Fuchsine dyes

Applicable to Grade 4. It shall be made by the addn of 1/8 gallon of tert-butyl alcohol and 1/4 avoirdupois ounce of benzyldiethyl-(2,6ammonium benzoate to 100 gallons of ethyl alcohol that complies with the requirements of Grade 1. It shall be dyed with 1 part by wt of fuchsin dye to 500,000 parts by wt of alcohol... 

The migration of water in teeth was tried to be visualized using fuchsine dye as a colorant ([103], rosaniline hydrochloride C19H17N3 HCI). Fresh human molars were immersed into a slightly acidic aqueous fuchsine solution. As was expected, the water penetrated fast via the nerve canal into the pulpa and especially the roots were dyed red from fuchsine migrating inwards as well from the sample surface as from the nerve canal. After several days, it could be observed that water had migrated into the gap between the enamel and the dentine (edj). Generally the intensity of the colour increased with time, and the dentine took up the colour more readily than the enamel. 

Sch iff reagent A reagent used for testing for aldehydes and ketones it consists of a solution of fuchsin dye that has been decolorized by sulphur dioxide. Aliphatic aldehydes restore the pink immediately, whereas aromatic ketones have no effect on the reagent. Aromatic aldehydes and aUphatic ketones restore the colour slowly. 

IF (interference filter at 0.353 nm) IP21 (photomultiplier) (quarter-wave plate at 1.06 pm) FB (fuchsin dye cell). Corning and Schott glass filters are labeled by their catalog numbers. 

Chromeazurole (Alberon, C. I. Mordant Blue 29), a fuchsin dye, gives a red-violet color lake with beryllium in weakly acid solution. One drop of the test solution is treated on a spot plate with a drop of 2 iV sodium acetate and one drop of the yellow alcoholic dye solution. Quantities of beryllium above 1 y yield a deep violet color. Smaller amounts (down to 0.3 y) give a pink color with a blue edge adhering to the spot plate. Iron, aluminum, zirconium and copper salts likewise give color lakes with chromeazurole. These interferences can be avoided by masking with EDTA,NaF and tartaric acid. 

In the same period, Schiff also concocted the so called Schiff s reagent as a test to identify aldehydes this reagent is used today to determine the sequence of DNA fragments. It is a mixture of a fuchsine dye (which contains some aromatic amines) with sulfurous acid or bisulfite sulfonation by the latter dismpts the dye s conjugated chain and renders it colorless. In the presence of an aldehyde, a complex series of reactions with various products takes place initially the fuchsine s aromatic amines react with the aldehyde to produce aldimines, which further react with bisulfite to produce resonance-stabilized products, restoring the red fuchsine color. 

Unlike coal tar and tobacco, the link between naphthylamines and carcinogenicity was not discovered until the 1870s. Prior to that time, aU industrial dyes were derived from namral sources. However, with the advent of synthetic fuchsine dyes in Germany came reported cases of bladder cancer. When World War I interrupted the industrial cooperation between Germany and the United States, an American... 

Zhang, X., Zheng, S., Lin, Z., Zhang, J., 2012a. Removal of basic fuchsin dye hy adsorption onto polyacrylamide/Laponite nanocomposite hydrogels. Synthesis and Reactivity in Inorganic Metal 42, 1273—1277. 

The triaryknethane dyes are broadly classified into the triphenyknethanes (Cl 42000—43875), diphenylnaphthyknethanes (Cl 44000—44100), and miscellaneous triphenylmethane derivatives (Cl 44500—44535). The triphenyknethanes are classified further on the basis of substitution in the aromatic nuclei, as follows (/) diamino derivatives of triphenylmethane, ie, dyes of the malachite green series (Cl 42000—42175) (2) triamino derivatives of triphenylmethane, ie, dyes of the fuchsine, rosaniline, or magenta series (Cl 42500—42800) (J) aminohydroxy derivatives of triphenylmethane (Cl 43500—43570) and (4) hydroxy derivatives of triphenylmethane, ie, dyes of the rosoHc acid series (Cl 43800—43875). Monoaminotriphenyknethanes are known but they are not included in the classification because they have Httie value as dyes. 

The first triaryknethane dyes were synthesized on a strictiy empirical basis in the late 1850s an example is fuchsine, which was prepared from the reaction of vinyl chloride with aniline. Thek stmctural relationship to triphenylmethane was estabHshed by Otto and Fmil Fischer (5) with the identification of pararosaniline [569-61-9] as 4,4, 4 -triaminotriphenyknethane and the stmctural elucidation of fuchsine. Several different stmctures have been assigned to the triaryknethane dyes (6—8), but none accounts precisely for the observed spectral characteristics. The triaryknethane dyes are therefore generally considered to be resonance hybrids. However, for convenience, usually only one hybrid is indicated, as shown for crystal violet [548-62-9] Cl Basic Violet 3 (1), for which = 589 nm. 

In a variation of this method, isolation of the ben2hydrol derivative is not required. The methane base undergoes oxidative condensation in the presence of acid with the same or a different arylamine direcdy to the dye. New fuchsine [3248-91 -7] Cl Basic Violet 2 (16), is prepared by condensation of two moles of o-toluidine with formaldehyde in nitrobenzene in the presence of iron salts to give the corresponding substituted diphenylmethane base. This base is also not isolated, but undergoes an oxidative condensation with another mole of o-toluidine to produce the dye. 

