Naphthalene Sulfonic Acid Research Articles

High Performance Liquid Chromatographic Determination of Intermediates and Two Reaction By-Products in FD&C Red No. 40: Collaborative Study

Abstract Nine laboratories participated in a collaborative study of an ion exchange high performance liquid chromatographic procedure for determining the intermediates and 2 reaction by-products in FD&C Red No. 40: cresidine sulfonic acid (CSA), Schaeffer’s Salt (SS), 4,4’-(diazoamino)bis(5-methoxy-2-methylbenzenesulfonic acid) (DMMA), and 6,6’-oxybis(2- naphthalenesulfonic acid) (DONS), respectively. The repeatability and reproducibility standard deviations (absolute) found in the study were 0.012 and 0.019 for CSA at the 0.2% level, 0.004 and 0.006 for DMMA at the 0.1% level, 0.067 and 0.087 for DONS at the 1% level, and 0.015 and 0.020 for SS at the 0.3% level, respectively. The method has been adopted official first action.

High Performance Liquid Chromatographic Determination of Sulfanilic Add, Schaeffer’s Salt, 4,4´-(Diazoamino)-DibenzenensuIfonic Acid, and 6,6´-Oxybis(2-Naphthalenesulfonic Acid) in FD&C Yellow No. 6: Collaborative Study

Abstract Eight laboratories participated in a collaborative study of a high performance liquid chromatographic procedure for determining sulfanilic acid, Schaeffer's salt, 4,4´-(diazoamino)-dibenzenesulfonic acid (DAADBSA), and 6,6´-oxybis(2-naphthalenesulfonic acid) (DONS) in FD&C Yellow No. 6. The standard deviations for one analysis in any one laboratory for sulfanilic acid at 0.2%, Schaeffer's salt at 0.26%, DAADBSA at 0.1%, and DONS at 1.0% were 0.015%, 0.014%, 0.018%, and 0.077%, respectively. The method has been adopted as official first action.

Automated High Pressure Liquid Chromatographic Determination of Uncombined Intermediates in FD&C Red No. 40 and FD&C Yellow No. 6

Abstract An automated high pressure liquid chromatographic (HPLC) method is presented for the isolation and determination of uncombined intermediates in FD&C Red No. 40 (Allura Red AC) and FD&C Yellow No. 6 (CI No. 15985). Samples of FD&C Red No. 40 containing 0.1-0.4% cresidine sulfonic acid (4-amino-5-methoxy-2-methyl benzene sulfonic acid), 0.1-0.3% Schaeffer's salt (6-hydroxy-2-naphthalene sulfonic acid), 0.02- 0.08% 4,4'- (diazoamino) -bis (5-methoxy-2-methyl benzene sulfonic acid), and 0.1-1.0% 6,6'-oxybis (2-naphthalene sulfonic acid) were prepared and analyzed by this method. Recoveries ranged between 95 and 101%. Sixty samples of FD&C Red No. 40 were analyzed by the automated HPLC method. Results showed good agreement with those of the manual HPLC method. Samples of FD&C Yellow No. 6 containing 0.1-0.4% sulfanilic acid (4-aminobenzene sulfanilic acid), 0.1-0.3% Schaeffer's salt, 0.02-0.08% 4,4'-(diazoamino)-dibenzene sulfonic acid, and 0.2-1.0% 6,6'-oxybis (2-naphthalene sulfonic acid) were prepared and analyzed by this method. Recoveries ranged between 96 and 101%. Forty samples of FD&C Yellow No. 6 were analyzed by the automated HPLC method. Results showed good agreement with those of the manual HPLC method.

Possible Ion-Pair-Mediated Absorption of Mixidine II: Plasma Levels and Histology

Plasma intact 14C-mixidine levels in rats increased when the drug was administered intraduodenally with 1:3 and 1:5 molar ratios of 2-naphthalenesulfonic acid. Upon histological examination of the duodenums, similar doses of mixidine combined with Z-naphthalenesulfonic acid produced no dose-related lesions. These and previous observations demonstrate that mixidine absorption may be enhanced by ion-pair formation.

Biological and toxicological effects of solvent extraction chemicals: Range finding acute toxicity in the rainbow trout ( Salmo gairdnerii Rich.) and in the rat ( Rattus norwegicus L.)

