Metal-organic frameworks(MOFs)have been intensely studied for the past few decades as an enormous family of highly tunable porous materials with promisingly applicable functionalities in adsorption,separation,catalysi...Metal-organic frameworks(MOFs)have been intensely studied for the past few decades as an enormous family of highly tunable porous materials with promisingly applicable functionalities in adsorption,separation,catalysis,sensing,electrochemistry,and a great number of emerging purposes.As a classic MOF,zeolitic imidazolate framework-8(ZIF-8)is conventionally one of the very few MOF members that has been commercialized with considerable production.展开更多
The feasibility of adsorption and the adsorption behavior of radon on a nanomaterial-based zeolitic imidazolate framework-8(ZIF-8) adsorbent were investigated.Grand canonical Monte Carlo simulation and four-channel lo...The feasibility of adsorption and the adsorption behavior of radon on a nanomaterial-based zeolitic imidazolate framework-8(ZIF-8) adsorbent were investigated.Grand canonical Monte Carlo simulation and four-channel low-background a/b measurement were performed to examine the adsorption kinetics of this adsorbent. Results demonstrated that ZIF-8 is a good adsorbent of radon.Therefore, this adsorbent can be used to significantly reduce the hazardous effects of radon on occupational radiation workers.展开更多
Zeolitic imidazolate framework-8(ZIF-8)with porous structure,biocompatibility,and pH-sensitive release behavior is a promising nanoplatform for protein delivery.However,it is still a challenging task for a practical s...Zeolitic imidazolate framework-8(ZIF-8)with porous structure,biocompatibility,and pH-sensitive release behavior is a promising nanoplatform for protein delivery.However,it is still a challenging task for a practical synthesis of protein-loaded ZIF-8 nanoparticles.Here we report an all-aqueous microfluidic reactor for one-step,rapid,and highly controlled synthesis of ZIF-8 nanoparticles with high protein loading at room temperature.Microfluidic reactor allows for an ultrafast(<35 ms),complete mixing of Zn2+ions and 2-methylimidazole(2-MIM)at different molecular ratios,leading to the formation of stable ZIF-8 nanoparticles with tunable sizes(13.2–191.4 nm)in less than 30 s.By pre-mixing various proteins such as bovine serum albumin(BSA)(isoelectric point(pI)=5.82),ovalbumin(OVA)(pI=4.82),or RNase A(pI=8.93)with 2-MIM,ZIF-8 nanoparticles can be synthesized with protein encapsulation efficiency over 97%.Among the nanoparticles with different sizes,25 nm ZIF-8 nanoparticles show the best performance in promoting the cellular uptake of protein payload.Using OVA as a model protein,we demonstrate that 25 nm ZIF-8 nanoparticles significantly enhance the cytosolic delivery of antigen,as indicated by the effective activation of dendritic cells.We anticipate that this microfluidic synthesis of nanomaterials may advance the emerging field of cytosolic protein delivery.展开更多
Immobilization of D-amino acid dehydrogenase(DAADH)by the assembly of peptide linker was studied for the biosynthesis of Dphenylalanine.Hybrid material of zeolitic imidazolate framework-8(ZIF-8)combined with reduced g...Immobilization of D-amino acid dehydrogenase(DAADH)by the assembly of peptide linker was studied for the biosynthesis of Dphenylalanine.Hybrid material of zeolitic imidazolate framework-8(ZIF-8)combined with reduced graphene oxide(RGO)was applied for the immobilization of DAADH from Ureibacillus thermosphaericus.The recovery rate of DAADH/ZIF-8/RGO was 165.6%.DAADH/ZIF-8/RGO remained 53.4%of its initial activity at 50°C for 10 h while the free enzyme was inactivated.DAADH/ZIF-8/RGO maintained 70.5%activity in hyperalkaline solution with pH 12.Kinetic parameters indicated that DAADH/ZIF-8/RGO had greater affinity of phenylpyruvate as V_(max)/K_(m)of DAADH/ZIF-8/RGO was 1.27-fold than free enzyme.After seven recycles,the activity of DAADH/ZIF-8/RGO remained 64.3%.Furthermore,one-step separation and in situ immobilization of DAADH by ZIF-8/RGO/Ni was carried out with 1.5-fold activity enhancement.Combining peptide linker and metal-organic framework(MOF)immobilization,thermostability and activity of the immobilized DAADH were significantly improved.展开更多
The requirement of energy-storage equipment needs to develop the lithium ion battery(LIB) with high electrochemical performance. The surface modification of commercial LiFePO_4(LFP) by utilizing zeolitic imidazolate f...The requirement of energy-storage equipment needs to develop the lithium ion battery(LIB) with high electrochemical performance. The surface modification of commercial LiFePO_4(LFP) by utilizing zeolitic imidazolate frameworks-8(ZIF-8) offers new possibilities for commercial LFP with high electrochemical performances.In this work, the carbonized ZIF-8(C_(ZIF-8)) was coated on the surface of LFP particles by the in situ growth and carbonization of ZIF-8. Transmission electron microscopy indicates that there is an approximate 10 nm coating layer with metal zinc and graphite-like carbon on the surface of LFP/C_(ZIF-8) sample. The N_2 adsorption and desorptionisotherm suggests that the coating layer has uniform and simple connecting mesopores. As cathode material, LFP/C_(ZIF-8) cathode-active material delivers a discharge specific capacity of 159.3 m Ah g^(-1) at 0.1 C and a discharge specific energy of 141.7 m Wh g^(-1) after 200 cycles at 5.0 C(the retention rate is approximate 99%). These results are attributed to the synergy improvement of the conductivity,the lithium ion diffusion coefficient, and the degree of freedom for volume change of LFP/C_(ZIF-8) cathode. This work will contribute to the improvement of the cathode materials of commercial LIB.展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51603052 and 51573216)the Fundamental Research Funds for the Central Universities(Grant Nos.18lgpy02 and 16lgjc66).
