Sample records for crystal violet
from WorldWideScience.org

Sample records 1 - 7 shown.



1

Estudo da sorção do corante catiônico violeta cristal por espuma de poliuretano em meio aquoso contendo dodecilsulfato de sódio/ Sorption of crystal violet by polyurethane foam from aqueous medium containing sodium dodecylsulfate

Mori, Mariana; Cassella, Ricardo J.
2009-01-01

Resumo em inglês This work presents a detailed study about the sorption of crystal violet (CV) cationic dye onto polyether type polyurethane foam (PUF). The sorption process was based on the formation of an ionic-pair between cationic dye and dodecylsulfate anion (SDS), which presented high affinity by PUF. Set-up employed in the study was built up by adjusting a 200 mg cylinder of PUF to the arm of an overhead stirrer. The system was characterized in relation to equilibrium and kinetic a (mais) spects and it was modeled by employing Langmuir and Freundlich isotherms. Obtained results showed that the ratio between SDS and MB concentrations played an important role on the sorption process. According to results found it was possible to retain up to 3.4 mg of dye from 200 mL of a 5.0 x 10-5 mol L-1 CV solution containing 1.25 x 10-4 mol L-1 SDS, which represented a removal efficiency of around 92%.

Scientific Electronic Library Online (Portuguese)

2

Identificação e quantificação do cristal violeta em aguardentes de mandioca (tiquira)/ Identification and characterization of crystal violet in cassava spirits (tiquira)

Santos, Geraldino da Silva; Marques, Edmar Pereira; Silva, Hildo Antônio dos Santos; Bezerra, Cícero Wellington Brito; Marques, Aldaléa Brandes
2005-08-01

Resumo em inglês Tiquira is a traditional homemade alcoholic distillate produced in the Maranhão State (Brazil), gotten from cassava (Manihot esculenta, Crantz.). It can be normally found on street markets. Due to the addition of tangerine leaves, the original tiquira has a bluish color. Samples of this beverage were acquired in the local trade and analyzed from the spectroanalytical point of view. The results indicated that these drinks had been adulterated by the addition of crystal vi (mais) olet, a potencialy hazardous compound. The identification and quantification of crystal violet in 10 spiked samples was accomplished by UV-Vis spectrophotometry through the standard addition method. In order to verify the efficiency of the proposed method, experiments on the quantification and recovery were carried out and the results indicated a content of crystal violet in the 10-6 to 10-7 mol L-1 range.

Scientific Electronic Library Online (Portuguese)

3

Preparação e caracterização de substratos SERS ativos: um estudo da adsorção do cristal violeta sobre nanopartículas de prata/ Preparation and characterization of SERS-active substrates: a study of the crystal violet adsorption on silver nanoparticles

Santana, Henrique de; Zaia, Dimas A. M.; Corio, Paola; El Haber, Fady; Louarn, Guy
2006-04-01

Resumo em inglês The structural characterization of molecules used in the sterilization of blood for transfusions, such as crystal violet (CV), is relevant for understanding the action of these prophylactic drugs. The characterization is feasible by surface enhanced resonance Raman spectroscopy (SERRS) of CV in solution or on surfaces. The limit of detection of CV by SERRS, in the presence of colloidal particles, using 514.5 nm as excitation radiation, was found to be around 1 ppb. The ch (mais) aracterization of CV was also made by SERS, by using different active-particles-containing substrates, proving the versatility of this technique for the study of such structures. The results suggest that the controlled production of highly efficient SERS-active substrates may allow qualitative and quantitative analysis, with high sensitivity, with potential applications in medical and environmental fields.

Scientific Electronic Library Online (Portuguese)

4

Caracterização de biótipos de Staphylococcus aureus isolados de mastite bovina/ Biotyping of Staphylococcus aureus strains isolated from bovine mastitis

Brito, M.A.V.P.; Brito, J.R.F.; Cordeiro, F.M.; Costa, W.A.; Fortes, T.O.
2000-10-01

Resumo em português Duzentos e dezoito amostras de Staphylococcus aureus, isoladas de infecção intramamária de vacas de 44 rebanhos leiteiros, foram classificadas em biótipos de acordo com os testes de produção de estafiloquinase (K), beta-hemolisina (beta ), coagulação do plasma bovino (Pl) e crescimento na presença de cristal violeta (CV). As amostras foram distribuídas em 10 biótipos e 63 delas foram classificadas nas ecovariedades bovina (35), ovina (17), aviária (10) e human (mais) a (1) e 155 não apresentaram características específicas de hospedeiro. Estas últimas podem ser isoladas de homem, cabra, coelho, suíno, alimentos e de mastite bovina. O biótipo 1, encontrado com maior freqüência (37,2%), apresentou o padrão K (-), beta (+), Pl (-) e CV (azul). Em sete rebanhos nos quais se examinaram 10 ou mais amostras, verificou-se que, apesar da ocorrência simultânea de mais de um biótipo por rebanho, houve predominância de um sobre os demais. Resumo em inglês Two hundred and eighteen strains of Staphylococcus aureus isolated from bovine intramammary infections, obtained from 44 different dairy herds, were classified in biotypes based on staphylokinase (K) and beta-haemolysin (beta ) production, bovine plasma coagulation (Pl) and growth on crystal violet agar (CV). The strains were assigned to 10 different types, with 63 in the bovine (35), ovine (17), poultry (10) and human (1) ecovars and 155 in non-host specific biotypes. Th (mais) e latter can be isolated from man, goat, rabbit, pig, food, and bovine mastitis. The biotype 1, with reaction pattern K (-), beta (+), Pl (-) and CV (blue), was the most frequently found (37,2%). From seven herds ten or more strains were examined. It was found that in spite of the presence of different biotypes per herd, there was always one prevalent biotype.

