Reagent system for the spectrophotometric determination of methanol in environmental and biological samples

Abstract

A sensitive, indirect spectrophotometric method is described for the determination of methanol. Methanol is oxidised with acidic potassium permanganate to formaldehyde and is subsequently determined using p-nitroaniline and sulphur dioxide. The colour is developed in an acidic medium. Beer's law is obeyed in the range 2–10 p.p.m. The yellow dye formed is measured at 395 nm. The optimum reaction conditions and other analytical parameters have been studied. The method has been tested for the determination of methanol in water, air and biological fluids.