Yang Shuquan,Wang Yating,Li Huazheng,Zhan Yixing,Ding Xiaoqing,Wang Ming,Wang Xinlong,Xiao Leqin
p -Hydroxybenzoic acid is an emerging contaminant because it has multiple sources such as the hydrolysis of methylparaben, ethylparaben and propylparaben used widely as preservatives in food and drinks, and as well as from the agro-industrial wastewaters. In this study, the nano-ZIF-8@chitosan microspheres (ZIF-8@CSM) were fabricated via the combination of inverse emulsion method and in-situ growth method. The performance of ZIF-8@CSM for the adsorption of p -hydroxybenzoic acid from aqueous solution was studied. The adsorption kinetics showed that the adsorption rapidly reached the equilibrium about 30 s. The equilibrium data were well described by the Langmuir isothermal model and the estimated maximum adsorption capacity was 128.70 mg/g. The thermodynamics analysis indicated negative free energy, enthalpy, and entropy changes suggesting that the adsorption process was spontaneous and exothermic. ZIF-8@CSM is promising to be used as a good adsorption material to remove p -hydroxybenzoic acid rapidly from aqueous solutions.
ZhaoGuo Wu,XueZhi Zhou,Hao Chen,AiWu Zhao,Jin Wang
Controlling formation of metal organic frameworks (MOFs) with embedded enzymes on magnetic surface has been achieved by a confined growth with particle attachment driven self-sieving approach for the first time. Specifically, a versatile route of silica encapsulation guided enzyme assembly for formation of ZIF-8 shell has been successfully demonstrated by shaped-controllable Fe 3 O 4 nanoparticles , e.g., nanorod and nanocube. Interestingly, silica encapsulation can lead to structural diversity of ZIF-8 shell on the shaped-controllable Fe 3 O 4 nanoparticles for affecting properties of the nanocomposites. Furthermore, embedded enzymes confined between silica endoskeleton and ZIF-8 exoskeleton can participate in cascade reaction with different activities and stabilities in the terms of plasmonic assemblies fabrication and cancer cell catalytic therapy. As a result, a circulation plasmonic fabrication and cancer therapy can be achieved via the magnetic nanocomposites. It can be expected that the confined growth with particle attachment driven self-sieving method can be versatile to generate diverse MOFs shell encapsulated shaped-controllable nanoparticles for efficiently embedding enzyme in the nanocomposites.