Colour Spot Test
Definition
A presumptive identification reaction in which a small amount of concentrated fraction is treated with a chromogenic reagent (Marquis, Mecke, Mandelin, Mayer, Dragendorff, Wagner) on a white spot tile. The colour produced narrows the drug class before TLC and instrumental confirmation.
Related terms
- Ammonium Sulphate Modification
- The Otto variant in which saturated (NH4)2SO4 is added to a protein-rich homogenate (liver, kidney, blood) to salt out proteins before partitioning....
- Defatting
- A clean-up step before partitioning in which the acidified aqueous is washed with petroleum ether or n-hexane to remove fats, waxes and...
- Fraction a
- The acidic ether extract obtained by partitioning the acidified aqueous tissue digest with diethyl ether at pH 2 to 3. Contains barbiturates,...
- Fraction B
- The alkaline chloroform extract obtained after basifying the residual aqueous to pH 9 to 10 with ammonium hydroxide and partitioning with chloroform....
- Stas-Otto Method
- Sequential acid-alkaline solvent partitioning that isolates organic poisons from biological matrix in two fractions: acidic ether (Fraction A) for acidic and neutral...
Explained in
- Classical Extraction: Stas-Otto and Ammonium Sulphate MethodsA presumptive identification reaction in which a small amount of concentrated fraction is treated with a chromogenic reagent (Marquis, Mecke, Mandelin, Mayer,...