[Resonance light scattering study on interaction of solochrome cyanine R with protein and light scattering determination of trace protein].

The resonance light scattering (RLS) of Solochrome Cyanine R(SCR) is greatly enhanced by proteins. Based on this phenomenon, a novel method for the determination of protein by using SCR as a labeling agent was developed. In the pH 4.0 solution the enhanced intensity of RLS at 400 nm is proportional to the concentration of protein. The linear range for bovine serum albumin (BSA) is 0-5.0 mg x L(-1) and the limit of detection is 44.4 microg x L(-1). The method is simple, rapid, sensitive, stable, and tolerant of many foreign substances. It has been used to determine proteins in human urine samples with satisfactory results.