bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sensitive spectrophotometric determination of lamotrigine in bulk drug and pharmaceutical formulations using bromocresol green
Authors: Rajendraprasad Nagaraju , Kanakapura Basavaiah , Vinay Kanakapura Basavaiah 
Published: February 2018

Two new, simple, rapid and reproducible spectrophotometric methods have been developed for the determination of lamotrigine (LMT) both in pure form and in its tablets. The first method (method A) is based on the formation of a colored ion-pair complex (1:1 drug/dye) of LMT with bromocresol green (BCG) at pH 5.02±0.01 and extraction of the complex into dichloromethane followed by the measurement of the yellow ion-pair complex at 410 nm. In the second (method B), the drug-dye ion-pair complex was dissolved in ethanolic potassium hydroxide and the resulting base form of the dye was measured at 620 nm. Beer’s law was obeyed in the concentration range of 1.5-15 μg mL-1 and 0.5-5.0 μg mL-1 for method A and method B, respectively, and the = corresponding molar absorptivity values are 1.6932 x 104 and 3.748 x 104 L mol-1cm-1. The Sandell sensitivity values are 0.0151 and 0.0068 μg cm-2 for method A and method B, respectively. The stoichiometry of the ion-pair complex formed between the dug and dye (1:1) was determined by Job’s continuous variations method and the stability constant of the complex was also calculated. The proposed methods were applied successfully for the determination of drug in commercial tablets.
Viscometric investigations and molecular interactions of some derivatives of 5-substituted indole dihydropyrimidines in mixed organic solvents
Authors: Heda L. C. , Sharma Rashmi , Mosalpuri Sonraj R. , Chaudhari Pramod B. 
Published: February 2018

Colloid chemical behavior of indole dihydropyrimidines in non-aqueous solvent mixture benzene-methanol of varying composition has been investigated by viscometric measurements at 303K± 0.1. The viscosity of the system increases with the increase in concentration. The Trend Change Point (TCP) values have been determined by intersection of two straight lines, which are found to be dependent on the composition of solvent mixtures. The study confirms that the nature of synthesized compounds agglomerate formed below and above 50% benzene concentration is quite different. The viscometric data have been analyzed in terms of Einstein, Vand, Moulik and Jones-Dole equations. These well known equations have been successfully applied to explain the results of viscosity measurements and the viscometric parameters show that the behavior of compound changes in the proximity of 50% benzene concentration.
A pH optode based on thymol blue: application to determination of CO2 using flow injection analysis system
Authors: Sotomayor Maria Del Pilar Taboada , Raimundo Júnior Ivo Milton , Rohwedder Jarbas José Rodrigues , Oliveira Neto Graciliano 
Published: February 2018

An optode based on thymol blue (TB), an acid-based indicator, has been constructed and evaluated as a detector in FIA system for CO2 determination. The dye was chemically immobilised on the surface of a bifurcated glass optical fibre bundle, using silanisation in organic media. In FIA system, hydrogen carbonate or carbonate samples are injected in a buffer carrier solution, and then are mixed with phosphoric acid solution to generate CO2, which diffuses through a PTFE membrane, in order to be collected in an acceptor carrier fluid, pumped towards to detection cell, in which the optode was adapted. The proposed system presents two linear response ranges, from 1.0 x 10-3 to 1.0 x 10-2 mol l-1, and from 2.0 x 10-2 to 0.10 mol l-1. The sampling frequency was 11 sample h-1, with good repeatability (R.S.D < 4 %, n = 10). In flow conditions the optode lifetime was 170 h. The system was applied in the analysis of commercial mineral water and the results obtained in the hydrogen carbonate determination did not differ significantly from those obtained by potentiometry, at a confidence level of 95 %.
Distribuição de elementos tóxicos no estuário do rio Amazonas
Authors: Pereira Simone de Fátima Pinheiro , Pires Otílio Othon , Saraiva Augusto Fonseca , Oliveira Geiso Rafael , De Sousa Junior Pedro Moreira , Miranda Rafaella Galvão , E Silva Cleber Silva , Sales Reginaldo da Silva 
Published: February 2018

