柔性镧系金属有机骨架材料比例荧光法检测Fe^(3+)

Flexible lanthanide metal-organic frameworks for ratiometric fluorescence detection for Iron(Ⅲ)

设计了一个三羧酸柔性配体L,其可提供捕获镧系金属的亲和力及调节配体的能级,并可用于合成同时具有高稳定性和双发射特性的柔性镧系金属有机骨架(Eu-MOF)材料。利用柔性配体到金属的不完全能量转移使得材料出现350 nm和623 nm处的强双发射,构筑了比例荧光传感平台。由于柔性配体不稳定的电子构型以及Eu^(3+)和Fe^(3+)之间的离子交换,Eu-MOF可用于对Fe^(3+)的比例荧光检测。Eu-MOF对Fe^(3+)的检出限为0.592μmol/L,并分别在1.0~60.0μmol/L和60.0~90.0μmol/L范围内呈线性关系,响应时间低至3 min。Eu-MOF对Fe^(3+)检测具有良好的选择性、抗干扰性以及可回收性,用于实际样品中Fe^(3+)检测,加标回收率为98.4%~102.6%。

A tricarboxylic acid flexible ligand L was designed,which not only provided affinity to capture lanthanide metals,but also modulated the energy level of the ligand,to synthesize flexible lanthanide metalorganic framework(Eu-MOF)with high stability and dual emission.The two fluorescence emission peaks of EuMOF at 350 nm and 623 nm came from the incomplete energy transfer from the flexible ligand to the metal,and a ratiometric fluorescence sensing platform was constructed.Due to the unstable electronic configuration of the flexible ligand and the ion exchange between Eu^(3+)and Fe^(3+),Eu-MOF could be used for the detection of Fe^(3+).The detection limit of Fe^(3+)was 0.592μmol/L and the linear relationships were in the ranges of 1.0-60.0μmol/L and 60.0-90.0μmol/L.The response time was about 3 min.The synthesized Eu-MOF has good selectivity,antiinterference and recyclability,and can be used for the detection of Fe^(3+)in real samples,with the recoveries of 98.4%-102.6%.