Eosin materials

Fig. 200. Stoneman s silicosis from the Ruhr district. Haema-toxylin and eosin. (Material kindly provided by Prof. Husten t)...

Eosin (Tetrabromofluorescein). Place 16 5 g. of powdered fluorescein and 80 ml. of rectified (or methylated) spirit in a 250 ml. flask. Support a small dropping funnel, containing 36 g. (12 ml.) of bromine, above the flask make sure that the stopcock of the funnel is well lubricated before charging the latter with bromine. Add the bromine diopwise during about 20 minutes. When half the bromine has been introduced, and the fluorescein has been converted into dibromofluor-escein, all the solid material disappears temporarily since the dibromo derivative is soluble in alcohol with further addition of bromine the tetrabromofluorescein (sparingly soluble in alcohol) separates out. Allow the reaction mixture to stand for 2 hours, filter ofiF the eosin at the pump, wash it with alcohol, and dry at 100°. The yield of eosin (orange-coloured powder) is 25 g. 

Ammonium Salt of Eosin.-—Place a very stout filter paper on a flat-bottomed crystallising basin which is one-third full of concentrated aqueous ammonia solution, spread eosin to a depth of about 0-5 cm. on the paper, and cover the whole with a funnel. Very soon the light red crystals acquire a darker colour, and after about three hours they are completely converted into the ammonium salt, which forms dark red crystals having a green iridescence. When a sample of the material dissolves wholly in water the reaction is known to be complete. 

To obtain tissue preparations whose constituents were maintained as closely as possible to their state in vivo, the material had to be fixed, i.e. the enzymes inactivated so that cell structures were instantaneously preserved, an almost unattainable ideal. Formalin was the favored fixative, but others (e.g. picric acid), were also employed. Different methods of fixation caused sections to have different appearances. Further artifacts were introduced because of the need to dehydrate the preparations so that they could be stained by dyes, many of which were lipid-soluble organic molecules. Paraffin wax was used to impregnate the fixed, dehydrated material. The block of tissue was then sectioned, originally by hand with a cut-throat razor, and later by a mechanical microtome. The sections were stained and mounted in balsam for examination. Hematoxylin (basophilic) and eosin (acidophilic) (H and E staining) were the commonest stains, giving blue nuclei and pink cytoplasm. Eosinophils in the blood were recognized in this way. 

The method of Koyama et al.12 was used to determine the parakeratotic index of SC. A glass plate was attached to the skin with Scotch tape (Sumitomo 3M, Tokyo, Japan) measuring 25 x 19 mm to remove corneocytes. The adherent horny material was stained with hematoxylin-eosin solution for microscopic inspection of nuclei. The results were scored depending on the number of the nucleated cells in the visual field (0 = none, 1 = small, 2 = relatively large, 3 = very large). 

The plasmonic silver films put in pairs as an object-plate and a cover glass allow significantly (up to 3-4 times) increase the staining dyes fluorescence. This effect is observed in the case of optical tuning of LPs. The deposition of hematoxylin-eosine-poly-L-lysine moiety between two plasmonic silver films is carried out as a real biopsy material tincturing in histology. These results may be adopted for clinical assays with the use of biomedical fluorescent microseope. 

Aluminium causes histological changes at injection sites, and these stain with hematoxylin and eosin (53). Of four patients studied, one had a sclerosing lipogranu-loma-hke reaction with unhned cystic spaces containing crystalline material. Another presented as a large symptomatic subcutaneous swelling, which microscopically showed diffuse and widespread involvement of the subcutaneous tissues by a lymphoid infiltrate with prominent lymphoid follicles. 

Each paraffin-embedded section is collected on microscope slides and first examined under a microscope (lOx) to ensure that it contained sufficient tumor material and to eliminate possible contaminating normal tissues. Tumor and tumor-free areas are identified within 15 pm-thick deparaffinized sections lightly counterstained with hematoxylin and microdissected by gentle scraping with sterile scalpels into 1.5 ml polypropylene vials, using a hematoxylin and eosin-stained step section from the same block [4-7]. 

FIA system employing PAN immobilized on a cation-exchange resin (Dowex 50 W) was applied to determine Ni in steel, alloys, petroleum, mineral oil and waste water [5]. The method employing Xylenol Orange allows simultaneous determination of Ni and Fe in alloys and industrial waste water [6]. Ni (Fe, Co and Cu) in alloys and biological materials were simultaneously determined with the use of 1,5-bis(di-2-pyridylmethylene) thiocarbonohydrazide (DMF) [7]. 1,10-phenanthroline and eosine were employed to determine Ni in aluminium bronze [8]. The complex with dimethylglyoxime makes a basis of the determination of Ni in oil [9]. 

Core-needle biopsy samples are fixed in formalin and embedded in paraffin wax 3- to 4 pm-thick sections are cut and then stained with hematoxylin/eosin. Further immunohistochemical analysis of the material is then possible for specific indications requested. In all cases, the presence of a cytopathologist, to assess specimen adequacy during the procedure, would result in a high diagnostic outcome (Baled and Guy 2001) however, if this is not possible, two needle punctures during the first session should be performed. 

Commercial production of phthalic anhydride (PA) was taken up by BASFm 1872, by the oxidation of naphthalene with manganese dioxide and hydrochloric acid, to obtain the required base material (PA) for the manufacture of the dyestuffs fluorescein and eosine, and later for phenolphthalein however, the yield was only 5 to 7%. 

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