基于罗丹明的Cu^(2+)和Cd^(2+)比色探针及光谱性能研究

Synthesis of Rhodamine-based Colorimetric Probe and Spectroscopic Studies for Cu^(2+)and Cd^(2+)

以3-甲醛基-苯并嗪-2-酮和罗丹明B酰肼为原料,经缩合反应合成一种新型比色探针RC,并利用1HNMR、13CNMR和MS对其进行结构表征。利用紫外-可见紫外光谱法研究了探针RC在乙醇溶液中的金属离子识别性能,该探针在λ=496 nm处对Cu^(2+)和Cd^(2+)发生不同程度的红移,裸眼可观察到明显的颜色变化,而且不受其他离子的干扰。通过Job-plot曲线和Benesi-Hildebrand方程计算出探针RC与Cu^(2+)和Cd^(2+)的物质的量结合比均为1∶1,结合常数K分别为6.44×105和1.17×105,并测得Cu^(2+)和Cd^(2+)的最低检测限分别为5.80×10-6mol和9.19×10-6mol。

The novel colorimetric probe RC was synthesized based on rhodamine and benzoxazinone. The structure was confirmed by1 HNMR,13CNMR and MS. RC exhibited excellent sensitivity and selectivity towards Cu2＋or Cd2＋in ethanol solution,which could not be disturbed with other metal ions. Upon addition of Cu2＋or Cd2＋,a significantred shift in absorption wavelength respectively occurred with different color changes,which could be observed with naked-eye. Job-plot curve and Benesi-Hildebrand plot confirmed that the stoichiometry ratio of probe RC with Cu2＋and Cd2＋both were 1∶ 1. The binding constant of RC with Cu2＋was 6. 44 × 10^5 and 1. 17 × 105 with Cd2＋,and the detection limit for Cu2＋and Cd2＋was 5. 80 × 10^- 6mol,9. 19 × 10^- 6mol,respectively.