In the present work the acid-base surface properties of three Al O samples for a chromatography are investigated acidic (I), basic (II) and neutral (III) ones with the using of heterogeneous titration of their suspensions by HCl and NaOH solutions. To establish the correlations between the acid-base and adsoi ption properties studied Al O the representatives of cationic dyes -diamond green (DG), fuchsine (F) and anionic dyes - eriochrom black T and chromic dark blue have been used. 

Measurements show some variation depending upon the staining solution used and the method of application. In dried and fixed smears, the cell wall and slime layer do not stain with weakly staining dyes such as methylene blue but do stain with the intensely staining pararosaniline, new fuchsin, crystal violet, and methyl violet. The great majority of bacteria have been measured in fixed and stained preparations. In some instances dried, negatively stained smears have been used. Therefore, the method employed should be specified when measurements of bacteria are reported otherwise the results will be of doubtful v alue. 

The cell wall has a low affinity for dyes, which means that it is probably not stained in some of the usual staining procedures. It is lightly stained by certain basic dyes such as basic fuchsin and the methyl violets. Where deep staining of the wall is desired, the use of a mordant, such as tannic acid, is necessary. The mordant not only increases the affinity of the cell for dye, but it may increase the thickness of the wall. 

The entire group of these compounds dates back to the very beginnings of organic dye chemistry. In 1858, E. Verguin in France oxidized a material which he named aniline but which was in actual fact a mixture of aniline, o-toluidine, and p-toluidine. He performed the reaction in nitrobenzene in the presence of tin(IV)chloride or iron(III)chloride and received bluish red fuchsin (120). The process has been industrially exploited since 1859. The central carbon atom is furnished by the CH3 group of p-toluidine, which is initially oxidized to its aldehyde. 

The technical preparation of crystal violet and of its methyl-free parent substance, parafuchsine, almost the oldest of the triphenylmethane dyes, is not so easily explained. As is well known, in this process aniline and p-toluidine are united by oxidation in an acid melt. (In the preparation of fuchsine itself, which contains a methyl group attached to one of the benzene rings, o-toluidine is an additional ingredient.) Although all the phases of this important synthesis have not yet been experimentally established, we may nevertheless explain it on the basis of a dehydrogenation similar to that involved in the formation of malachite green. Moreover, the union of several molecules of base proceeds exactly according to the principle on which indamines are formed (p. 321) (Bucherer). 

Those dyes which, in contrast to malachite green and crystal violet, do not have the nitrogen in tertiary combination, for example, fuchsine, can lose water from their colour bases by direct elimination of its elements from their attachment to nitrogen and change into derivatives... 

Basic fuchsin (rosaniline, basic violet 14) or Pyronin Y are suitable as tracking dye. 

Exposure to ori/70-toluidine was reported to occur in an Italian plant producing fuchsin (magenta) and safranine T-based dyes (Rubino et al., 1982), in a German plant producing 4-chloro-ori/70-toluidine (Stasik, 1988) and in a plant producing rubber chemicals in the United Kingdom (Sorahan et al, 2000), but no data on exposure levels were provided. 

This scheme of frequency tripling was successfully tested with fuchsin in hexafluorisopropanol (a solvent selected for its low index of refraction and relatively flat dispersion curve) to frequency-triple the output of a neodymium laser 67,68) With an input power of 10 MW/cm2 a third-harmonic output of 0.2 mW/cm2 was measured. This low value was mainly due to the relatively high absorption of fuchsin at 355 nm. An improvement of the efficiency by a factor of 80 was found with hexamethylindocarbocyanine iodide in hexafluorisopropanol because of the much lower absorption of this dye at 355 nm. Since the absorption minimum of this dye is at 383 nm, one could expect an additional efficiency increase by a factor of 70 for a fundamental laser wavelength of 1.15 / 69>. Other cyanine dyes have been used for frequency tripling a fundamental wavelength of 1.89 /mi 70>. 

Photochemical preparation of stable dyes by irradiation of aminotriarylacetonitriles Photosensitive leucocyanide compositions Photoactivation of leucocyanides Solid photosensitive compositions Purification of triarylrnethane leucocyanides Fuchsine cyanide... 

If the aqueous solution is Orange yellow if it assumes a fuchsine-red colour on treatment with HC1 if it gives a violet colour when evaporated to dryness and then taken up with concentrated sulphuric add if this sulphuric acid solution changes to fuchsine-red on dilution if it dyes wool in an acid bath... 

If the wool thus obtained, after thorough washing with cold water, is coloured distinctly red, the conclusion may be drawn that the wine was coloured artificially with an organic dye of acid character, i.e., with a sui-phonated azo- or fuchsine derivative (vinolin, Bordeaux red, etc.)... 

The more common and more important red lakes are those of cochineal, red wood, alizarin (or madder) and its derivatives, triphenylmethane dyes (fuchsine), safranine, eosin, developed and sulphonated azo-dyes the last give also orange lakes. 

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