Quantitative Analysis of Bovine Serum α1-Acid Glycoprotein by Nepherometric Immunoassay and Turbidimetric Immunoassay

Alpha 1-acid glycoprotein (α1-AG) is a family of acute inflammatory phase proteins in serum, of which the serum α1-AG concentration in inflammatory diseased or operated bovines is much higher than that in healthy ones. The present study was conducted in order to compare fundamental analytical precision tests via nepherometric immunoasssay (NIA) and turbidimetric immunoassay (TIA) for automated analysis with the single radial immunodiffusion (SRID) method. As a result, the analytical ranges of α1-AG were 12 to 2, 500 and 20 to 2, 000, μg/ml for the NIA and TIA methods, respectively. For either method, we could not confirm the influence of any obstacles such as hemoglobin, cohesive bilirubin (C), free bilirubin (F) or ascorbic acid. However, there was a slight decrease in α1-AG values due to chyles in NIA. Linear lines drawn via decreasing optical density were observed up to 1, 200μg/ml. Simultaneous repeatability compared favorably with the coefficients of variance which were less than 2%. When the serum α1-AG concentrations collected from 48 healthy Holstein calves aged 7 to 14 days old were measured by NIA, TIA and SRID, the mean value±SD were 437.5±174.0, 419.0±154.3 and 432.8±195.2(μg/ml), respectively, demonstrating that a significant correlation showed (r=0.98) among these 3 methods.