基于N-溴代萘亚氨基乙二酸1~B_b和1~L_a吸收带减色效应的选择性铅离子光化学传感器

Selective lead ion optochemical sensor based on hypochromic effect of 1~Bb and 1~L_a absorption bands of bromonaphthyl iminodiacetic acid

中性 pH 条件下,在β-环糊精(β-CD)水溶液中 N-溴代萘亚氨基乙二酸(BNIA)的紫外吸收光谱表现出萘基典型的吸收带,即位于232 nm 的~1B_b 带和位于286 nm 的~1L_a带。pb^(2+)离子与 BNIA 配位后,引起~1B_b带显著的减色效应,并使~1L_a 带红移,在268nm 和302 nm 处出现两个等吸收点。而其它金属离子没有影响。据此建立了选择性的 pb^(2+)离子传感器,线性范围为1.0×10^(-6)～1.0×10^(-5)mol/L(r^2=0.9937),检出限为1.0×10^(-6)～1.0×10^(-5)mol/L。

At neutral pH, absorption bands of bromonaphthyl iminodiacetic acid （BNIA） were observed at 232 nm （^1Bb band） and 286 nm （^1L, band） in β- cyclodextrin aqueous solution, displaying the typical absorption spectrum of naphthalene. The complexation of BNIA with Pb^2＋ resulted in notable hypoehromic effect of ^1Bb band and bathochromic shift of ^1La band accompanying the isobestie points at 268 nm and 302 nm. Other metals had no significant influence. Based on the hypoehromic effect, the selective Pb^2＋ sensor is constructed and linear range is 1.0×10^-6 - 1.0×10^-5 mol/L（ P =0. 993 7） ,the limit of detection of Pb^2＋ is 1.0×10^-6 mol/L.