A presença de elementos não essenciais nas águas superficiais do rio Amazonas é uma preocupação global, o objetivo da pesquisa foi estudar a distribuição dos elementos As, Al, Mn, e Pb na água do estuário do rio Amazonas. As amostras foram coletadas em três regiões distintas: Canal Norte (AP), Canal Sul (PA) e rio Pará (PA) em três profundidades, com um total de 84 amostras. A espectrometria de emissão atômica com plasma indutivamente acoplado (ICPAES) foi utilizada para avaliar os teores de Al, Mn e Pb e a espectrofotometria de absorção atômica com geração de hidretos (HGAAS) foi usada para a análise do As. O As variou de <0,35 a 50,60 μg/L, o Al de <1,88 a 3347,70 μg/L, o Mn de 0,13 a 403,39 μg/L e Pb de <0,18 a 57,78 μg/L. Em média As (canal Sul), Al (todas as regiões), Mn (canal Norte e Sul) e Pb (canal Norte e Sul) se encontraram em valores acima do permitido pela legislação brasileira. Os elementos podem ter origem antrópica originária de atividade de mineração e industrial e origem natural proveniente de decomposição de rochas ígneas da bacia de drenagem do rio Amazonas que disponibilizam o elemento na forma ligada ao material particulado em suspensão.
Análise de iodato em sais de cozinha
Authors: De Freitas Gutto Raffyson Silva , Da Silva Junior Humberto , Pereira Francisco Régis da Silva , De Farias Robson Fernandes , Pereira Francisco Claudece 
Published: February 2018

Iodato pode ser reduzido em solução tampão B-R pH 2,0 por ação da hidroxilamina. Dependendo da concentração do agente redutor é possível gerar iodo molecular ou o complexo triiodeto. Iodo apresenta um conjunto de três picos de absorção, enquanto o complexo somente dois na região do ultravioleta. Utilizando excesso de hidroxilamina é possível monitorar o triiodeto em max. 352 nm e max. 288 nm. Empregando as melhores condições experimentais, curvas de calibração lineares entre 2,3x10-4 mol L-1 a 5,0x10-4 mol L-1 foram obtidas para a determinação de iodato. A metodologia foi aplicada em amostras de sais de cozinha de supermercados da cidade de Natal, RN.
Efeito da complexação de metais aos anti-inflamatórios na ação contra agentes oxidativos e radicais livres: ação do cetoprofeno
Authors: Manente Francine Alessandra , Rosolen de Almeida Mello Lucas , Kalil Omar Arafat Kdudsi , De Carvalho Cláudio Teodoro , Bannach Gilbert , Vellosa José Carlos Rebuglio 
Published: February 2018

Os radicais livres são espécies altamente reativas geradas nos organismos vivos com a finalidade de proteção. Porém, em algumas circunstâncias, estes são responsáveis pela ocorrência ou o agravo de danos teciduais. Muitos antiinflamatórios apresentam ação direta sobre radicais livres e espécies reativas não radicalares, o que contribui para suas ações contra a inflamação. O cetoprofeno é um antiinflamatório não esteroidal que gera radicais livres ao sofrer fotoirradiação e tem com isso um efeito hemolítico importante. A complexação de metais a diferentes fármacos tem sido utilizada como estratégia para melhorar a ação farmacológica de diferentes moléculas e reduzir seus efeitos colaterais. Neste trabalho são apresentados resultados do estudo de ação do cetoprofeno e seus complexos de cério e cobre sobre radicais livres e sobre eritrócitos. Observou-se que o cério intensifica as propriedades scavenger do cetoprofeno sobre radicais livres enquanto o cobre intensifica as ações sobre oxidantes não radicalares. O cobre ainda reduziu o efeito hemolítico apresentado pelo cetoprofeno e mantido pelo seu derivado de cério.
Humic substances from sediments of Lobos Pond (Argentina). Isolation, characterization and limnological implications
Authors: Choconi Roberto Gustavo , Ghini Alberto Antonio , Conzonno Victor Hugo , Cirelli Alicia Fernández 
Published: February 2018

Humic substances (HS) were isolated from the sediments of Lobos Pond (Argentina) using mild conditions to preserve their native structure. The HS (humic and fulvic acids) were characterized by means of elemental analysis and FTIR spectroscopy. Also a by-product obtained during fulvic acids (FA) fractionation (an amorphous white solid residue) was analyzed. Results revealed possible interactions between FA and inorganic-organic substances that may have implications referring to bioavailability. Other limnological implications, such as autochtonous origin of HS linked with the hydrology, and change of pH during stormy weather that affects HS interactions, are discussed.
Desenvolvimento de metodologia analítica baseada em eletrodo de carbono vítreo modificado com filme de bismuto: Aplicação em águas de chuva de regiões de Santa Catarina
Authors: Dos Santos Marcel Silveira , Bianchin Joyce Nunes , Spinelli Almir 
Published: February 2018

