基于水分散纳米无定形水杨酸甲酯铽配合物的三价铬离子高灵敏荧光传感器（英文）

Highly Sensitive Luminescent Sensor for Cr(Ⅲ) Based on a Water Dispersed Nano-sized Amorphous Methyl Salicylate Terbium Complex

为扩大稀土荧光配合物的应用范围,满足水溶液中微量铬的高灵敏高选择性探测要求,制备了一种基于水分散纳米无定形水杨酸甲酯铽配合物(A-MS-Tb)的高灵敏三价铬离子荧光传感器。结果表明:在水溶液中直接反应合成的配合物A-MS-Tb为无定形的纳米沉淀,其粒子尺度在50~100 nm之间,具有与报道的配合物晶体类似的组成。该配合物在494、549、591和625 nm处呈现出强的荧光发射,归属于铽离子的5D4→7FJ (J=6,5,4,3)能级跃迁。A-MS-Tb与晶体配合物的显著差别在于其在水中的悬浮稳定性和荧光稳定性更好,这对于其作为荧光材料和离子传感器非常重要。尤其突出的是,当将三价铬离子加入到它的水悬浮溶液中后,会减弱配体与铽离子之间的配位作用,导致其绿色荧光被淬灭。据此,构建了一种高灵敏测定溶液中铬离子浓度的荧光探针,并对其分析的选择性、灵敏度和抗干扰能力进行了评价。

To expand the application fields of rare earth fluorescence complexes,and meet the requirements of high sensitivity and selectivity for the detection of trace chromium in aqueous solution,we prepared a sensitive luminescence sensor for Cr^3+ ion based on a water dispersed nano-sized amorphous luminescence terbium complex with methyl salicylate (A-MS-Tb).It was found that the synthesized A-MS-Tb is an amorphous precipitation with particle size ranging from 50 to 100 nm and similar composition to the reported crystalline MS-Tb(C-MS-Tb).A-MS-Tb showed strong green luminescence at 494,549,591,625 nm,which belongs to the energy level transition of 5D4→7FJ (J=6,5,4,3) of Tb^3+,respectively.The difference between A-MS-Tb and the reported C-MS-Tb lies in the stability and dispersion performance towards water which is very important for expanding its application as materials and sensors.In particularly,with the addition of Cr^3+ into the water suspension of A-MS-Tb,the coordination between the ligand and Tb^3+ is weakened,causing its green fluorescence to be quenched.Therefore,a highly sensitive sensor for detecting Cr^3+ was established,and the sensitivity,selectivity and anti-interference ability was evaluated.