The acute toxicity of twelve solvent extraction chemicals was studied in the albino rat after intraperitoneal injection of the chemicals, and in the rainbow trout ( Salmo gairdnerii Rich.) after exposure to the chemicals in the aquaria water. The tested chemicals included the following technical products: one primary aliphatic amine (Primene JM-T), two secondary aliphatic amines (Amberlite LA-1 and Adogen 283), two tertiary aliphatic amines (Adogen 383 and Alamine 336), one quaternary amine (Aliquat 336), two organophosphorus compounds (TBP, tributyl phosphate and HDEHP, di-(2-ethyl)-hexylphosphoric acid), one synthetic carboxylic acid (Versatic 10), one naphthalene-sulphonic acid (NA-SUL AS-50), one substituted oxime (LIX 64N) and one aliphatic alcohol (2-ethylhexanol). The intraperitoneal 96 hours LD 50 in the rat for the tested chemicals varied between less than 50 mg/kg b.w. to more than 5000 mg/kg b.w. Ninety six hours LC 50 in the rainbow trout was not possible to determine for three of the twelve tested chemicals due to their low water solubility. When determined, the LC 50 at 15°C was in the range 0.11–56 mg/l based on the amounts added. The present study discusses the acute toxicity of the chemicals mentioned above, gross pathological changes in the rat and behavioural changes in the fish.

Purity of Schaeffer's Salt

Abstract Twenty-one samples of Schaeffer's salt from 8 countries were evaluated for purity, using a variety of instrumental and chemical methods. The properties considered include strength, moisture, insoluble materials, inorganic salts, 2-naphthol, 2-naphthol-3,6-disulfonic acid, 2-naphthol-6,8-disulfonic acid, 6,6'-oxybis(2- naphthalenesulfonic acid), pH, ultraviolet purity, and absorptivity. One unknown was detected in the samples studied, and poor analytical totals obtained on several samples suggest the possible presence of others.

Liquid-liquid extraction of complexed metal ions by inclusion in dinonyl naphthalene sulphonic acid micelles

Most metal ions are complexed to some extent in aqueous solutions by organic acids such as di(2-ethylhexyl) phosphoric acid (HDEHP). The degree of complexation and the dimensions of the complexed ions are important factors for their inclusion in the micelles of dinonyl naphtalene sulphonic acid (HD) present in an organic phase. This behaviour is demonstrated by the liquid-liquid extraction of metal ions. The strong tendency of HD to adhere at the interface of the organic and the aqueous phase facilitates a study of the heterogeneous reactions which take place at the interface.

Study of microwave absorption and molecular structure of some substituted naphthalene sulphonic acids and their dipolar mixture

The dielectric constant (∈′) and the loss factor (∈″) of naphthalene sulphonic acid, 0-naphthol sulphonic acid, l-naphthylamine 8-sulphonic acid and 2–4 dinitro naphthol 7-sulphoinc acid and their dipolar mixture in dilute solution of dioxane have been determined at three temperatures (20°, 30° and 40° C) in 3·13 cm (9585 Mc/sec.) microwave region by concentration variation method. The data obtained have been used for determining the relaxation times. The values of relaxation times at different temperatures have been used to determine free energy, heat and entropy of activation for the process of dipole orientation. It has been concluded that the dipole orientation in the molecules is contributed by both molecular as well as intra-molecular rotations. In case of dipolar mixture the relaxation time is average of the two components.

The complete sequence of sheep beta-endorphin

Automatic sequencing of an isothiocyano naphthalene sulfonic acid derivative of sheep beta-endorphin, allowed the positioning of 24 out of 31 residues. Peptide mapping of a tryptic digest of the native molecule permitted the filling of remaining gaps. The complete sequence of this pituitary peptide was found to be identical to that of the portion 61–91 of sheep-beta-lipotropin.

Sulphate and fluoride complexing of U(VI), Np(VI) and Pu(VI)

The complex formation of U(VI), Np(VI) and Pu(VI) with sulphate and fluoride ions was studied in HClO 4H 2SO 4 and HClO 4HF solutions respectively at an ionic strength of 2·0 and [H +] = 2·0 M by the distribution method employing the liquid cation exchanger dinonyl naphthalene sulphonic acid as the extractant. An attempt was made to explain the order of the stability constant values obtained.

Fluorescent labeling of human platelets

Noncovalently bound fluorescent probes have been used to study changes in the platelet which may occur during platelet aggregation. Platelets were exposed to either N-phenyl-naphthylamine (NPN) or 8-anilino-1-naphthalene-sulfonic acid (ANS). Both dyes were bound by the platelet, and platelet aggregation by collagen or thrombin was unaffected by the presence of the label. No change in fluorescence intensity or wavelength of maximum intensity was observed during platelet aggregation.

Fluorescent Labeling of Human Platelets

Abstract Noncovalently bound fluorescent probes have been used to study changes in the platelet which may occur during platelet aggregation. Platelets were exposed to either N-phenyl-naphthylamine (NPN) or 8-anilino-1- naphthalene-sulfonic acid (ANS). Both dyes were bound by the platelet, and platelet aggregation by collagen or thrombin was unaffected by the presence of the label. No change in fluorescence intensity or wavelength of maximum intensity was observed during platelet aggregation.

