[Fe（C2O4）3]3-与BSA相互作用的光谱特性及其分析应用

The Spectral Properties of Interaction between [Fe（C2O4）3]3- and BSA and Its Analytical Application

Fe3+在配位键作用下与草酸根离子(C2O42-)形成较稳定的配离子[Fe(C2O4)3]^3-.当以pH 4.5的NaAc-HCl缓冲溶液作为反应介质时,牛血清白蛋白(BSA)主要以正电荷形式存在,在静电引力和疏水力的作用下其与配离子[Fe(C2O4)3]^3-形成离子缔合物.以280nm为激发波长,[Fe(C2O4)3]^3-配离子无明显的荧光信号,而其与BSA形成的离子缔合物在339nm处产生1个较明显的荧光峰.在优化实验条件下,在0.10~40μg/mL范围内,体系的荧光强度变化值△F与BSA浓度之间呈现良好的线性关系,其检出限为94.3ng/mL.此方法可用于人血清样中蛋白质含量的测定.

Under the action of coordination bond,Fe3+ can coordinate with C2O42- to form a stable complex ions [Fe(C2O4)3]^3-.when the pH 4.5 Walpole buffer solution is used as the reaction medium,bovine serum albumin(BSA)primarily exists in the form of positive charges and reacts with [Fe(C2O4)3]^3- to produce an ion-association complex under the effect of electrostatic attraction and hydrophobic force.Excited with the excitation wavelength at 280 nm,the coordination ions of [Fe(C2O4)3]^3-are found to have no obvious fluorescence signal,while the ion-association complex produced by [Fe(C2O4)3]^3-and BSA is observed an obvious fluorescence peak at 339 nm.Under the optimal conditions,there exists a rather good linear relationship between the change value(ΔF)and BSA concentration in the range of 0.1~40μg/mL with the detection limit of 0.0943 ng/mL.The method can be used for the determination of protein content in human serum.