It is used in testing for lignin, a complex organic molecule that bonds to cellulose fibres and strengthens and hardens the cell walls in plants. In testing for lignin
Toluidine blue (TB) is a polychromatic dye which can absorb different colours depending on how it binds chemically with various tissue components. It first emerged in 1856, courtesy of a British chemist called William Henry Perkin. TB stains tissues via the phenomenon of ‘ metachromasia ‘. Many dyes can show metachromasia, but the thiazine group dyes such as TB are especially good for this type of staining. This phenomenon refers to how a dye stains tissue components a different colour from the dye solution and the rest of the tissue. Clear in xylene and coverslip. RESULTS: Mast cells violetBackground shades of blue Toluidine BlueStock Solution: Toluidine Blue O 1.0 gm70% alcohol 100.0 mlMix, solution is stable for 6 months. CAUTION: Avoid contact and inhalation.Working Solution: Toluidine blue, Stock 5.0 ml1% Sodium chloride 45.0 mlMake fresh, discard after use. PROCEDURE CARD MAST CELLS-TOLUIDINE BLUECONTROL: Skin TECHNIQUE: Cut paraffin sections 4µ. PROCEDURE: 1. Deparaffinize and hydrate to distilled water.2. Working Toluidene blue, 1-2 minutes.3. Rinse in distilled water, 3 changes.4. Deydrate quickly through the 95% and absolute alcohols.5. a test for the presence of hemoglobin in feces or urine. The toluidine can be in solution, in a tablet or impregnated onto absorbent paper. A positive test is the development of a green to blue color.  Tolonium chloride (INN, also known as toluidine blue or TBO) is a blue cationic (basic) dye used in histology and sometimes clinically. Toluidine blue solution is used in testing for lignin, a complex organic molecule that bonds to cellulose fibres and strengthens and hardens the cell walls in plants. A positive toluidine blue test causes the solution to turn from blue to pink There are three isomers of toluidine, which are organic compounds. These isomers are o-toluidine, m-toluidine, and p-toluidine. The o-stands for ortho -, m-stands for meta - , and p-stands for para - . The difference between these three isomers is the position where the methyl group (-CH 3) is bonded to the ring relative to the amino functional group (-NH 2); see illustration of the chemical structures below. The toluidines is poorly soluble in pure water but dissolve well in acidic water due to formation of ammonium salts, as usual for organic amines. ortho-and meta-Toluidines are viscous liquids, but para-toluidine is a flaky solid. This difference is related to the fact that the p-toluidine molecules are more symmetrical. The difference between these three isomers is the position where the methyl group (-CH 3) is bonded to the ring relative to the amino functional group (-NH 2); see illustration of the chemical structures below. Toluidine is not soluble in water but soluble in acidic aqueous solution. O-toluidine and m-toluidine are clear to pale yellow, oily liquid. But P-toluidine solidifies to an off-white crystalline solid at about 43 C as it has more symmetrical structure. They are sensitive to air and light and tend to darken on storage. 3. I. Abstract This report pertains to the use of o-toluidine in the manufacture of dyes and the potential for exposure to other chemicals in the processes involving o-toluidine. The goal is to provide responses to a group of six specific questions involving o-toluidine as a precursor, intermediate, or product. II. Cohort-specific discussion of exposures to o-toluidine from manufacture of magenta and other molecules a. Case and Pearson cohort: (1) There are 2 exposure groups of possible concern – the aniline group and the magenta group (Table 1, p. 214, Case and Pearson 1954). Toluidine is the other name of methylaniline or aminotoluene. There are three structural isomers, ortho-TOLUIDINE, meta-TOLUIDINE, and para-TOLUIDINE. O-toluidine and m-toluidine are clear to pale yellow, oily liquid. But P-toluidine solidifies to an off-white crystalline solid at about 43 C as it has more symmetrical structure. They are sensitive to air and light and tend to darken on storage.
http://bitesizebio.com/19048/toluidine-blue-a-histology-stain-for-mast-cells-and-other-things/ http://library.med.utah.edu/WebPath/HISTHTML/MANUALS/TOLUID.PDF http://medical-dictionary.thefreedictionary.com/o-toluidine+test https://en.wikipedia.org/wiki/Toluidine_blue https://en.wikipedia.org/wiki/Toluidine https://en.wikipedia.org/wiki/Toluidine http://www.chemicalland21.com/industrialchem/organic/TOLUIDINES.htm http://ntp.niehs.nih.gov/ntp/roc/thirteenth/protocols/otolconsultant_report_508.pdf http://www.chemicalland21.com/industrialchem/organic/TOLUIDINES.htm
what is toluidine used for