Neste estudo foi desenvolvida uma metodologia analítica para determinação de 2,4-dinitrofenol (2,4-DNP) em amostras de águas de chuva de regiões de Santa Catarina utilizando a voltametria de onda quadrada (VOQ) e de forma ex situ. O estudo envolveu a aplicabilidade de utilizar o eletrodo de carbono vítreo modificado com filme de bismuto. A formação do filme de bismuto foi otimizada por voltametria cíclica e em seguida, estudos de pH e eletrólito de suporte foram investigados para a redução do 2,4-DNP. Os parâmetros analíticos que afetam a sensibilidade da VOQ foram otimizados. Na sequência, as figuras analíticas de mérito foram obtidas: faixa linear de trabalho de 3,2 x 10-7 – 4,6 x 10-6 mol L-1, coeficiente de correlação de 0,996, RSD% = 17,5 (1,3 x 10-6 mol L-1, n = 6), 11,7 (2,5 x 10-6 mol L-1, n = 6) e 6,4 ( 4,5 x 10-6 mol L-1, n = 6), limite de detecção de 1,2 x 10-7 mol L-1. E, finalmente estudos de recuperação foram realizados para avaliar a exatidão da metodologia. Valores obtidos ficaram entre 84-112% (2,5 x 10-6 mol L-1) e 89 – 113% (4,5 x 10-6 mol L-1).
Eletrodo de pasta de carbono em minicavidade de contato sólido
Authors: Ferreira Antonio Aparecido Pupim , Ribeiro Sidney José Lima , Fugivara Cecílio Sadao , Caiut José Maurício Almeida , Sargentelli Vagner , Benedetti Assis Vicente 
Published: February 2018

Este trabalho descreve a preparação de eletrodo de pasta de carbono (EPC) em minicavidade de contato sólido e sua avaliação quando a pasta de carbono contém ou não partículas submicormétricas de SiO2(Eu3+ 2%) e SiO2(Eu3+ 2%)-lisina. Nestes estudos, medidas de voltametria cíclica e impedância eletroquímica foram realizadas em PBS (0,1 mol L-1 pH 7,4) contendo as espécies redox Fe(CN)6-3/-4. Os resultados de impedância foram interpretados baseados na reação de transferência de carga envolvendo as espécies Fe(CN)6-3/-4 e/ou oxigênio em frequências mais altas e, difusão das espécies eletroativas e características da pasta de carbono a baixas frequências. EPC-inicavidade é apropriado para eletroanálises usando pasta de carbono modificada.
Potencial alelopático e identificação de compostos secundários em extratos de calopogônio (Calopogonium mucunoides) utilizando eletroforese capilar
Authors: Dos Santos Sonia , De Moraes Maria de Lourdes Leite , Rezende Maria Olimpia de Oliveira , Sousa Filho Antonio Pedro da Silva 
Published: February 2018

Neste trabalho avaliou-se o potencial alelopático de extratos orgânicos obtidos a partir das folhas de Calopogonium mucunoides sobre a germinação de sementes de algumas plantas daninhas comumente encontradas em áreas de pastagens cultivadas da Amazônia brasileira, as quais causam grandes danos à produtividade: Cassia tora (mata-pasto), Mimosa pudica (malícia) e Cassia occidentalis (fedegoso). Compostos secundários foram identificados e quantificados nos extratos brutos utilizando eletroforese capilar. Após identificar e quantificar os compostos presentes nos extratos realizaram-se novos bioensaios com os padrões dos compostos identificados a fim de verificar se os mesmos poderiam atuar como inibidores na germinação das sementes das plantas daninhas em estudo. Calopogonium mucunoides apresentou potencial alelopático o qual variou com a espécie de planta daninha estudada. Os protocolos desenvolvidos utilizando eletroforese capilar se mostraram eficientes e bastante específicos, sendo possível a separação e identificação de 5 classes de compostos nos extratos brutos sem necessidade de “clean up” ou fracionamento dos mesmos, com análises rápidas (em menos de 20 minutos) e baixas quantidades de solventes utilizadas quando comparadas aos métodos tradicionais de análises. Vários dos compostos identificados apresentaram potencial de inibição de germinação nas sementes estudadas, sendo malícia a mais sensível, os bioensaios também indicaram certo efeito sinérgico ao utilizar a mistura de compostos.
OTIMIZAÇÃO DO PROCESSO FOTOCATALÍTICO HETEROGÊNEO PARA O TRATAMENTO DE PERCOLADO DE ATERRO SANITÁRIO
Authors: De Brito Núbia Natália , Archanjo Brota Giovani , Teixeira Pelegrini Ronaldo , Stipp Paterniani José Euclides 
Published: February 2018