Scientific Electronic Library Online (Portuguese)

5

Comparação de métodos de isolamento de bactérias NAD-dependentes do trato respiratório superior de suínos sadios/ Methods to isolate NAD-dependent bacteria from the upper respiratory tract of health pigs

Kich, J.D.; Piffer, I.A.; Barcellos, D.E.S.N.; Guidoni, A.L.; Klein, C.S.; Fávero, M.B.B.; Vizotto, R.
2000-02-01

Resumo em português Secreções nasais, tonsilares e tecido tonsilar foram coletados de 67 leitões de 9 a 15 semanas de idade, provenientes de três rebanhos positivos para Actinobacillus pleuropneumoniae (App), e de 50 leitões provenientes de dois rebanhos negativos. Foram classificados como positivos aqueles rebanhos com isolamento prévio de sorotipos 3, 5 e 7 e rebanhos negativos aqueles submetidos a controle veterinário, sem notificação de sintomas clínicos, lesões de pleuropneum (mais) onia suína e sem isolamento do agente. O material coletado foi submetido a três diferentes métodos de cultivo: 1- semeadura direta em meio de cultivo sólido seletivo; 2- diluição em caldo seletivo seguido de subsemeadura em meio de cultivo sólido seletivo; 3- diluição em caldo seletivo seguido de subsemeadura em ágar sangue. Entre as amostras NAD-dependentes recuperadas 86 foram classificadas como App, 13 como grupo minor e 21 como grupo taxon (C, D, E e F). Dos rebanhos positivos foram recuperadas quatro amostras de App (sorotipos 3, 7 e 12) e 51 não sorotipificáveis. Dos rebanhos negativos foram recuperadas 31 amostras de App não sorotipificáveis, indicando que o App faz parte da flora normal do trato respiratório superior dos suínos. O melhor método de isolamento de amostras NAD-dependentes de leitões portadores foi da biópsia de tecido tonsilar semeado diretamente em meio sólido seletivo (PPLO ágar adicionado de 2mi g de cristal violeta, 10mi g NAD, 1mi g de lincomicina, 1,4mi g de bacitracina por ml). Resumo em inglês Nasal and tonsil secretions and tonsil tissue were collected from 67 piglets (9-to-15 weeks old) from three positive herds and from 50 piglets from two negative herds. Positive herds were those in which an Actinobacillus pleuropneumoniae (App) strain of serotype 3, 5 or 7 was isolated and negative ones those in which there was no notification of clinical symptoms or lesions of swine pleuropneumoniae, no App isolation and the herd was under veterinarian control. The collec (mais) ted material was submitted to three different bacterial culture methods: 1- direct streak on solid selective medium, 2- dilution in selective broth followed by subculture in solid selective medium, and 3- dilution in selective broth medium followed by subculture in blood agar. Among the NAD-dependent strains recovered 86 were App, 13 belonged to the minor group and 21 to the Taxon group (C, D, E e F). From the positive herds four serotyped strains of App (sorotypes 3, 7 and 12) and 51 nonsorotipable strains were recovered. From the negative herds 31 nonsorotipable strains of App were recovered, indicating that App is a resident in the upper respiratory tract of pigs. The best method for recovering NAD-dependent strains from carrier piglets was achieved by direct culturing of tonsil tissue in solid selective medium (PPLO agar containing 2mu g of crystal violet, 10mu g of NAD, 1mu g of lincomycin, 1,4mu g of bacitracin per ml).