Solvent extraction studies with dinonyl naphthalene sulphonic acid: Separation of protactinium(V) from the other mixed metal ions

The use of dinonyl naphthalene sulfonic acid (HD) in the organic solvents as an extractant has been shown to be a simple and effective method for the separation of metallic ion from the others with the proper choice of acidic aqueous solution and with the aid of long-chain alcohols or some complexing agents. In the present paper, the method for the separation of 233Pa from a mixture of various metal ions by the use of HD in n-hexane solution has been investigated. The average recovery of 233Pr by this method was found to be more than 95%.

Inclusion of some organic acids in micelles of dinonyl naphthalene sulfonic acid

The volume of the core of a micelle of dinonyl naphthalene sulfonic acid is about 1670 Å 3. This volume can be occupied by 56 water molecules but also by other molecules. Vapor pressure measurements show that molecules of di(2-ethylhexyl) phosphoric acid can be included. The similarity in behavior toward metal-ion extraction indicates that other organic acids, for instance, 2-ethylhexyl phenyl phosphonic acid and stearic acid can be included also.

Determination of the aggregation number of dinonyl naphthalene sulfonic acid by metal ion extraction

Variation of the concentration of a polyvalent metal ion in the solvent extraction reaction with dinonyl naphthalene sulfonic acid in aliphatic solvents enables the measurement of the aggregation number of the acid. The value obtained, 7, is confirmed by the experimentally determined dimension and volume of the micelle.

Determination of Uncombined Intermediates in FD&C Yellow No. 6 by High-Pressure Liquid Chromatography

Abstract A high-pressure liquid chromatographic method is presented for the isolation and determination of uncombined intermediates in FD&C Yellow No. 6 (sunset yellow FCF, CI. No. 15895). Samples of FD&C Yellow No. 6 containing 0.1-0.4% sulfanilic acid, 0.1-0.4% 6-hydroxy-2-naphthalenesulfonic acid, and 0.3— 1.0% 6,6'-oxybis(2-naphthalenesulfonic acid) were prepared and analyzed using this method. Recoveries ranged between 94 and 101%. Twenty-two samples of FD&C Yellow No. 6 were analyzed by the conventional column elution chromatographic method as well as by the high-pressure liquid chromatographic method. Good agreement was obtained between the 2 methods.

High-Pressure Liquid Chromatographic Determination of Uncombined Intermediates in FD&C Red No. 40

Abstract A high-pressure liquid chromatographic method was developed for the isolation and determination of uncombined intermediates in FD&C Red No. 40 (Allura Red AC, food color). Samples of FD&C Red No. 40 containing 0.1–0.4% cresidine sulfonic acid, 0.1–0.4% Schaeffer's salt, and 0.3–1.0% 6,6'-oxybis(2-naphthalenesulfonic acid) were prepared and analyzed using this method. Recoveries ranged between 92 and 101%. When 32 samples of FD&C Red No. 40 were analyzed by the conventional column chromatographic method as well as by the high-pressure liquid chromatographic method, good agreement was obtained between the 2 methods.

On the utilization of dinonyl naphthalene sulfonic acid for the determination of environmental uranium concentration in air, sea water, and soil.

On the utilization of dinonyl naphthalene sulfonic acid for the determination of environmental uranium concentration in air, sea water, and soil.

Study of the sulphate complexing of Np(IV) and Pu(IV) by solvent extraction with dinonyl naphthalene sulphonic acid

The complex formation of Np(IV) and Pu(IV) with sulphate ions was studied in perchloric-sulphuric acid solutions at an ionic strenght of 2·0 and [H +] = 2·0 M by the distribution method using the liquid cation exchanger. Dinonyl naphthalene sulphonic acid as an extractant. Also the sulphate complexing of Pu(IV) in perchloric-sulphuric acid solutions was studied using the TTA extraction method. The values of the formation constants are compared with the literature values.

Uncombined Intermediates in FD&C Red No. 40

Abstract The results of a collaborative study are reported. Nine collaborators from industry and government analyzed 3 samples each. The intermediates were separated from FD&C Red No. 40 and from each other on a cellulose column, using 40 and 20% aqueous ammonium sulfate as eluants, and were quantitated by UV spectrometry. Cresidinesulfonic acid, Schaeffer’s salt, and 6,6′-oxybis(2-naphthalenesulfonic acid) were recovered at an average level of 99.7%. Between-laboratory standard deviations ranged from 0.007 to 0.072% when the intermediates were present at levels of 0.03 to 1.00%. The method has been adopted as official first action.