Lymphangiography reaction

Patent Blue V, also called Food Blue 5, Sulphan Blue, Acid Blue 3, L-Blau 3, C-Blau 20, Patentblau V, Sky Blue, or C.I. 42051, is a sky blue synthetic triphenylmethane dye used as a food coloring. As a food additive, it has E number E131. [Source: Wikipedia ]