Resonance light scattering spectral method for the determination of serum albumin with the interaction of neutral red–sodium dodecyl sulfonate

Based on the enhancement of resonance light scattering (RLS) of serum albumin interaction with neutral red (NR) and sodium dodecyl sulfonate (SDS), a novel sensitive assay of serum albumins has been developed. Experimental conditions such as mixing sequence of reagents, pH, NR and SDS concentrations have been optimized. Linear relationships between the enhanced RLS intensity and the protein concentration were observed for bovine serum albumin (BSA) within the range of 0.01–5.0 μg mL−1 and human serum albumin (HAS) of 0.01–7.0 μg mL−1. The detection limits (S/N = 3) are 6.0 ng mL−1 for BSA and 5.0 ng mL−1 for HAS, respectively. The method was successfully applied to the determination of HSA in human blood plasma samples with recovery from 97.3 to 104.3%.