研究了阴离子表面活性剂十二烷基硫酸钠(SDS),阳离子染料罗丹明B,与蛋白质相互作用的共振光散射(RLS)光谱及用于蛋白质的测定。实验表明,在pH4.35的酸性介质中,SDS的共振光散射强度较小,它与蛋白质结合后,共振光散射强度能得到增强,但加入阳离子染料罗丹明B后,共振光散射强度显著增强。在λ=332.0nm处,ΔIRLS最大,并且增强的共振光散射信号与蛋白质的浓度成正比。据此建立了一种测定蛋白质的新方法,该方法灵敏度高,对HSA的检出限达到1.9ng/mL,线性范围为0.01~5.0μg/mL。用于人血清样品中蛋白质的测定,回收率为94.0%~105.5%。
A new resonance light scattering method for the determination of trace proteins was developed.The interaction of HSA with SDS and rhodamine B is characterized by enhanced resonance light scattering (RLS) spectra.In the optimal interaction condition,it is found that the enhanced RLS intensities are in proportion to the concentrations of HSA with the limit of determination of 1.9 ng/mL.The present method is successfully applied to the determination of human blood plasma samples with recoveries of 94.0%~105.5%.