College of Chemistry and Materials Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, 189 Jiuhua Southern Road, Wuhu, 241002, PR China; College of Chemistry and Materials Engineering, Chaohu University, Bantang Road, Chaohu, 238000, PR China.
College of Chemistry and Materials Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Key Laboratory of Functional Molecular Solids, Anhui Normal University, 189 Jiuhua Southern Road, Wuhu, 241002, PR China.
Talanta. 2021 Jan 1;221:121421. doi: 10.1016/j.talanta.2020.121421. Epub 2020 Jul 19.
Two-dimensional Cd-MOF/Tb (Cd-MOF = [Cd (μ-2,3-pdc) (HO)] (2,3-pdc = 2,3-pyridine dicarboxylic acid)) fluorescent nanosheets with the thickness of 1.4 nm were successfully synthesized by a simple solution route with subsequent ultrasonic exfoliation at room temperature. It was found that as-obtained Cd-MOF/Tb ultrathin nanosheets could be homogeneously dispersed in aqueous system to form a sol with excellent stability. Also, the fluorescence intensity of nanosheets remarkably increased to almost 12 times higher than that of Cd-MOF/Tb microsheets before exfoliation. Further investigations uncovered that the above strong fluorescence of Cd-MOF/Tb nanosheets could be highly sensitively quenched by Cefixime antibiotic in aqueous solution without interference from other antibiotics, amino acids and pesticides. Hence, the as-obtained ultrathin Cd-MOF/Tb nanosheets could be prepared as a highly selective and sensitive fluorescence probe for the detection of Cefixime in aqueous system. Compared with the bulk Cd-MOF/Tb sensor, the Cd-MOF/Tb ultrathin nanosheets sensor exhibited a far lower detection limit down to 26.7 nM for CFX. Also, the as-obtained nanosheets sensor presented satisfactory recovery ranging from 98.07% to 103.01% and acceptable repeatability (RSD < 6.29%, n = 6) for the detection of CFX in domestic water. Furthermore, the sensing mechanism studies revealed that the high selection of the present fluorescent probe for detection of CFX should be attributed to the cooperation of the photoinduced electron transfer and the inner filter effect.
二维 Cd-MOF/Tb（Cd-MOF=[Cd(μ-2,3-pdc)(HO)]（2,3-pdc=2,3-吡啶二甲酸））荧光纳米片，厚度为 1.4nm，通过简单的溶液路线合成，随后在室温下进行超声剥离。结果发现，所获得的 Cd-MOF/Tb 超薄纳米片可以均匀分散在水相中，形成具有优异稳定性的溶胶。此外，纳米片的荧光强度显著提高，几乎比剥离前的 Cd-MOF/Tb 微片高 12 倍。进一步的研究表明，上述 Cd-MOF/Tb 纳米片的强荧光可以在水溶液中被头孢克肟抗生素高度灵敏地猝灭，而不受其他抗生素、氨基酸和农药的干扰。因此，所获得的超薄 Cd-MOF/Tb 纳米片可以作为一种高选择性和高灵敏度的荧光探针，用于检测水溶液中的头孢克肟。与块状 Cd-MOF/Tb 传感器相比，Cd-MOF/Tb 超薄纳米片传感器对 CFX 的检测下限低至 26.7nM。此外，所获得的纳米片传感器对自来水中 CFX 的检测表现出令人满意的回收率，范围为 98.07%至 103.01%，并且重复性良好（RSD<6.29%，n=6）。此外，传感机制研究表明，本荧光探针对 CFX 检测的高选择性应归因于光诱导电子转移和内滤效应的协同作用。
