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1.
IET Nanobiotechnol ; 12(7): 888-894, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30247126

RESUMO

CaO nanoparticles have been prepared using CaCl2 and aqueous extract of broccoli as a precursor and reducing agent, respectively. Different volumes of the aqueous broccoli extract were utilised to obtain Ca(OH)2 and subsequent calcination gave CaO nanoparticles. The synthesised CaO was confirmed by powder X-ray diffraction (XRD). The morphology was studied using transmittance electron microscopy (TEM), and the surface composition of Ca(OH)2 was explored using Fourier transform infrared spectroscopy. The major functional groups present in the capping material responsible for the reduction of the metal salt and the surface passivation of Ca(OH)2 were identified. The XRD pattern revealed cubic phase for all the CaO nanoparticles, and the crystallite size was estimated using Scherrer's equation showed a variation which is dependent on the volume of the extract used. TEM analysis showed different shapes, while the selected area electron diffraction (SAED) results confirmed the crystallinity of the nanoparticles. Thermogravimetric analysis of Ca(OH)2 showed the decomposition product to be CaO. Sample C3, which has the smallest particle size, was used as a catalyst for the degradation of bromocresol green via photo irradiation with ultraviolet light and the result revealed a degradation efficiency of 60.1%.


Assuntos
Brassica/química , Verde de Bromocresol/análise , Compostos de Cálcio/química , Nanopartículas/química , Óxidos/química , Extratos Vegetais/química , Verde de Bromocresol/química , Verde de Bromocresol/metabolismo , Recuperação e Remediação Ambiental , Química Verde/métodos , Fotólise , Extratos Vegetais/metabolismo
2.
Scand J Clin Lab Invest ; 77(6): 472-476, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28613959

RESUMO

Correct reference intervals are an important part of test results. As establishing own reference intervals is a very expensive task, the NORIP reference intervals are often transferred for use in Nordic laboratories. The NORIP reference interval on P-Albumin was here compared to current results for laboratories using the bromocresol purple (BCP) method for P-Albumin. External quality control reports were used to investigate the change in levels between the BCP and BCG methods on P-Albumin. An algorithm was built for extracting and isolating the laboratory's healthy subject population. The algorithm was used to extract test results from the laboratory information system. Parametric and non-parametric statistical methods were used to evaluate the P-Albumin test result populations. The indirect method used here clearly shows that the NORIP reference intervals for P-Albumin are not fit for the current bromocresol purple methods. The method was also used to suggest new reference interval limits.


Assuntos
Púrpura de Bromocresol/análise , Albumina Sérica/análise , Adolescente , Adulto , Verde de Bromocresol/análise , Intervalos de Confiança , Feminino , Humanos , Masculino , Valores de Referência , Adulto Jovem
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 163: 108-14, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27038582

RESUMO

In the present work, levocetirizine dihydrochloride (LEV) was found to interact with bromocresol green (BCG) via ion-pair formation. UV-vis and FTIR spectroscopy were used to validate the data obtained from quantum mechanical calculations (QMC). The electrostatic potential maps show that the reaction is preferred through the interaction of the sulfonic acid group of BCG and the quaternary ammonium group of LEV. The optimized geometry of the product shows that there are six different intermolecular hydrogen bonds between the studied molecules resulting from the ionic attraction between the oppositely charged groups. The UV-vis spectra suggest the formation of an ion-pair. This finding is contradicting with the previous charge-transfer hypothesis.


Assuntos
Verde de Bromocresol/análise , Cetirizina/análise , Modelos Moleculares , Teoria Quântica , Verde de Bromocresol/química , Cetirizina/química , Elétrons , Ligação de Hidrogênio , Íons , Conformação Molecular , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
4.
Ann Clin Biochem ; 50(Pt 6): 576-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23897106

