigo O. M. A. de Souza

How to cite this article

 

In this paper, trap grease catalytic esterification with methanol was performed under microwave irradiation providing high conversion with relatively short reaction time.

http://dx.doi.org/10.5935/0103-5053.20140169

Published online: July 25, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1737-1745

Nanostructured Screen-Printed Electrodes Modified with Self-Assembled Monolayers for Determination of Metronidazole in Different Matrices

Bryan C. Huayhuas-Chipana; Juan C. M. Gomero; Maria D. P. T. Sotomayor

How to cite this article

 

A technique was successfully developed for the determination of metronidazole in pharmaceutical and biological samples using a sensor based on a nanostructured screen-printed gold electrode obtained using a simple metal pre-treatment process followed by modification with a SAM of cysteine. The proposed sensor is a potential candidate for mass construction and miniaturization.

http://dx.doi.org/10.5935/0103-5053.20140170

Published online: July 25, 2014
J. Braz. Chem. Soc. 2014, 25(9), 1746-1753

Continuous Production of Biodiesel in Supercritical Ethanol: A Comparative Study between Refined and Used Palm Olein Oils as Feedstocks

Somkiat Ngamprasertsith; Chafi-ee Laetoheem; Ruengwit Sawangkeaw

How to cite this article

 

After use of refined palm oil for frying chicken, level of free fatty acid (FFA) and unsaturated fatty acids (UFAs) increased. Due to the antagonistic effect of UFAs and FFA, the ester content of used palm oil biodiesel was slightly lower than for refined palm oil biodiesel.

http://dx.doi.org/10.5935/0103-5053.20140171

Published online: July 25, 2014

Online version ISSN 1678-4790 Printed version ISSN 0103-5053
Journal of the Brazilian Chemical Society
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