Showing papers on "Brilliant green published in 1998"

Flow injection determination of anionic surfactants with cationic dyes in water bodies of central India

Abstract: A new, simple and specific flow injection analysis (FIA) procedure for the determination of anionic surfactants, viz., sodium lauryl sulfate (SLS), sodium dodecyl sulfonate, sodium hexadecyl sulfonate and sodium dodecyl benzenesulfonate, with cationic dyes, viz., Brilliant Green (BG), Malachite Green, Methylene Blue, Ethyl Violet and Crystal Violet, in water bodies, viz., ponds, tube wells, rivers and municipal wastes, of central India (east Madhya Pradesh) is described. It is based on the precipitation of the cationic dyes with the anionic surfactant due to formation of an ion-associate species within the pH range 5.5–8.0. The apparent molar absorptivity of the ion-associate species formed with various anionic surfactants and cationic dyes is in the range (0.60–1.50) × 104 l mol–1 cm–1 at λmax 590–665 nm. Among them, the pair BG+–LS– was selected for detailed investigation. The detection limit (amount causing absorbance >3s) of the method with BG is 100 ppb SLS and the sample throughput is 50 h–1. Optimization of FIA and the analytical variables in the precipitation and determination of SLS with BG is described. The method is free from interferences from almost all ions which are commonly present with the surfactant. The proposed method was applied to the mapping of SLS pollution levels in the various water bodies. All surface waters and municipal waste waters and some ground waters lying near the sources were found to be contaminated with SLS beyond permissible limits.

Resonance Rayleigh Scattering for an Indirect Determination of Trace Amounts of Selenium(IV) with Iodide-Basic Triphenylmethane Dye Systems

Abstract: The resonance Rayleigh scattering (RRS) spectra of selenium(IV)/iodide/basic triphenylmethane dye systems have been studied. Intense RRS appears when selenium(IV) reacts with iodide and a basic triphenylmethane dye, such as Crystal Violet (CV), Ethyl Violet (EV), Brilliant Green (BG), Malachite Green (MG) and Iodine Green (IG), to form an ion-association complex. The characteristics of the RRS spectra of the ion-association complexes and the suitable conditions for the reactions were investigated. The intensity of RRS is directly proportional to the concentration of selenium(IV) in the range 0 - 0.30 μg/25 ml for the CV and EV systems, and 0 - 0.40 μg/25 ml for other systems. The RRS methods have very high sensitivities for an indirect determination of selenium(IV); the detection limits are between 0.094 ng/ml and 0.86 ng/ml for different dye systems. A new way to determine trace amounts of selenium based on the RRS spectra of the ion-association complex has been developed.

Resonant Rayleigh scattering for the determination of trace amounts of mercury (II) with thiocyanate and basic triphenylmethane dyes

Abstract: Intense resonance Rayleigh scattering (RRS) appears when mercury (II) reacts with thiocyanate and a basic triphenylmethane dye (BTPMD), such as crystal violet (CV), ethyl violet (EV), brilliant green (BG), malachite green (MG) or indine green (IG), to form an ion-association complex of the type (BTPMD)2[Hg(SCN)4]. The characteristics of RRS spectra of the ion-association complexes and suitable conditions for the reactions were investigated. The intensity of RRS is directly proportional to the concentration of mercury (II) in the range of 0±2.0 μg/25 ml. The RRS methods have very high sensitivities for determination of mercury (II); their detection limits are between 1.68 ng/ml and 6.00 ng/ml on different dye systems. The effects of foreign ions and ways to improve the selectivity were studied. The new highly sensitive methods for the determination of trace amounts of mercury based on the RRS of the ion-association complexes have been developed.

Analysis of the Solvatochromic Behavior of the Disubstituted Triphenylmethane Dye Brilliant Green

Abstract: The coincident spectral components of the main visible absorption band of the triphenylmethane dye Brilliant Green can be resolved using a nonlinear least-squares fitting routine. This analysis reveals two Gaussian components, with centers near 600 and 630 nm, that possess additional spectral characteristics with a pronounced sensitivity to the dye's microenvironment. In particular, both the ratio of the heights of these Gaussian peaks and the ratio of their areas exhibit an inverted dependence on solvent dielectric constant, i.e., a reversal of solvatochromic behavior in media of low polarity. Such an absorption spectrum analysis facilitates the use of triphenylmethane dyes that lack symmetric trisubstitution of the phenyl rings as environment-sensitive spectroscopic probes. We demonstrate further the utility of this approach through the spectrophotometric determination of the critical micelle concentration of the anionic surfactant sodium dodecyl sulfate using Brilliant Green as an optical probe.

Determination of antimony in rain water at the nanogram level with surfactant and brilliant green

Abstract: A new, simple, selective and sensitive method for the spectrophotometric determination of antimony in rain water is described It includes preconcentrating Sb with surfactants (ie cetylpyridinium chloride (CPC) and Triton X-100 (TX-100)) into toluene and allowing the extract to react with a dye, ie brilliant green (BG) The value of apparent molar absorptivity is 555 × 105 L-mol–1· cm–1 at λmax = 620 nm; the detection limit is 3 ng/mL Sb in rain water at 3-fold preconcentration

Fractionation and spectrophotometric determination of thallium with N,N ′-diphenylbenzamidine, brilliant green and cetylpyridinium chloride

Abstract: A spectrophotometric method for the determination of inorganic chemical species of thallium i.e.Tl(I), Tl(III) and total Tl at trace level in industrial waste waters, effluents and surface water of...