Sensitive Determination Of Protein Based On The Fluorescence Enhancement Effect Of Terbium (Iii)-Epinephrine-Protein-Sodium Dodecylsulfate System

It was found that the fluorescence of Tb3+-epinephrine (E) complex can be enhanced by both bovine serum albumin (BSA) and sodium dodecylsulfate (SDS), and stabilized by ascorbic acid (AA). It is considered that the fluorescence enhancement of the Tb3+-E-BSA-AA-SDS system originates not only from the hydrophobic microenvironment provided by BSA-SDS, but also from the energy transfer from BSA to Tb3+ in this system. Therefore, a new fluorescence method for the determination of protein concentrations as low as 1.3 x 10(-9) g mL(-1) BSA is established using Tb3+-epinephrine complex as probe. The method has been applied for the determination of BSA and human serum albumin in actual samples, and the results obtained are satisfactory. Compared with other fluorescence methods, this method is simpler and more sensitive for the determination of protein. The mechanism of the fluorescence enhancement of the system is studied in detail. Copyright (C) 2009 John Wiley & Sons, Ltd.