Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
Key Laboratory of Materials Physics, Centre for Environmental and Energy Nanomaterials, Anhui Key Laboratory of Nanomaterials and Nanotechnology, Institute of Solid State Physics, HFIPS, Chinese Academy of Sciences, Hefei 230031, China.
Biosensors (Basel). 2022 Oct 27;12(11):935. doi: 10.3390/bios12110935.
Bifunctional luminescence metal-organic frameworks with unique nanostructures have drawn ongoing attention for simultaneous determination and elimination of metal ions in the aqueous environment, but still remain a great challenge. In this work, three-dimensional hierarchical titanium metal-organic framework (Ti-MOF) microflowers were developed by a secondary hydrothermal method for not only highly sensitive and selective detection of Al(III), but also simultaneously efficient decontamination. The resulting Ti-MOF microflowers with a diameter of 5-6 μm consisted of nanorods with a diameter of ∼200 nm and a length of 1-2 μm, which provide abundant, surface active sites for determination and elimination of Al(III) ions. Because of their substantial specific surface area and superior fluorescence characteristics, Ti-MOF microflowers are used as fluorescence probes for quantitative determination of Al(III) in the aqueous environment. Importantly, the specific FL enhancement by Al(III) via a chelation-enhanced fluorescence mechanism can be utilized for selective and quantitative determination of Al(III). The Al(III) detection has a linear range of 0.4-15 µM and a detection limit as low as 75 nM. By introducing ascorbic acid, interference of Fe(III) can be avoided to achieve selective detection of Al(III) under various co-existing cations. It is noteworthy that the Ti-MOF microflowers exhibit excellent adsorption capacity for Al(III) with a high adsorption capacity of 25.85 mg g. The rapid adsorption rate is consistent with a pseudo-second order kinetic model. Ti-MOF is a promising contender as an adsorbent and a fluorescent chemical sensor for simultaneous determination and elimination of Al(III) due to its exceptional water stability, high porosity, and intense luminescence.
具有独特纳米结构的双功能发光金属-有机骨架因其能够同时在水环境中测定和去除金属离子而受到持续关注，但这仍然是一个巨大的挑战。在这项工作中，通过二次水热法开发了三维分级钛金属-有机骨架（Ti-MOF）微花，不仅对 Al(III) 具有高灵敏度和选择性检测，而且同时具有高效的净化能力。所得 Ti-MOF 微花的直径为 5-6μm，由直径约为 200nm、长度为 1-2μm 的纳米棒组成，为 Al(III) 离子的测定和去除提供了丰富的、表面活性的位点。由于其较大的比表面积和优越的荧光特性，Ti-MOF 微花被用作荧光探针，用于在水环境中定量测定 Al(III)。重要的是，通过螯合增强荧光机制，Al(III)的特异性 FL 增强可用于 Al(III)的选择性和定量测定。Al(III)的检测线性范围为 0.4-15µM，检测限低至 75 nM。通过引入抗坏血酸，可以避免 Fe(III)的干扰，从而在各种共存阳离子下实现 Al(III)的选择性检测。值得注意的是，Ti-MOF 微花对 Al(III)具有出色的吸附能力，吸附容量高达 25.85mg g。快速的吸附速率符合准二级动力学模型。Ti-MOF 由于其出色的水稳定性、高孔隙率和强烈的发光，有望成为同时测定和去除 Al(III)的吸附剂和荧光化学传感器。