The conventional methods used in the treatment of this residue lead to a discharge with intense coloration, high organic matter concentration, toxic metals and high toxicity. This work had as objective to study a system integrated for the remediation of the leachate originating from the sanitary landfill of Limeira-SP city The system consisted in a preliminary treatment by a system of slow sand filtration and the subsequent treatment through advanced oxidative processes, considering that the heterogeneous photocatalysis technique with TiO2/UV was experienced in remediation. The photocatalytic treatment was accomplished in a Pyrex glass reactor of approximately 1.7 L (100 mm of internal diameter, 145 mm of external diameter and total height of 300 mm). The experiments were carried out through water refrigeration and internal recirculation system of the leachate. To optimize the treatment process the best methodology it was evaluated to minimize the coloration of the leachate, one of the parameters of larger removal difficulty. The results were satisfactory with leachate coloration reduction in the order of: 66% in 180 min and 76% in 540 min of treatment with the heterogeneous fotocatálise, using 700 mg.L-1 of TiO2, 45°C temperature, 15 L.min-1 air flow and 400 Watts lamp.
DETERMINATION OF ORGANOCHLORINE PESTICIDE RESIDUES IN HUMAN MILK IN PIRACICABA, SP
Authors: Freguglia Rosana M.O. , Moura Andrade Graziela C. R. , Tornisielo Valdemar Luiz 
Published: February 2018

Worldwide, there is great concern with the issue of bioaccumulation of organochlorine compounds in human milk and their potential impact on health. Breastfeeding is recognized as essential for the proper development and protection of children’s health. In this study, we collected human milk samples from 40 donors in Piracicaba - SP, and analyzed to determine the levels of residues of organochlorine pesticides: hexachlorobenzene (HCB), lindane, heptachlor, aldrin, heptachlor epoxide, o,p’ DDE, a- endosulfan, p,p’ DDE, dieldrin, endrin, b-endosulfan, endosulfan sulfate, and methoxychlor. The analysis was performed by solid phase extraction (SPE) and quantification by gas chromatography using electron capture detector (ECD). Residues of organochlorine pesticides were detected in 65% of the donors evaluated.
OXYGENATED GLYCEROL DERIVATIVES AS AN ALTERNATIVE SOURCE OF ENERGY: A REVIEW
Authors: Cavalcante Kiany S. B. , Da Silva Mitchell G. S. , Sifrônio Francisco S. M. , Valois Renata R. S. , Maciel Adeilton P. , Souza Antonio G. , Silva Fernando C. 
Published: February 2018

Due to the excessive production of crude glycerol by the Brazilian biodiesel industries, the commercial interest for glycerol derivatives has widely increased. Therefore, several methodologies have been proposed for such purpose, combining the reuse of this abundant raw material with new applications. In such context, this review summarizes a number of works focused on oxygenated glycerol derivatives production, regarding the reactions mechanisms (etherification, acetalization, esterification, and fermentation) and the physicochemical chemical properties and application. Thus, this work aims to contribute to future studies in chemical modification of crude glycerol; hence most of the scientific publications have discussed additives yielded from pure glycerol.
GREEN AND SIMPLE UV-VISIBLE DIFFUSE REFLECTANCE AND TRANSMITTANCE METHODS FOR THE DETERMINATION OF NITROFURANTOIN IN PHARMACEUTICAL PREPARATIONS
Authors: Tubino M. , Bianchessi L. F. , Palumbo M. , Vila M. M.D.C. 
Published: February 2018

Two quantitative analytical methods for the determination of nitrofurantoin in pharmaceutical preparations in the visible-ultraviolet range of the spectrum are reported. One of them uses the diffuse reflectance technique and the other transmittance measurements in aqueous solution. Both procedures are very simple to be performed and also present green characteristics as only polyethylene glycol and water are used as solvents. Commercial pharmaceutical preparations of the drug were analyzed using the proposed methods. The results were compared with those obtained when the HPLC procedure recommended by the USP was applied. Statistical comparison using the paired Student’s t test and the Snedecor’s F test showed good agreement between all the methods.
A interferência das atividades antrópicas na qualidade da água em reservatório de abastecimento urbano. Estudo de caso: represa Dr. João Penido (Juiz de Fora, MG)
Authors: Bucci Maria Magaly Heidenreich Silva , De Oliveira Luiz Fernando Cappa 
Published: February 2018

