[Microdetermination of proteins with Titan yellow by the resonance light scattering method].

A resonance light scattering method for the determination of trace proteins was developed. In the presence of Triton X-100, proteins reacted with Titan yellow to form a combination product, resulting a significant enhancement of resonance light scattering (RLS). The deltaI(RLS) was directly proportional to the concentration of protein in the range of 0.03-0.9 microg x mL(-1), with the detection limit 17.7 ng x mL(-1) for BSA. This method was applied to the determination of the proteins in synthetic and human serum samples, and compared to the CBB method, with satisfactory results.