SUDAN IV

CA Index Name 2-Naphthalenol, l-[2-[2-methyl-4-[2-(2-methylphenyl)diazenyl]phenyl]diazenyl]- 

Molecular Formula C24H20N4O Molecular Weight 380.44 Physical Form Dark red-brown powder 

Solubility Insoluble in water soluble in benzene, methanol, acetone, isopropanol slightly soluble in ethanol 

Staining Applications Fat globules fats lipids fish oil lipoproteins CYPlAl proteins proteins starch nucleic acids tissues waxes  

Biological Applications Detecting atherosclerosis diapers skin care products shampoos hair colors stents dental impression materials  

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Sudan IV [Solvent Red 24, l-(4-o-tolylazo-o-tolylazo)-2-naphthol] [85-83-6] M 380.5, m -184 (dec), Cl 26105, Xmax 520nm, pK jt -9.0. Crystd from EtOH/water or acetone/water. 

Lipids Nile blue Sudan black B Sudan IV... 

Fig. 3.38.The IUPAC names of Sudan azo dyes are as follows Sudan 1 = 1— [(2,4-dimethylphenyl)azo]-2-naphtalenol Sudan II = l-(phenylazo)-2-naphtol Sudan III = l-(4-phenylazophenylazo)-2-naphtol Sudan IV = o-tolyazo-o-tolyazo-beta-naphtol and Disperse Orange 13 = 4-[4-(phenylazo)-l-naphtylazo]-phenol. Azo dyes were separated in an ODS column (250 x 2.1 mm i.d. particle size 5 /xm) at 35°C. The isocratic mobile phase consisted of 0.1 per cent formic acid in methanol-0.1 per cent formic acid in water (97 3, v/v). The flow rate was 200 /xl/min. MS conditions were nebulizing and desolvation gas were nitrogen at the flow rates of 50 and 5551/h, respectively electrospray voltage, 3.0 kV cone voltage 25 V source temperature, 110°C desolvation temperature, 110°C. Azo dyes were extracted from the samples by homogenizing 1 g of sample with 10 ml of acetone, then the suspension was centrifuged and an aliquot of 3 ml of supernatant was mixed with 1 ml of deionized water, filtered and used for analysis. LC-ESI-MS/Ms SRM traces of standards and spiked samples are listed in Fig. 3.39. It was found that the detection and quantitation limits depended on both the chemical structure of the dye and the character of the accompanying matrix. LOD and LOQ values in chilli tomato sauce...

Fig. 3.39. LC-ESI-MS/MS SRM traces obtained from 125 pgfi standard solution of (a) Sudan I (b) Sudan II (c) Sudan IE (d) Sudan IV (e) Disperse orange 13 internal standard (100 /zg/1 left column) and from a blank chilli tomato and cheese sauce sample spiked with 125 pgfl each (1 685 jug/kg sample) of (f) Sudan I (g) Sudan II (h) Sudan III (i) Sudan IV (j) Disperse orange 13 internal standard (100 /ig/1 right column injection volume 20 p). Reprinted with permission from F. Calbiani et al. [115].

F. Calbiani, M. Careri, L. Elviri, A. Mangia, L. Pistara and I. Zagnoni, Development and in-house validation of a liquid chromatography-electrospray-tandem mass spectrometry method for the simultaneous determination of Sudan I, Sudan II, Sudan II and Sudan IV in hot chili products. J. ChromatogrA, 1043 (2004) 123-130. 

Figure 2. Necrophylactic periderm in the bark of Picea siichensis following attempted infection by Armillaria obscura. Bark sectioned and stained with Sudan IV, after extraction with chlorine dioxide to remove aromatic compounds, essentially as previously described (15). NT, necrotic tissue TC, thickened cells SIT, relic of suberized impervious tissue NP, necrophylactic periderm. Scale bar = 25 /tm.

Figure 5. Heartwood of Quercus rofeur with advanced decay caused by Gan-oderma adspersum. Although the wood has been extensively degraded, suberized tyloses and vessel linings remain recognizable. Wood sectioned and stained with Sudan IV as previously described (15). Scale bar = 100 pm.

Red — KCIO 26, lactose 27, Sudan IV 27, Rhodamine B 14, Auramine 5 sucrose 1% Yellow — KC103 30, Auramine 0 65 kieselguhr 5%... 

Sudan IV [85-83-6] M 380.5, m 184°. Crystd from EtOH/water or acetone/water. 

Therefore, in MEKC, the only difference from chromatography, for nonionic solutes, is that the pseudostationary phase (the micelles) is not actually stationary, but slowly migrates toward the detector, eluting at a characteristic time. That time is determined experimentally by injecting a water-insoluble dye (e.g., Sudan III or Sudan IV), which is completely included in the micelles, and measuring its elution time. 

However, that both patients had myopathy of some kind was certain, and muscle biopsies were carried out. Formol-HgCla/paraflBn/hematox-yUn-eosin and formol/frozen/Sudan IV sections showed neither the pres-... 

Nifedipine was well tolerated, and evoked peak reduction in mean arterial pressure of less than 12 mm Hg. Plasma total cholesterol after eight weeks before killing the rabbits was similar in the placebo and nifedipine-treated groups, averaging 1,903 138 (n = 13) and 1,848 121 mg/dl (n = 13 mean SE P > 0.8). In placebo-treated rabbits, aortic lesions stainable with Sudan IV covered 40 5% of the intimal surface. 

Each longitudinal half-aorta was blotted and weighed. One-half was quickly frozen and stored at -70°C, the other laid flat, intimal side up, on clear plexiglas. The preparation was glued around its edges to the plastic with Permabond 910 (Permabond International Corp., Englewood, N.J.), and stained with Sudan IV (Sigma Chemical Co., St. Louis, Mo.) as described by Kramsch and Chan, 1978 Chan et al., 1978 and Holman et al., 1958 (4,... 

If precipitation lines contain a lipoid component, they can be stained with a combination of oil red and Sudan black (Ul), first using a solution of 1 g of oil red O or scarlet red R (Geigy) or Sudan IV dissolved in one liter of 60 % ethanol during 24 hours at 37 °G. The solution is filtered after cooling and kept in dark-colored bottles. The agar films remain 16 hours in this solution then they are soaked for 2 hours in a... 

Sudan red dyes are synthetically produced dyes normally used for colouring shoe and floor polish, oils, and solvents. For example, Sudan red is used to colour petroleum products to prevent misuse. The dye is added to diesel products to prevent substitution of less expensive fuel oils. Some of the Sudan dyes have been used in the past to colour foodstuffs however, many of these, including Sudan I (see Figure 11.7), Sudan III, and Sudan IV are now banned substances. Sudan dyes have been shown to cause cancer in animal studies and thus have been declared carcinogens. They are not permitted as an additive in any foodstuff in the United Kingdom and the rest of the European Union. 

In the membrane separation processes, the importance of the effect of possible associations between the solute and solvent and the membrane material is quite clear. This behavior resulting in differential permeation rates of solutes due to these phenomena of interactions can be observed in the case of retention of Sudan IV, an organic compound of molecular weight equal to 384 in this molecnle are present four aromatic rings, and its rejection by a hydrophobic membrane was 25% and 10%, respectively, when dissolved in n-hexane, at a pressnre of 15 bar, and methanol, 20 bar. Under the same conditions, a crossing of two solutions in a hydrophilic membrane was performed, resulting in the values of the retention of 86% for the compound in the solution of methanol and 43% for the same compound in the solution of n-hexane [23]. 

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