Dr. João Penido dam is the main reservoir for water supply of Juiz de Fora (MG). The forms of land use and occupation have produced negative impacts on the aquatic ecosystem. The general objective of this study was to assess the anthropogenic impact on water quality of the watershed. To this was done to characterize the quality of its waters and the parameters measured were compared with CONAMA Resolution 357/2005. It was also calculated the Water Quality Index (WQI) and the Trophic State Index (TSI). The monitoring tool has proved essential in actions involving preservation of the watershed.
Spectrophotometric determination of furosemide in pharmaceutical formulations – A didactic approach, from practice to theory
Authors: Da Silva Neto Adalberto Alves , Pacheco Wagner Felippe , Semaan Felipe Silva 
Published: February 2018

Spectrofluorimetric determination of furosemide in pharmaceutical – a didactical approach, from theory to practice. The purpose of this paper is to present a complete possible application of simple strategies to teach basic concepts of molecular spectrofluorimetry. An ordinary anti-hypertensive drug was chosen in order to demonstrate many theoretical and practical aspects of spectrofluorimetric determinations in an accurate, precise, and inexpensive analytical lab practice. Historical aspects and fundamentals, and their contextualization for students, are also presented, being some experiments described using cheap samples.
Evaluation of pollution level caused by domestic effluent in the Poty river – Teresina PI - Brazil
Authors: Damasceno Izabele Folha , Leal Vivane Lopes , Coelho Ronaldo Cunha , De Moura Carla Verônica Rodoarte , De Moura Edmilson Miranda 
Published: February 2018

This article reports on the level of contamination of effluents, sediments and water in the Poty River, within the city of Teresina. The samples were collected in the months of September 2009, December 2009 and March 2010. The results of some physico-chemical parameters investigated, as well as the concentrations of lead, copper and nickel found in the river water samples showed that the body of water in the Poty River is unsuitable for use in various activities. These activities include direct recreational usage and primary irrigation of vegetables that are eaten raw as well as fruits that are eaten without removing films, among others.
Water dams for use in drip irrigation in the city of penedo / Al: physico-chemical and biological quality
Authors: Oliveira Silva Orlando , Dos Santos Elane Cristina Lourenço , Lopez Ana Maria Queijeiro 
Published: February 2018

In areas where rainfall is irregular or not reaches the required the supply for cane cultivation, irrigation is essential. The introduction of drip irrigation (with surface or underground micro-sprinklers), has been one of the factors that contributed to the increase in sugar and alcohol productivity in the region of Alagoas. This study outlined a profile of physico-chemical and biological features of impounded water dam “Salvador Lyra”, in the city of Penedo-AL, used to irrigate crops in a sugarcane mill, with the purpose to know the causes of obstructions detected in the issuing of the drip irrigation system, and to propose consistent control measures. During the period of one year, samples from three points along the dam were subjected to microbiological analysis and pH, hardness, electrical conductivity, concentraction of total dissolved solids, dissolved oxygen and Fe2. With respect to microbiological analysis, it was isolated from the neutral waters an aerobic bacteria producing siderophore iron chelators, classified as the species Pseudomonas aeruginosa (Schroeter 1872) Migula (1900), and the results of physico-chemical analysis showed the prevalence of with a high risk of biological clogging (> 50,000 cells / mL).
Infeksi protozoa berflagela pada kura-kura indian star
Authors: Mihardi Arief Purwo , Wulandari Eka Dewi , Hage George Marthienz Do 
Published: February 2018

Protozoa biasa ditemukan pada saluran pencernaan hewan reptil. Jumlah protozoa yang tinggi dapat menimbulkan masalah kesehatan pada hewan reptil seperti kura-kura. Pasien jenis kura-kura jantan dengan ras indian star datang dengan keluahan menurunnya nafsu makan serta feses yang encer dan berwarna putih. Penetapan diagnosa diperoleh dari hasil pemeriksaan fisik dan pemeriksaan laboratorium. Pemeriksaan laboratorium yang dilakukan meliputi pengamatan pada sampel feses secara natif, pengapungan dengan larutan gula jenuh serta pewarnaan sampel feses. Hasil pemeriksaan laboratorium menunjukkan bahwa kura-kura terinfeksi protozoa berflagela. Berdasarkan morfologi protozoa yang diamati, diduga termasuk ke dalam genus trichomonad. Namun perlu pemeriksaan lebih lanjut untuk memastikan jenis protozoa, karena sulit bila hanya berdasarkan pemeriksaan morfologi secara sekilas.