A sensitive three-signal assay for the determination of PFOS based on the interaction with Nile blue A

A kinetic spectrophotometric method for determination of lisinopril in pharmaceuticals has been developed. The method is based on activator action of lisinopril on Cu(II) ions catalysing the oxidation of nile blue A with hydrogen peroxide in borate buffer (pH 9.3). A decrease of the absorbance was recorded at 635 nm for 5 min at 25?C. The linearity was established applying the tangent method within the concentration range of lisinopril from 0.8-6.4 ?g mL-1, the detection and quantification limits being 0.158 ?g mL-1 and 0.480 ?g mL-1, respectively. The method has been successfully applied in three brands of tablets containing lisinopril alone or in combination with hydrochlorothiazide.

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The determination of boron in saline waters with Nile Blue A

Analytica Chimica Acta ◽

10.1016/s0003-2670(01)80120-3 ◽

1971 ◽

Vol 56 (1) ◽

pp. 147-149 ◽

Cited By ~ 11

Author(s):

R.A. Nicholson

Keyword(s):

Nile Blue ◽

Nile Blue A ◽

Saline Waters

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Evidence for Dual Site Binding of Nile Blue A toward DNA: Spectroscopic, Thermodynamic, and Molecular Modeling Studies

ACS Omega ◽

10.1021/acsomega.0c04775 ◽

2021 ◽

Vol 6 (4) ◽

pp. 2613-2625

Author(s):

Mukti Mohammad ◽

Harun Al Rasid Gazi ◽

Kumud Pandav ◽

Prateek Pandya ◽

Md. Maidul Islam

Keyword(s):

Molecular Modeling ◽

Nile Blue ◽

Nile Blue A ◽

Modeling Studies ◽

Molecular Modeling Studies ◽

Dual Site ◽

Site Binding

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Inversion of the Dorso-ventral Axis in Amphibian Embryos by Unilateral Restriction of Oxygen Supply

Development ◽

10.1242/dev.6.3.486 ◽

1958 ◽

Vol 6 (3) ◽

pp. 486-490

Author(s):

S. Løvtrup ◽

A. Pigon

Keyword(s):

Oxygen Supply ◽

Nile Blue ◽

Bilateral Symmetry ◽

Radial Symmetry ◽

Point Of View ◽

Low Permeability ◽

Grey Crescent ◽

Protein Coat ◽

Amphibian Embryos

According to the hypothesis advanced by Løvtrup (1958) the supply of oxygen is one of the factors responsible for the determination of bilateral symmetry in amphibian embryos. The protein coat covering the outside of the egg is known to have a very low permeability (Holtfreter, 1943), and it was suggested in the hypothesis that the formation of the grey crescent consists in a stretching of this coat by which the permeability is increased (cf. the work of Dalcq & Dollander (1948) and of Dollander & Melnotte (1952) on permeability of Nile blue), in this way the radial symmetry of the egg is changed to a bilateral symmetry from a metabolic point of view. As a consequence of the increase in permeability those oxidative, energy-supplying processes which are associated with gastrulation are enabled to proceed at a higher rate at one side of the egg.

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On Colouring Epon-Embedded Tissue Sections with Sudan Black B or Nile Blue A for Light Microscopy

Journal of Cell Science ◽

10.1242/jcs.s3-104.65.109 ◽

1963 ◽

Vol s3-104 (65) ◽

pp. 109-115

Author(s):

S. M. McGEE-RUSSELL ◽

N. B. SMALE

Keyword(s):

Lipid Droplets ◽

Nile Blue ◽

Thin Sections ◽

Nile Blue A ◽

Sudan Black B ◽

Glass Slides ◽

Acetone Water ◽

Negative Effect ◽

Blue Background ◽

Dark Blue

Sections of osmium-fixed tissues embedded in epon 812 colour with either Sudan black B or Nile blue A solutions to reveal a variety of detail by direct microscopy with normal apochromatic or semi-apochromatic objectives. The clarity of the coloration gives a picture fully comparable to that seen by phase-contrast microscopy. The plastic is not removed, 1-µ sections or thinner sections down to green or gold, are mounted on clean glass slides by drying down from 20% acetone/water after flattening on a hot plate. Colouring is carried out at room temperature in Sudan black B (saturated solution in 70% alcohol) for 1 to 2 h. The result is a reversed or negative effect, for the epon plastic takes the stain avidly, but dense elements of the tissue do not, and appear white against a blue background of stained plastic. Lipid droplets retain a capacity to colour, becoming dark blue to blue-black. Nile blue sulphate ( 1% aqueous solution colours thin sections of tissue in 1 to 2 h at 60° C, acting apparently as a basic dye on most cell elements, and also colours lipid droplets dark blue. After both techniques the sections are mounted in Farrants's medium.

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Rapid quantification of polyhydroxyalkanoates (PHA) concentration in activated sludge with the fluorescent dye Nile blue A

Water Science & Technology ◽

10.2166/wst.2011.707 ◽

2011 ◽

Vol 64 (3) ◽

pp. 747-753 ◽

Cited By ~ 12

Author(s):

M. Oshiki ◽

H. Satoh ◽

T. Mino

Keyword(s):

Activated Sludge ◽

Wastewater Treatment Plants ◽

Nile Blue ◽

Maximum Level ◽

Fluorescence Measurement ◽

Batch Reactors ◽

Floc Size ◽

Nile Blue A ◽

On Line ◽

Rapid Quantification

The present study was conducted (1) to develop a rapid quantification method of polyhydroxyalkanoates (PHA) concentration in activated sludge by Nile blue A staining and fluorescence measurement and (2) to perform on-line monitoring of PHA concentrations in activated sludge. Activated sludge samples collected from laboratory scale sequencing batch reactors and full-scale wastewater treatment plants were stained with Nile blue A and their fluorescence intensities were determined. There was a high correlation (R2 > 0.97) between the fluorescence intensities of Nile blue A and PHA concentrations in activated sludge determined by gas chromatography. The Nile blue A staining and fluorescence measurement method allows us to determine PHA concentrations in activated sludge within only five minutes and up to 96 samples can be measured at once by using microplate reader. On-line monitoring of PHA concentrations in activated sludge was achieved by using a fluorometer equipped with a flow cell and the time point at which PHA concentration in activated sludge reached the maximum level could be identified. In addition, we examined the influence of pH, floc size and co-existing chemicals in activated sludge suspension on the fluorescence intensities of Nile blue A.

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