Assay of reducing sugars in the nanomole range with 2,2′-bicinchoninate

The photometric assay of reducing sugars with 2,2′-bicinchoninate was improved and its conditions were optimized. Optical density is linear between 1 and 25 nmol sugar/sample, and the assay is not affected by borate, phosphate, or other buffer anions. The molar extinction coefficients produced by the standard procedure with the 12 most common monosaccharides occurring in carbohydrates and conjugated glycocompounds are listed.