Division 3.23 Oxidation mixture (Performic acid — phenol):

Mix 0,5 ml hydrogen peroxide (3.1) with 4,5 ml formic acid-phenol solution (3.19) in a small beaker. Incubate at 20-30 ^oC for 1 hour in order to form performic acid, then cool on an ice-water bath (15 min.) before adding to the sample.

Caution: Avoid contact with skin and wear protective clothing.