Analytical Sciences

Abstract − Analytical Sciences, 16(2), 145 (2000).

Color Reaction of Aromatic Aldehyde with Serum Protein and ItsApplication to the Determination of Serum Total GlobulinConcentration
Saitama Prefectural University Junior College, Department of Medical Technology,Sannomiya, Koshigaya, Saitama 343-8540, Japan
The reaction of four aromatic aldehydes including p-dimethylaminobenzaldehyde (p-DMABA) with serum protein hasbeen studied. The aromatic aldehydes gradually reacted with serum globulin with the irradiation of a fluorescent lamp atroom temperature to form a colored product with an absorption maximum at about 520 to 635 nm with high molarabsorptivity, while only slightly reacting with serum albumin. The reaction rate increased as the intensity of lightincreased, and at about 3000 luxes the reaction completed within 45 min after the reaction started. Of the four aromaticaldehydes evaluated, the colored product of p-DMABA indicated the most excellent spectral characteristics. Based onthese results, this aromatic aldehyde was applied to the detemination of the serum total globulin concentration. Themeasurement values by the proposed method, using a gamma-globulin solution as a standard material, correlated well withthose by the method of Goldenberg and Drewes using glyoxylic acid (r = 0.983), the combined biuret-BCG method (r =0.949) and moderately with the combined biuret-cellulose acetate electrophoresis method (r = 0.899).