Colorimetric method for determination of ethanol in presence of methanol.
A method is described for the determination of ethanol in the presence of methanol without pre-separation. The sample is oxidized to give acetaldehyde and formaldehyde. 2-Thiobarbituric acid reagent is added and selectively forms a pink adduct with acetaldehyde, but not with formaldehyde. The method is sensitive, obeys Beer's law in the concentration range 18-80 microgram/mL, and has an advantage over other methods because it does not detect any "apparent normal value" of alcohol in blood.
D000434:Alcoholic Beverages / Q000032:analysis; D000447:Aldehydes / Q000138:chemical synthesis; D001826:Body Fluids / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D003124:Colorimetry / Q000379:methods; D000431:Ethanol / Q000032:analysis*; D006801:Humans; D000432:Methanol / Q000032:analysis*; D013270:Stomach / Q000032:analysis
D000447:Aldehydes; D000431:Ethanol; D000432:Methanol