RESUMO

BACKGROUND: The controlling nutritional status (CONUT) score (CS), a simple score for assessing nutritional status, is calculated using laboratory data, including serum albumin concentration. Although dye-binding assays such as the bromocresol green (BCG) and modified bromocresol purple (mBCP) methods are widely used for albumin measurement, acute-phase proteins interfere with the BCG method. OBJECTIVE: We aimed to determine whether the choice of albumin assay affects assessment of nutritional status using CONUT scores (CSs). DESIGN: We measured serum albumin concentrations by the BCG (ALBBCG) and mBCP (ALBmBCP) methods in 44 malnourished inpatients, 27 of whom underwent nutritional intervention, and compared them to 30 age-matched healthy volunteers. In treated patients, CSs were calculated by ALBBCG (CS-BCG) and ALBmBCP (CS-mBCP). RESULTS: C-reactive protein (CRP) concentrations were positively correlated with the difference between ALBBCG and ALBmBCP in malnourished inpatients (r = 0.59, p < 0.001). CS-BCG was always lower than CS-mBCP (lower CS indicates superior nutritional status) in treated patients with persistently high CRP levels. However, in patients whose CRP decreased gradually, this difference diminished over the clinical course. CS-BCG and CS-mBCP were similar throughout their courses in patients with normal CRP concentrations. Adding haptoglobin to the human albumin solutions increased ALBBCG in a dose-dependent manner. CONCLUSIONS: The choice of albumin assay affected the assessment of nutritional status using CSs in patients with inflammation. We recommend that the modified BCP assay be used to assess nutritional status, particularly in patients with inflammation.


Assuntos
Análise Química do Sangue/métodos , Verde de Bromocresol , Púrpura de Bromocresol , Desnutrição/sangue , Desnutrição/fisiopatologia , Estado Nutricional , Albumina Sérica/análise , Idoso , Artefatos , Verde de Bromocresol/análise , Verde de Bromocresol/química , Púrpura de Bromocresol/análise , Púrpura de Bromocresol/química , Feminino , Haptoglobinas/farmacologia , Humanos , Inflamação/complicações , Masculino , Desnutrição/complicações , Pessoa de Meia-Idade
5.
Folia Microbiol (Praha) ; 53(6): 527-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19381479

RESUMO

We describe here a newly developed method for a contact-free optical pH measurement in yeast suspensions supplemented with glucose, and containing the pH sensitive triphenylmethane dye bromocresol green. It is suitable for performing the acidification power test (based on measuring the rate of pH drop of yeast suspension caused by active extrusion of acidity from cells after glucose addition) used for assessing yeast vitality in fermentation industries. Using this methodology we monitored the pH in yeast suspensions in the course of acidification in the pH range of 3.5-5.3. Optical pH measurement allows simultaneous testing of several samples, minimizes the sample volume, simplifies sample handling and reduces the hands-on time in sample processing.


Assuntos
Verde de Bromocresol/análise , Colorimetria/métodos , Meios de Cultivo Condicionados/química , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/análise , Micologia/métodos , Nefelometria e Turbidimetria/métodos , Leveduras/metabolismo , Colorimetria/instrumentação , Fermentação , Glucose/metabolismo , Micologia/instrumentação , Nefelometria e Turbidimetria/instrumentação
6.
Anal Bioanal Chem ; 388(5-6): 1303-10, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17522849

RESUMO

Multipumping (MPFS) and multicommuted (MCFS) flow systems relying on pulsed and laminar flows were critically compared. The mixing conditions and dispersion associated with both systems were evaluated by simulating the sample with bromocresol green. The molybdenum blue method for phosphate determination in soil extracts was also implemented in both flow systems. Furthermore, laser-induced fluorescence (LIF) was applied to visualize the dispersing sample; rhodamine B was used as the fluorescent species. The pulsed flow enhanced the mixing of the solutions involved, thus reducing reagent consumption (48 and 96 microl for MPFS and MCFS), and improving sampling rate (67 and 144 h(-1) for MCFS and MPFS). For phosphate determination, results obtained with both systems were precise (r.s.d. < 0.5%; n = 10) and accurate. Analyses of the absorbance vs time/space LIF plots revealed that exploitation of pulsed flow led to a pronounced radial dispersion and to a limited axial dispersion, typical aspects of turbulent flows.


