Sudan III

Solubility Insoluble in water soluble in benzene, chloroform moderately soluble in acetone, ether, petroleum ether slightly soluble in ethanol, xylene Melting Point 195 °C 

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

Staining Applications Lipids fats skin lips ° lipsticks contact lens eye shadow keratin fibers hairs latex particles nail enamel sun-screen ° spinal fluid  

Biological Applications Antiseptic preventing prostate cancer medical devices dental impression materials  

Industrial Applications Plasma display panels liquid crystal displays dielectric materials photore- 

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The use of an indicator or marking substance, which is adsorbed on the column in a position in known relation to that of the colourless substance (e.g., Sudan III for isolation of Vitamin D upon alumina). 

The sensor for the measurement of high levels of CO2 in gas phase was developed, as well90. It was based on fluorescence resonance energy transfer between 0 long-lifetime ruthenium polypyridyl complex and the pH-active disazo dye Sudan III. The donor luminophore and the acceptor dye were both immobilized in a hydrophobic silica sol-gel/ethyl cellulose hybrid matrix. The sensor exhibited a fast and reversible response to carbon dioxide over a wide range of concentrations. 

Aldehyde groups stain pink Lipids and fatty acids—Sudan III Unfixed or fixed frozen sections Take sections to 50% aqueous ethanol... 

Stain in Sudan III in 70% ethanol for 30 min Rinse sections in 50% aqueous ethanol Mount in glycerine... 

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].

The second experimental system explored the reduction mechanism of another azo-dye, known as Sudan III (I-(4-pheuyIazophenyIazo)-2-naphthoI) [91]. Sudan III contains two azo groups rendering two successive two-electron, two-proton reduction steps at the mercury surface. Figure 2.68 shows a typical SW voltammetric response of Sudan III recorded in a borate buffer at pH 10.00. The first reduction step is chemically reversible, while the second one is irreversible. More importantly, the second reduction step proceeds at potential about 230 mV more negative than the first one, thus causing a well-separated voltammetric peak. The overall mechanism... 

Fig. 2.68 Square-wave voltammogram of 5 x 10 mol/L SUDAN III solution recorded in a Ixuate buffer at pH = 10. The experimental conditions are itacc = —0.2 V, = 30 s, = 30 mV, / = 100 Hz and ML = 4 mV. Symbols 4, 4, and /net correspond to the cathodic, anodic and net current components of the SW response (reprinted from [91] Croat Chem Acta 76 37)...

To obtain a true k in MEEKC, it is important to trace the migration of the pseudostationary phase accurately. Sudan III, timepidium bromide, and quine, which have generally been used as tracers for micelles in MEKC, could not be employed as tracers for microemulsions consisting of sodium dodecylsulfate salt (SDS) or cetyltrimethylammonium bromide (CTAB), n-butanol and heptane (12). An iteration method based on a linear relationship between log k and the carbon number for alkylbenzenes (13) seems to provide a reasonable value of the migration time of the microemulsions. Dodecylbenzene shows a migration time larger than the value calculated by the iteration method and those of other hydrophobic compounds, such as phenanthrene, fluoranthrene, and Sudan III (Table 1). Methanol and ethanol were used as tracers for the aqueous phase. 

Butanol and methanol were used in most applications of microemulsions. Ishihama et al. investigated the effect of alcohol on the migration factor of the solute in different systems and on the migration of SDS micelles with or without alcohol. Sudan III migrated as tracer for micelles of SDS faster than dodecylbenzene in the SDS/butanol system (10-12). Due to the addition of butanol to the ME solution, the CMC values decrease very sharply. 

Fox 9) attempted to determine whether oils penetrated the eggs of the leaf roller Archips argyrospila. Eggs were immersed in petroleum oils saturated with Sudan III... 

Succinic anhydride Sudan I Sudan II Sudan III Sudan Brown RR Sudan Red 7B Sulfafurazole... 

As a result of checking a series of dyes, it has been found that the dye Sudan III—IV (mixture) is sorbed defectively by KL-3 preparations. The intensity of dyeing to a reddish-orange color is so strong that it is possible to determine particles of the adhesive in the preparation up to a size of 3 pm (Ref.15>, p. 69). Microscopic investigations of the experimental material have been performed in glueing wound surfaces of different animal organs by the KL-3 adhesive. The results... 

Fig. 7a and b. Fragments of adhesive KL-3 in cytoplasm of macrophages on polymer surface (a) and at some distance from it (b) 14 days after application on rabbit liver. Selective dyeing with Sudan III to IV, additional dyeing with hema-toxylene... 

To calculate the capacity factor, it is necessary to know the migration time not only of the analyte but also of the micelle and the EOF. Although there is no ideal marker in MECC, a very hydrophobic molecule, such as Sudan III, will spend most of its time partitioned in the micellar phase and... 

Amin described a simple and sensitive spectrophotometric method for the determination of three gyrase inhibitors, including ciprofloxacin, in pharmaceutical formulations [10]. This method is based on the formation of an ion pair with Sudan III in 40% v/ v aqueous acetone. The color of the dye changes at 566 nm in the presence of ciprofloxacin. Beer s law is obeyed over the range of 0.4-10.4 pg/mL, and the results showed good recovery (100 1.7%) with a RSD of 1.08%. 

Paul and McSpadden studied the permeation of a red organic dye (Sudan III) in acetone through a silicone rubber membrane as shown in Figure 6.9. The partition coefficient of 0.148 has been independently determined for the dye in the membrane and in acetone by an extraction method. Calculate the diffusion coefficient and the solubility of the dye. Assume that the thickness and the diameter of the membrane are 0.15 cm and 8 mm, respectively. 

There is no difficulty in testing whether a given emulsion is of the oil-in-water or water-in-oil type. Three methods are available the oil-in-water type has a much higher electrical conductivity than, the inverted type, because the conducting phase is the continuous one the oil-in-water type mixes easily with a drop of water, but not with oil, while the water-in-oil type mixes with oil, not water and the oil-in-water type is easily stained with water-soluble dyes, the other type being stained by oil-soluble dyes such as Scharlach R or Sudan III. 

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. 

SOMALIA RED III SOUDAN III STEARIX SCARLET SUDAN III SUDAN G SUDAN G III SUDAN III (G) SUDAN P HI SUDAN RED III TETRAZOBENZENE-p-NAPHTHOL TONEY RED TONY RED... 

Fig. 21.5 Cholesterol ester storage disease (CESD). Micro-/macro-vesicular fat droplets in hepatocytes and foam cells in a portal tract (Sudan III)...

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