Alternatives for modifying the Somogyi-Nelson method for determining reducing sugars by using their thermical possibilities

This article proposes modifying the Somogyi-Nelson method for determining reducing sugars, considering that sodium arsenate (one of its constituents) is a toxic substance which is tending to disappear from the market. The chemical principles used in the Somogyi-Nelson method for determining reducing sugars are explained, taking those protocols proposed by Hawk et al (1954), Collmer et al (1988), Castellanos (1995) and the Universidad Nacional's Chemistry Departament (adapted from Fischer's protocol [1989]) as reference. The reactions of Somogyi and Nelson's reagents are evaluated separately. The reaction between the two components and a reducing sugar is analysed and two aleternatives for modifying the method are included: the use of phosphates and that of silicates. It is proposed to substitute sodium arsenate for a phosphate in the first case and in the second for a silicate.