Scientific Electronic Library Online (Portuguese)

6

Caracterização de quartzo para obtenção de suas variedades gemológicas por irradiação gama e/ou tratamento térmico/ Quartz characterization to obtain its gemological varieties by means of gamma irradiation and/or heat treatment

Drummond, Ney Friedemann; Mendes, Júlio César; Lameiras, Fernando Soares
2010-09-01

Resumo em português Apesar da grande produção de quartzo em Minas Gerais, pouco é conhecido sobre a influência do ambiente geológico na geração das variedades coloridas através de tratamento. Sabe-se que a irradiação gama, seguida ou não de aquecimento, conduz à formação de cores, tais como acontece com a ametista, prasiolita, green gold, beer, cognac, whisky e champagne. Amostras de ambientes hidrotermal e pegmatítico foram submetidas a ensaios por espectroscopia de absorçã (mais) o na região do infravermelho por transformada de Fourier (FTIR) e irradiação gama seguida ou não de tratamento térmico. Os espectros obtidos por FTIR mostram bandas correlacionadas a elementos dopantes, os quais indicam o potencial da amostra pelo aparecimento de cor e permitem determinar as doses que serão aplicadas na irradiação gama e as temperaturas que serão utilizadas no tratamento térmico. Os resultados dos ensaios mostraram que quartzo de ambiente hidrotermal com valores anômalos de ferro, com banda FTIR a 3.585cm-1, fator fa > 3,3 e área entre 400 e 600u.a*cm-1, poderá desenvolver a cor violeta; quartzo com anomalias de lítio na estrutura do cristal derivado de núcleo de pegmatitos altamente diferenciados ricos em minerais de lítio apresentando banda FTIR a 3.485cm-1, fator fLi > 2,0 e irradiado com doses de 65 a 400kGy pode desenvolver cores amarelo-esverdeadas a acastanhadas. É possível concluir que ametista e prasiolita são produzidas de quartzo de ambiente hidrotermal, enquanto variedades gemológicas raras, tais como green gold, beer, cognac, whisky e champagne são produzidas de quartzo de pegmatitos altamente diferenciados, que contêm minerais de lítio. Resumo em inglês Despite the large production of quartz in Minas Gerais, little is known about the geological environment influence on the generation of colored varieties by treatment. It is known that gamma irradiation, followed or not by heating, leads to the generation of colors such as amethyst, prasiolite, green gold, beer, cognac, whisky and champagne. Samples from hydrothermal and pegmatitic environments were subjected to tests by absorption spectrometry in the infrared region with (mais) the FOURIER transform (FTIR), gamma irradiation and heat treatment. The obtained FTIR-spectra show characteristic bands correlated to doping-elements, which indicates the color appearance potential of the sample, and allow to quantify the applied doses of gamma irradiation and the temperatures in heat treatment. The results of the tests indicate that quartz from a hydrothermal environment with anomalous levels of iron, with FTIR-band of 3585cm-1, factor fa > 3.3 and area between 400 a 600u.a*cm-1, may develop a violet color; quartz with lithium anomaly in the crystal structure derived from nuclei of highly differentiated pegmatites rich in lithium minerals, presenting FTIR-band of 3485cm-1, fLi factor > 2 and irradiated with doses of 65 to 400kGy, may develop yellow-green and brown colors. It is possible to conclude that amethyst and prasiolite are produced from quartz from a hydrothermal environment, while rare varieties such as green gold, beer, cognac, whisky and champagne are generated from quartz from highly differentiated pegmatites that bear Li-minerals.

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7

Avaliação da citotoxicidade de elásticos ortodônticos intermaxilares/ Citotoxicity evaluation of intermaxillary orthodontic elastics

Pithon, M.M.; Santos, R.L.; Oliveira, M.V.; Mendes, G.S.; Romanos, M.T.V.
2009-04-01

Resumo em português O objetivo do presente trabalho é avaliar a citotoxicidade de quatro diferentes marcas comerciais de elásticos inter-maxilares intra-orais. Foram avaliados elásticos da American Orthodontics (Grupo 1), 3M Unitek (Grupo 2), Morelli (Grupo3) e Uniden (Grupo 4). Os elásticos foram previamente esterilizados em luz ultravioleta e colocados em placas de Petri, as quais continham cultura de células HEp-2., Após 24 h, as monocamadas de células foram coradas e, em seguida, (mais) realizada uma avaliação dos halos de difusão e de lise celular. Os resultados demonstraram a ausência de citotoxicidade nos elásticos da marca American Orthodontic e 3M Unitek e alta citotoxicidade nos elásticos das marcas Morelli e Uniden. Com base nos resultados encontrados, através da metodologia utilizada, conclui-se que os elásticos da marca Morelli e Uniden são citotóxicos. Resumo em inglês The objective of the present study is to evaluate the cytotoxicity of four different commercial brands of intermaxillary orthodontic elastics. Four commercial brands of elastics were evaluated: American Orthodontics (Group1), 3M Unitek (Group 2), Morelli (Group 3) and Uniden (Group 4).The elastics were previously sterilized with Ultraviolet light and placed in Petri dish which tissue culture HEp-2. After 24 hr, the monolayers of cells were ruddystained with violet crystal (mais) and followed by an evaluation of the diffusion halo and cells lyses. The results demonstrated no cytotoxity for the American Orthodontic and the 3M Unitek elastics, and hight cytotoxicity for Morelli and Uniden elastics. Based on the results found, supported by the methodology utilized, it was concluded that the Morelli and Uniden elastics present high cytotoxicity.

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