Potassium permanganate and tetraethylammonium chloride are a safe and effective substitute for osmium tetroxide in solid-phase fluorescent chemical cleavage of mismatch.

Whilst chemical cleavage of mismatch (CCM) detects all point mutations in DNA, its widespread use has been hampered by the complex multistage methodology and the need for toxic chemicals, in particular osmium tetroxide. Here we show that osmium tetroxide can be replaced by potassium permanganate, giving the same spectrum of mutation detection, but with greater sensitivity. The use of potassium permanganate is compatible with solid phase capture and fluorescent detection, giving a safer method of mutation detection. We present here a comparison of CCM with osmium tetroxide and with potassium permanganate, tested on a complete set of single base pair mismatches and a number of small insertion/deletions.