Assuntos
Técnicas de Química Analítica/métodos , Verde de Bromocresol/análise , Calibragem , Corantes Fluorescentes/química , Lasers , Modelos Químicos , Modelos Teóricos , Molibdênio/análise , Fosfatos/análise , Fosfatos/química , Reprodutibilidade dos Testes , Soluções , Espectrometria de Fluorescência , Fatores de Tempo
7.
J AOAC Int ; 89(4): 966-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16915831

RESUMO

Simple and reproducible spectrophotometric methods have been developed for determination of sertraline, fluoxetine, and venlafaxine in pharmaceutical preparations. The methods are based on the reactions between the studied drug substances and ion-pair agents (bromothymol blue, bromocresol green, or bromophenol blue) to produce yellow-colored ion-pair complexes in acidic buffers. After extracting in chloroform, the ion-pair complexes are spectrophotometrically determined at the optimum wavelength. Optimizations of the reaction conditions were carried out. Beer's law was obeyed within the concentration range from 1 to 15 microg/mL. The molar absorptivity, Sandell sensitivity, and detection and quantification limits were also determined. The developed methods were applied successfully for the determination of these drugs in some available commercial preparations. The results were compared statistically with those obtained from reported high-performance liquid chromatography methods.


Assuntos
Antidepressivos/análise , Antidepressivos/farmacologia , Química Farmacêutica/métodos , Cicloexanóis/análise , Fluoxetina/análise , Sertralina/análise , Espectrofotometria/métodos , Verde de Bromocresol/análise , Azul de Bromofenol/análise , Azul de Bromotimol/análise , Concentração de Íons de Hidrogênio , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cloridrato de Venlafaxina
8.
Toxicol Lett ; 84(1): 13-22, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8597173

RESUMO

Changes in hepatic paracellular permeability were investigated during the development of cholephilic dye-induced cholestasis in rats. For this purpose, four dyes with different cholestatic potency (phenol red, sulfobromophthalein, bromcresol green and rose bengal) were infused at a high, potentially damaging dose (280 nmol/min per 100 g body wt., i.v.), and changes in paracellular permeability were continuously monitored by measuring the access into bile of the permeability probe -14C-sucrose. The cholestatic potency of the different dyes was: rose bengal > bromcresol green > sulfobromophthalein > phenol red. All dyes increased [14C]sucrose bile-to-plasma ratio, producing a displacement towards curves of higher permeability. The capability of the dyes to increase biliary permeability followed the same order as their respective cholestatic potencies. The possible implications of the present results for cholephilic dye-induced cholestasis are discussed.


Assuntos
Sistema Biliar/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Colestase/induzido quimicamente , Corantes/toxicidade , Animais , Bile/química , Bile/fisiologia , Sistema Biliar/metabolismo , Verde de Bromocresol/administração & dosagem , Verde de Bromocresol/análise , Verde de Bromocresol/toxicidade , Colestase/metabolismo , Corantes/administração & dosagem , Injeções Intravenosas , Junções Intercelulares/metabolismo , Testes de Função Hepática , Masculino , Fenolsulfonaftaleína/administração & dosagem , Fenolsulfonaftaleína/análise , Fenolsulfonaftaleína/toxicidade , Ratos , Ratos Wistar , Rosa Bengala/administração & dosagem , Rosa Bengala/análise , Rosa Bengala/toxicidade , Sacarose/metabolismo , Sulfobromoftaleína/administração & dosagem , Sulfobromoftaleína/análise , Sulfobromoftaleína/toxicidade , Fatores de Tempo
9.
J Pharm Sci ; 75(4): 416-20, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3723365

RESUMO

An ion-pair extraction technique is described for separating methenamine, a urinary tract antibacterial agent, from formaldehyde in human urine samples. Separation conditions are developed from extraction constants for the methenamine-bromocresol green ion-pair. The technique involves adsorption of the ion-pair onto a silica cartridge and elution with methylene chloride:1-pentanol (95:5). Methenamine is freed from the ion-pair by the addition of excess tetrabutylammonium iodide and converted to formaldehyde (determined spectrophotometrically) by reaction with ammonia and acetylacetone. Linear standard plots were obtained from urine containing methenamine which was diluted to 10-160 micrograms/mL. The lower limit of detection was 6 micrograms/mL of methenamine. Absolute recovery from urine was greater than or equal to 94.5%. The precision (CV) of detection of methenamine in the presence of formaldehyde was less than 2%, and less than or equal to 4.5% for the detection of formaldehyde in the presence of methenamine. No interferences were noted. The applicability of the method was demonstrated by analysis of human urine levels of both methenamine and formaldehyde following oral administration of a methenamine salt to a volunteer.


Assuntos
Metenamina/urina , Adulto , Disponibilidade Biológica , Verde de Bromocresol/análise , Fenômenos Químicos , Química , Formaldeído/urina , Humanos , Troca Iônica , Masculino
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