The Determination of a Small Amount of Biological Constituent by the Use of Chemiluminescence. XIV. The Flow-Injection Analysis of Protein Using Ultrasonic Chemiluminescence of Luminol

Abstract

Abstract A flow-injection analysis method for the determination of a small amount of protein has been established by the use of the ultrasonic chemiluminescence of luminol. The present method was based on the phenomenon that the catalytic activity of cobalt(II) for the ultrasonic chemiluminescence of luminol decreased in the presence of protein. The apparatus consisted of only a luminol solution line equipped with an ultrasonic irradiation bath and a cobalt(II) catalyst solution line equipped with a sample inlet. Under optimum conditions, similar calibration curves were obtained for bovine serum albumin, bovine serum γ-globulin, human serum albumin, and human serum γ-globulin. According to the present method, these proteins could be determined in the concentration range 5.0×10−6–1.0×10−1 g dm−3, with a detection limit of 200 pg (injected sample volume 40 mm3, S/N=2) and a coefficient of variation of 2.9% (n=8) at a rate of about 60 samples per hour.