文摘Metal-organic frameworks(MOFs)have been intensely studied for the past few decades as an enormous family of highly tunable porous materials with promisingly applicable functionalities in adsorption,separation,catalysis,sensing,electrochemistry,and a great number of emerging purposes.As a classic MOF,zeolitic imidazolate framework-8(ZIF-8)is conventionally one of the very few MOF members that has been commercialized with considerable production.
基金Supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Open Project of Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection(No.KJS1246)
文摘The feasibility of adsorption and the adsorption behavior of radon on a nanomaterial-based zeolitic imidazolate framework-8(ZIF-8) adsorbent were investigated.Grand canonical Monte Carlo simulation and four-channel low-background a/b measurement were performed to examine the adsorption kinetics of this adsorbent. Results demonstrated that ZIF-8 is a good adsorbent of radon.Therefore, this adsorbent can be used to significantly reduce the hazardous effects of radon on occupational radiation workers.
基金supported by the National Key R&D Program of China(Nos.2020YFA0210800 and 2021YFA0909400)the National Natural Science Foundation of China(Nos.22025402,22227805,T2222008,and 22174030)+1 种基金The Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB36020300)CAS Project for Young Scientists in Basic Research(No.YSBR-036).
文摘Zeolitic imidazolate framework-8(ZIF-8)with porous structure,biocompatibility,and pH-sensitive release behavior is a promising nanoplatform for protein delivery.However,it is still a challenging task for a practical synthesis of protein-loaded ZIF-8 nanoparticles.Here we report an all-aqueous microfluidic reactor for one-step,rapid,and highly controlled synthesis of ZIF-8 nanoparticles with high protein loading at room temperature.Microfluidic reactor allows for an ultrafast(<35 ms),complete mixing of Zn2+ions and 2-methylimidazole(2-MIM)at different molecular ratios,leading to the formation of stable ZIF-8 nanoparticles with tunable sizes(13.2–191.4 nm)in less than 30 s.By pre-mixing various proteins such as bovine serum albumin(BSA)(isoelectric point(pI)=5.82),ovalbumin(OVA)(pI=4.82),or RNase A(pI=8.93)with 2-MIM,ZIF-8 nanoparticles can be synthesized with protein encapsulation efficiency over 97%.Among the nanoparticles with different sizes,25 nm ZIF-8 nanoparticles show the best performance in promoting the cellular uptake of protein payload.Using OVA as a model protein,we demonstrate that 25 nm ZIF-8 nanoparticles significantly enhance the cytosolic delivery of antigen,as indicated by the effective activation of dendritic cells.We anticipate that this microfluidic synthesis of nanomaterials may advance the emerging field of cytosolic protein delivery.
基金supported by the National Natural Science Foundation of China(Nos.21776233 and 22078273)National Key Research and Development Program(No.2022YFA0912000).
文摘Immobilization of D-amino acid dehydrogenase(DAADH)by the assembly of peptide linker was studied for the biosynthesis of Dphenylalanine.Hybrid material of zeolitic imidazolate framework-8(ZIF-8)combined with reduced graphene oxide(RGO)was applied for the immobilization of DAADH from Ureibacillus thermosphaericus.The recovery rate of DAADH/ZIF-8/RGO was 165.6%.DAADH/ZIF-8/RGO remained 53.4%of its initial activity at 50°C for 10 h while the free enzyme was inactivated.DAADH/ZIF-8/RGO maintained 70.5%activity in hyperalkaline solution with pH 12.Kinetic parameters indicated that DAADH/ZIF-8/RGO had greater affinity of phenylpyruvate as V_(max)/K_(m)of DAADH/ZIF-8/RGO was 1.27-fold than free enzyme.After seven recycles,the activity of DAADH/ZIF-8/RGO remained 64.3%.Furthermore,one-step separation and in situ immobilization of DAADH by ZIF-8/RGO/Ni was carried out with 1.5-fold activity enhancement.Combining peptide linker and metal-organic framework(MOF)immobilization,thermostability and activity of the immobilized DAADH were significantly improved.
基金supported by the Scientific and Technological Development Project of the Beijing Education Committee(No.KZ201710005009)
文摘The requirement of energy-storage equipment needs to develop the lithium ion battery(LIB) with high electrochemical performance. The surface modification of commercial LiFePO_4(LFP) by utilizing zeolitic imidazolate frameworks-8(ZIF-8) offers new possibilities for commercial LFP with high electrochemical performances.In this work, the carbonized ZIF-8(C_(ZIF-8)) was coated on the surface of LFP particles by the in situ growth and carbonization of ZIF-8. Transmission electron microscopy indicates that there is an approximate 10 nm coating layer with metal zinc and graphite-like carbon on the surface of LFP/C_(ZIF-8) sample. The N_2 adsorption and desorptionisotherm suggests that the coating layer has uniform and simple connecting mesopores. As cathode material, LFP/C_(ZIF-8) cathode-active material delivers a discharge specific capacity of 159.3 m Ah g^(-1) at 0.1 C and a discharge specific energy of 141.7 m Wh g^(-1) after 200 cycles at 5.0 C(the retention rate is approximate 99%). These results are attributed to the synergy improvement of the conductivity,the lithium ion diffusion coefficient, and the degree of freedom for volume change of LFP/C_(ZIF-8) cathode. This work will contribute to the improvement of the cathode materials of commercial LIB.
