罗丹明Schiff碱型比色探针的合成及对Cu^(2+)的识别

Synthesis of a Novel Rhodamine Schiff Base-based Colorimetric Probe and Recognition Properties for Cu^(2+)

以7-羟基-4-甲基-8-香豆素醛和罗丹明B酰肼为原料,经缩合反应得到可选择性识别Cu2+的比色探针L,并利用1HNMR、MS和元素分析对其结构进行了表征。通过紫外-可见光谱法研究了探针L在缓冲液(V(CH3CN)∶V(Tris-HCl)=1∶1,pH=6.0)中对金属离子的识别能力。随着Cu2+加入,探针L在λ=557 nm处产生强的可见吸收响应,溶液由无色迅速转变为紫红色。在0.6×10-6~1.6×10-6mol/L范围内,Cu2+的浓度与吸光度呈线性关系,最低检测限为6.6×10-8mol/L。探针L与Cu2+形成1∶1型配合物,识别过程可逆。

A novel Cu^2＋ colorimetric probe L was synthesized by condensation reaction of rhodamine B hydrazide and 8-For- myl-7-hydroxy-4-methylcoumarin, and its structure was confirmedby 1HNMR, MS spectra and elemental analysis. The recognition properties of L with metal ions have been investigated in V（ CH3 CN ） ： V（Tris-HCl） = 1 ： 1, pH = 6. 0 solution by the UV-Vis spectrophotometry. Upon addition of Cu^2＋ into the colorless solution of probe L, a new strong absorption band centered at 557 nm was formed accompanied with a color change from colorless to purple. When the concentration of Cu^2＋ was in the range of 0. 6 × 10 ^-6 - 1.6 ×10^-6 moL/L, there was a good linearity between the absorption intensity of the probe L and the concentration of Cu^2 ＋ . The detection limit was calculated to be 6.6 × 10^-8 mol/L. The interaction of Cu^2＋ and probe Lwas proven to adopt a 1：1 binding stoichiometry and the recognition process was reversible.