Rhodamine G, reagent

Preparations are incubated with appropriate reagents to allow visualization based upon the detection system associated with the secondary antibody. The secondary antibody may be conjugated to a enzyme (e.g., alkaline phosphatase, horseradish peroxidase). Incubation with the appropriate substrate to the enzyme will result in the production of an insoluble colored product that can be detected upon microscopic analyses of the cells. Secondary antibodies can also be conjugated to fluorochromes (e.g., fluorescein, rhodamine) that can be detected using a microscope equipped to detect fluorescence. Immunohisto-chemistry has proven to be a powerful tool in biochemical toxicology allowing for in situ assessments of protein responses to toxicant exposure. 

The reagent is prepared by dissolving 0-01 g of rhodamine-B in 100 ml of water. A more concentrated reagent is obtained by dissolving 0-05 g of rhodamine-B in a 15 per cent solution of potassium chloride in 2m hydrochloric acid. 

The sensitive and selective spectrophotometric methods involve extraction of ion-associates of the GaCU" ion with basic dyes (e.g., Rhodamine B). Methods based on ternary complexes of gallium with chelating triphenylmethane reagents (e.g., Eriochrome Cyanine R) and some surfactants are very sensitive but less selective. 

Rhodamine B solution 0.03 g rhodamine B in 100 ml dist. water Rhodamine B mixing reagent ... 

Fig. 139. Thin-layer chromatogram of polar lipids [210]. Layer silica gel G solvent chloroform-methanol-water (65-h 25-f 4) time of run 2h spray reagents rhodamine B in ethanol (UV light) and Dragendorff-reagent amounts 50—100 (xg of each. 1 lysolecithin 2 sphingomyelin 3 lecithin 4 ethanolamine-cephalin ...

These acids, their esters and also o-phenylphenol, can be detected by introducing 0.02% of an optical bleach such as Ultraphor WT (Firm 16) into the adsorbent layer [22]. The substances may further be visualised by spraying with a rhodamine B solution (Rgt. No. 220) or a bromo-cresol green solution (Rgt. No. 25). Special spray reagents have been described for specific detection of the different types of preservative e. g., thiobarbituric acid (Rgt. No. 248) or thymol-sulphuric acid for sorbic acid hydrogen peroxide-ferric chloride for dehydroacetic acid and ferric chloride for salicylic acid. o-Phenylphenol, a fungicide, can be visualised with 2,6-dichloroquinonechloroimide (Rgt. No. 66), diazotised 4-nitroani-line solution (Rgt. No. 182) or cerium-(IV) sulphate-trichloroacetic acid (Rgt. No. 37). 

Detection techniques may be nondestructive or reversible, e.g., iodine or Rhodamine B, or destructive, e.g., sulfuric acid. Detection reagents are usually classified as general, i.e., those that react with a wide variety of different compound types, versus speciftc, i.e., reagents that indicate a particular compound or functional group. Some general reagents are destructive and others are not likewise, there are destructive and nondestructive specific chemical detection reagents. 

Often, the complex formation between antibody and antigen cannot be detected directly. In many cases, labeling of one of the reagents is necessary. Radioactive isotopes (e.g., H), fluorescent dyes (e.g., fluorescein, rhodamine), gold... 

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