Low Temperature Sulfation of Tissues and the Demonstration Of Metachromasy

Sulfation of tissue sections which contained nonmetachromatic polysaccharides was done in an equivolume mixture of concentrated sulfuric acid and glacial acetic acid at 0°C. The sections were washed successively in glacial acetic acid and water. Aqueous solutions of toluidine blue, 1.5 × 10-4 M, were used for staining. The procedure produced a metachromatic substrate in sites previously nonmetachromatic. Normal metachromasy was unaffected. There was no loss, damage or distortion of the tissue sections.