In this study,an amine-coordinated cobalt phthalocyanine(CoPc)-based anodic catalyst was fabricated by a facile process,to enhance the performance of hydrogen peroxide fuel cells(HPFCs) and enzymatic biofuel cells(EBC...In this study,an amine-coordinated cobalt phthalocyanine(CoPc)-based anodic catalyst was fabricated by a facile process,to enhance the performance of hydrogen peroxide fuel cells(HPFCs) and enzymatic biofuel cells(EBCs).For this purpose,polyethyleneimine(PEI) was added onto the reduced graphene oxide and CoPc composite(RGO/CoPc) to create abundant NH2 axial ligand groups,for anchoring the Co core within the CoPc.Owing to the PEI addition,the onset potential of the hydrogen peroxide oxidation reaction was shifted by 0.13 V in the negative direction(0.02 V) and the current density was improved by 1.92 times(1.297 mA cm^(-2)),compared to those for RGO/CoPc(0.15 V and 0.676 mA cm^(-2),respectively),due to the formation of donor-acceptor dyads and the prevention of CoPc from leaching out.The biocatalyst using glucose oxidase(GOx)([RGO/CoPc]/PEI/GOx) showed a better onset potential and catalytic activity(0.15 V and 318.7 μA cm^(-2)) than comparable structures,as well as significantly improved operational durability and long-term stability.This is also attributed to PEI,which created a favorable microenvironment for the enzyme.The maximum power densities(MPDs) and open-circuit voltages(OCVs) obtained for HPFCs and EBCs using the suggested catalyst were 105.2±1.3 μW cm^(-2)(0.317±0.003 V) and 25.4±0.9 μW cm^(-2)(0.283±0.007 V),respectively.This shows that the amine axial ligand effectively improves the performance of the actual driving HPFCs and EBCs.展开更多
Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets...Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide(NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets via liquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications. Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.展开更多
Evolution has enabled living cells to adopt their structural and functional complexity by organizing intricate cellular compartments,such as membrane-bound and membraneless organelles(MLOs),for spatiotemporal catalysi...Evolution has enabled living cells to adopt their structural and functional complexity by organizing intricate cellular compartments,such as membrane-bound and membraneless organelles(MLOs),for spatiotemporal catalysis of physiochemical reactions essential for cell plasticity control.Emerging evidence and view support the notion that MLOs are built by multivalent interactions of biomolecules via phase separation and transition mechanisms.In healthy cells,dynamic chemical modifications regulate MLO plasticity,and reversible phase separation is essential for cell homeostasis.Emerging evidence revealed that aberrant phase separation results in numerous neurodegenerative disorders,cancer,and other diseases.In this review,we provide molecular underpinnings on(i)mechanistic understanding of phase separation,(ii)unifying structural and mechanistic principles that underlie this phenomenon,(iii)various mechanisms that are used by cells for the regulation of phase separation,and(iv)emerging therapeutic and other applications.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(Nos.2017R1D1A1B03032033 and 2020R1C1C1010386)“Leaders in INdustry-university Cooperation+”project supported by the Ministry of Education and National Research Foundation of Korea。
文摘In this study,an amine-coordinated cobalt phthalocyanine(CoPc)-based anodic catalyst was fabricated by a facile process,to enhance the performance of hydrogen peroxide fuel cells(HPFCs) and enzymatic biofuel cells(EBCs).For this purpose,polyethyleneimine(PEI) was added onto the reduced graphene oxide and CoPc composite(RGO/CoPc) to create abundant NH2 axial ligand groups,for anchoring the Co core within the CoPc.Owing to the PEI addition,the onset potential of the hydrogen peroxide oxidation reaction was shifted by 0.13 V in the negative direction(0.02 V) and the current density was improved by 1.92 times(1.297 mA cm^(-2)),compared to those for RGO/CoPc(0.15 V and 0.676 mA cm^(-2),respectively),due to the formation of donor-acceptor dyads and the prevention of CoPc from leaching out.The biocatalyst using glucose oxidase(GOx)([RGO/CoPc]/PEI/GOx) showed a better onset potential and catalytic activity(0.15 V and 318.7 μA cm^(-2)) than comparable structures,as well as significantly improved operational durability and long-term stability.This is also attributed to PEI,which created a favorable microenvironment for the enzyme.The maximum power densities(MPDs) and open-circuit voltages(OCVs) obtained for HPFCs and EBCs using the suggested catalyst were 105.2±1.3 μW cm^(-2)(0.317±0.003 V) and 25.4±0.9 μW cm^(-2)(0.283±0.007 V),respectively.This shows that the amine axial ligand effectively improves the performance of the actual driving HPFCs and EBCs.
基金supported by the National Natural Science Foundation of China(21735002,22177032,32101082)the Science Fund for Distinguished Young Scholars of Hunan Province(2021JJ10013)+1 种基金the Hunan Province Innovative Talent Funding for Postdoctoral Fellows(2021RC2059)the Postdoctoral Science Foundation of China(2021TQ0103,2021M690957).
文摘Implanting artificial organelles in living cells is capable of correcting cellular dysfunctionalities for cell repair and biomedical applications. In this work, phase-separated bienzyme-loaded coacervate microdroplets are established as a model of artificial membraneless organelles in endothelial dysfunctional cells for the cascade enzymatic production of nitric oxide(NO) with a purpose of correcting cellular NO deficiency. We prepared the coacervate microdroplets via liquid-liquid phase separation of oppositely charged polyelectrolytes, in which glucose oxidase/horseradish peroxidase-mediated cascade reaction was compartmented. After the coacervate microdroplets were implanted in NO-deficient dysfunctional cells, the compartments maintained a phase-separated liquid droplet structure, which facilitated a significant enhancement of NO production in the dysfunctional cells. The recovery of NO production was further exploited to inhibit clot formation in blood plasma located in the cell suspension. This demonstrated a proof-of-concept design of artificial organelles in dysfunctional cells for cell repair and anticoagulation-related medical applications. Our results demonstrate an approach for the construction of coacervate droplets through phase separation for the generation of artificial membraneless organelles, which can be designed to provide an array of functionalities in living organisms that have the potential to be used in the field of cell engineering and medical therapy.
基金supported in part by grants from the National Natural Science Foundation of China(32090040,31621002,21922706,81630080,31430054,91854203,91853115,and 31671405)the National Key Research and Development Program of China(2017YFA0503600 and 2016YFA0100500)+4 种基金the Ministry of Education of China(IRT_17R102)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB19000000)the Fundamental Research Funds for the Central Universities(KB2070000023 and WK2070000194)National Institutes of Health Grants(CA164133,DK115812,and DK56292)We thank our laboratory members for stimulating discussion。
文摘Evolution has enabled living cells to adopt their structural and functional complexity by organizing intricate cellular compartments,such as membrane-bound and membraneless organelles(MLOs),for spatiotemporal catalysis of physiochemical reactions essential for cell plasticity control.Emerging evidence and view support the notion that MLOs are built by multivalent interactions of biomolecules via phase separation and transition mechanisms.In healthy cells,dynamic chemical modifications regulate MLO plasticity,and reversible phase separation is essential for cell homeostasis.Emerging evidence revealed that aberrant phase separation results in numerous neurodegenerative disorders,cancer,and other diseases.In this review,we provide molecular underpinnings on(i)mechanistic understanding of phase separation,(ii)unifying structural and mechanistic principles that underlie this phenomenon,(iii)various mechanisms that are used by cells for the regulation of phase separation,and(iv)emerging therapeutic and other applications.
