Pyrazolate-based materials are an important category of MOFs with robust coordinative bonds and high porosity, which possess potential advantages for uranium adsorption. However, the preparation still faces the challenges of low energy-consuming and scalable synthesis. Herein, for the first time, we demonstrated the rapid synthesis of pyrazolate-based MOFs (NiBDP-γ) by γ-irradiation induced preparation strategy and applied them to uranium adsorption. The NiBDP-γ samples can be achieved at decagram scale within minutes at room temperature and even in open-air condition. It is revealed that the high-energy γ-rays can also induce structure defects during the irradiation process, resulting in the generation of additional –NH- and –OH sites. At the optimally irradiation dose, the defective NiBDP-γ accompanied with –NH- and –OH sites show a faster removal rate and enhanced adsorption capability for U(VI). The maximum adsorption capacity for the uranium of NiBDP-γ can reach 430.8 mg/g at pH = 5 and 298 K. Kinetic adsorption results demonstrate that the introduction of defects leads to a transformation from physical adsorption to being primarily dominated by chemical adsorption. DFT calculations reveals a thermodynamically favorable binding of –NH- and –OH ligands with uranyl ions. This work offers a general approach for scalable synthesis of the pyrazolate-based MOFs and presents a novel attempt for the future application of pyrazolate-based MOFs in the treatment of uranium-containing wastewater.
Kun Zeng,Fu-xing Lin,Juan Xie,Mo-zhen Wang,Jie-lin Rong,Yu Zhao,Ye-zi You,Anila Asif,Xue-wu Ge
The development of gene carriers with high delivery efficiency and enough biosafety to replace the current viral vectors and cationic liposomes has long been a key project to achieve the practical application of gene therapy. As an abundant natural polymer, chitosan (CS) possesses incomparably high biocompatibility. However, when it is used as a gene carrier, the gene transfection efficiency is rather disappointing. Herein, we prepared a novel chitosan derivative, poly(tributyl-(4-vinylbenzyl)phosphonium)-grafted CS (CS-P), via γ-ray radiation-induced grafting copolymerization of tributyl-(4-vinylbenzyl)phosphonium in an acidic solution of CS. The CS-P could combine with pEGFP through a complex coacervation method to form pEGFP-loaded CS-P complex particles with a size of about 150 nm and a high positive zeta potential of 41.7 ± 6.1 mV. Agarose gel electrophoresis and an MTT assay show that the pEGFP-loaded CS-P particles have excellent biosafety, superior to pEGFP-loaded unmodified CS particles. In vitro and in vivo gene transfection experiments based on HeLa cells confirmed that pEGFP loaded into CS-P particles exhibits much higher gene transfection efficiency than that loaded into unmodified CS. This work provides not only a new way to modify CS with quaternary phosphonium, but also a useful and feasible way to obtain new CS-based gene vectors with high gene transfection efficiency and biosafety for potentially practical clinic applications.
危险品化学品经营许可证（带存储）