Rayleigh light scattering enhancing reaction of dibromochloroarsenazo and proteins system and its analytical application

Based on the enhancement effects of Rayleigh light scattering (RLS) on Arsenazo-DBC, a novel quantitative method for the determination of proteins in aqueous solutions has been proposed. The reaction of Dibromochloroarsenazo (Arsenazo-DBC) and five proteins (BSA, HSA, egg albumin, human gamma -IgG, Lysozyme) has been studied. Under optimal conditions the dynamic ranges for proteins were 2.5-60.0 mug(.)ml(-1), and the detection limits for HSA and BSA were at 98.50 ng(.)ml(-1) and 88.10 ng(.)ml(-1), respectively. Comparing with other methods, the method is simple, practical and relatively free from interference from coexisting substances. The method was employed for the determination of total protein in human serum with satisfactory results.