Description
Hydroxynaphthol blue, a well-known pH indicator in the field of biomedicine, is employed to accurately quantify pH fluctuations in various biological specimens. Besides, its utility extends to serving as a colorimetric reagent, notably in laboratory settings, aiding in the identification of select pharmaceuticals and ailments.
Chemical Properties
blue crystalline powder
Uses
Hydroxynapthol Blue is a pharmaceutical dye used in colorimetric analyses.
Purification Methods
The crude material is treated with hot EtOH to remove soluble impurities, then dissolve in 20% aqueous MeOH and chromatographed on a cellulose powder column with propanol/EtOH/water (5:5:4) as eluent. The upper of three zones was eluted to give the pure dye which is precipitated as the monosodium salt trihydrate by adding conc HCl to the concentrated eluate [Ito & Ueno Analyst 95 583 1970]. It can be converted to the trisodium salt wih the calculated amount of alkali. Indigocarmine (2[1,3-dihydro-3-oxo-5-sulfo-2H -indol-2-ylidene]-2,3-dihydro-3-oxo-1H -
