Mondal Partha Pratim, Palakkal Athulya S, Neogi Subhadip
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
Inorganic Materials & Catalysis Division, CSIR-Central Salt & Marine Chemicals Research Institute (CSMCRI), Bhavnagar, Gujarat, 364002, India.
Small. 2025 Jul;21(27):e2501941. doi: 10.1002/smll.202501941. Epub 2025 Apr 27.
A mixed-ligand-based novel 3D Cd(II)-based metal-organic framework (MOF) is devised from π-electron-rich organic struts that shows two-fold interpenetrated bilayer-pillar structure. The strong luminescence of the MOF gets remarkably quenched by roxarsone (ROX) organo-arsenic in water. The material further exemplifies one-of-a-kind fluoro-switchable probe for antibiotics and exhibits massive turn-off emission by tetracycline (TTC), whereas sulfamethazine (SMZ) triggers an unprecedented 120% emission enhancement. Apart from regenerative, fast-responsive, and selective fluoro-detection of all three feed-additives, particularly significant is nanomolar limits of detection (LOD) of ROX (48.9 nm), whereas LOD for SMZ (33.9 nm) ranks lowest, and that of TTC (22.8 nm) stands second lowest among reported sensory MOFs. Besides varying degrees of energy transfer contribution for turn-off detection by ROX and TTC, density functional theory calculations manifest changes in MOF energy levels by individual organo-aromatics and additionally describe framework-analyte supramolecular interactions. The MOF sensor works equally well in different wastewater specimens and a wide pH range with good recovery percentage. To broaden the practical scope of the material, cheap MOF@paper strip as well as reconfigurable MOF@chitosan@paper bio-composite is developed and successfully employed for the instantaneous turn-off detection of ROX and fluoro-switchable monitoring of both the antibiotics at their low concentrations.
一种基于混合配体的新型三维镉（II）基金属有机框架（MOF）由富含π电子的有机支柱构建而成，呈现出双重互穿的双层柱状结构。该MOF在水中的强发光被洛克沙胂（ROX）有机砷显著猝灭。该材料还例证了一种独一无二的抗生素氟可切换探针，对四环素（TTC）呈现大量的猝灭发射，而磺胺二甲嘧啶（SMZ）则引发了前所未有的120%的发射增强。除了对所有三种饲料添加剂进行可再生、快速响应和选择性的荧光检测外，特别显著的是ROX的纳摩尔检测限（LOD）为48.9 nM，而SMZ的LOD（33.9 nM）是已报道的传感MOF中最低的，TTC的LOD（22.8 nM）则排第二低。除了ROX和TTC的猝灭检测有不同程度的能量转移贡献外，密度泛函理论计算表明单个有机芳烃会使MOF能级发生变化，并额外描述了框架-分析物超分子相互作用。该MOF传感器在不同的废水样本和较宽的pH范围内均能良好工作，回收率高。为了拓宽该材料的实际应用范围，开发了廉价的MOF@纸条以及可重构的MOF@壳聚糖@纸生物复合材料，并成功用于ROX的即时猝灭检测以及两种抗生素在低浓度下的荧光可切换监测。
