[Hg(SCN)4]2-与蛋白质相互作用的共振瑞利散射光谱及其分析应用

在pH 1.0~4.5 的稀硫酸介质中, Hg(SCN)₄]^2-配阴离子与人血清白蛋白(HSA)、α-糜蛋白 酶(α-Chy)、牛血清白蛋白(BSA)、溶菌酶(Lyso)和γ-球蛋白(γ-G)等蛋白质反应形成复合物, 此 时将导致共振瑞利散射(RRS)的显著增强, 也能引起吸收光谱的变化和荧光猝灭, 同时还观察 到圆二色(CD)光谱特征的改变. 本文主要研究Hg(SCN)₄]^2-蛋白质复合物的RRS 光谱特征、适 宜的反应条件和影响因素, 以及分析化学性质, 并以Hg(SCN)₄]^2-Lyso 体系为例, 结合吸收、荧 光和圆二色光谱的变化, 对复合物的结合位点、结合模式以及散射增强的原因进行了讨论. RRS 法具有较高的灵敏度, 它对不同蛋白质的检出限在4.6~10.8 ng/mL 之间, 据此建立了 以Hg(SCN)₄]^2-配阴离子作探针测定人血液和尿液中蛋白质的新方法.

The interaction between [Hg(SCN)_4]~(2-) and proteins by resonance Rayleigh scattering spectra and their analytical applications

Hg(SCN)₄]^2- in H₂SO₄ at pH 1.0-4.5 was reacted with proteins, including human serum albumin (HSA), α-chymotrypsin (α-Chy), bovine serum albumin (BSA), lysozyme (Lyso) and γ-globin (γ-G), to form complexes. As a result, the intensities of resonance Rayleigh scattering (RRS) were significantly enhanced. Changes in absorption, circular dichroism (CD) spectra and the fluorescence quenching of proteins were also observed. Attention was paid mainly to the RRS spectral characteristics of these complexes, suitable reaction conditions, influencing factors and a number of analytical properties. The changes in absorption, fluorescence and CD spectra for the Hg(SCN)₄]^2-Lyso system were used as an example to explore the binding sites, binding model and reasons for enhanced scattering. The RRS method had a high sensitivity and the detection limits (3σ) were 4.6 - 10.8 ng/mL for the proteins studied. A new method is thus established herein, using Hg(SCN)₄]^2- as a probe for the determination of proteins in human serum and urine samples.