Detection of Explosives: Dinitrotoluene and Nitroglycerin Test

A sample that contains dinitrotoluene and nitroglycerin in reaction with 20 % tetramethylammonium hydroxide gives blue color with DNT and dark green if nitroglycerin is present.

Equipment
Scale, 50 mL laboratory beaker, glass storage bottles, a spot plate (Fig. 1).

Materials and Chemicals
• 20 % tetramethylammonium hydroxide
• Solution of aceton and ethanol 1:1

Fig. 1. Materials

Fig. 2. Characteristic color of the test

Procedure
Place a few milligrams of solid sample or a drop of liquid sample in a spot plate and add one drop of a solution of equal parts acetone and ethanol followed by a drop of 20 % tetramethylammonium hydroxide. Formation of a blue color (Fig. 2) indicates DNT; the color will become dark green if nitroglycerin is present.