Spectrophotometric determination of total alkaloids in some Iranian medicinal plants

A simple spectrophotometric method based on the reaction with Bromocresol Green [BCG] has been developed for determination of total alkaloids in medicinal plants. A yellow complex forms and is easily extractable by chloroform at pH 4.7. The absorbance of the complex obeys Bear's law over the concentration range of 4-13 micro g atropine per mL of choloroform. This procedure can be carried out in the presence of other compounds without interference

[Spectrophotometric determination of enalapril maleate by bi-complex formation with bromocresol green]

We developed a new, simple, sensitive method for determination Enalapril Maleate [EM] by formation yellow complex between Enalapril Maleate and Bromocresol green [BCG]. The complex absorption maximum was at lambda max = 417 nm. The optimum conditions for complex formation were the buffer volume of HC1+KC1 0.2M for each [2-3] ml and 5 ml of Bromocresol green 1.10[-3] M which was enough for complete complex formation when the concentration of Enalapril Maleate was 10 mg/L. The linear relationship between the absorbance and the concentration of Enalapril Maleate was in the range of 5-35 mg/L, molecular molar absorsivity was 25125 L.mol[-1].cm[-1], the molar ratio [Indicator, drug] was [1:1]. This new method had offered a determination of Enalapril Maleate with a high accuracy and an authenticity for the analytical results. The minimal concentration could determine was 1 mg/L with relative standard deviation does not exceed 2.86%. We determined Enalapril Maleate by this method either in its raw material or pharmaceutical form without any interference with auxiliary excepients or Hydrochlorothiazide in its present case

Caracterización cromatográfica de subfracciones antimicrobianas del agua del volcán Copahue (Neuquén, Argentina) / Chromatographic characterization of antimicrobial subfractions from the Copahue Volcano water (Neuquén, Argentine)

Eluciones susivas con distintos solventes del carbón activado, usado como adsorbente del Agua del Volcán Copahue (AVC) permitieron confirmar de nuevo que la extrema acidez de las muestras naturales obtenidas de la vertiente, no es la principal causa del efecto antibiótico, en contacto de breve período en las valoraciones biológicas. Los ensayos cromatográficos, aplicando reactivos microquímicos específicos y modificados, permitieron la detección de los principales compuestos acídicos, a partir de los eluidos residuales sucesivos, respectivamente obtenidos con acetato de etilo y con éter sulfúrico. Con acetato de metanólicos. Se sugiere que el AVC contiene, además de los productos sulfurosos bioactivos, otros elementos que actuarían en forma aditiva o sinérgica en los efectos biocidas y regenerativos, importantes en la crenoterapia

Determinaçäo de albumina humana em soros normais: comparaçäo de três métodos / Determinantion of human albumin in normal sera: comparison of 3 methods

A concentraçäo de albumina em soros de indivíduos normais foi determinada através dos métodos verde de bromocresol (VBC), púrpura de bromocresol (PBC) e imunoturbidimetria (I). A precisäo (Cv) destes métodos, investigada em "pool" de soros normais, foi de 3,6% para o imunoensaio e de 2,8% e 2,5% para o VBC e PBC, respectivamente. Estudos comparativos mostraram que os valores de albumina obtidos pelos métodos colorimétricos foram sistemática e significativamente mais elevados que os determinados por imunoturbidimetria. A PBC proporcionou valores de albumina mais próximos daqueles conferidos pela imunoturbidimetria, corroborando as evidências já apontadas na literatura a cerca da maior especificidade da reaçäo PBC-albumina