The utilization of polymer/metal organic framework (MOF) nanocomposites in various biomedical applications has been widely studied due to their unique properties that arise from MOFs or hybrid ...composite systems. This review focuses on the types of polymer/MOF nanocomposites used in drug delivery and imaging applications. Initially, a comprehensive introduction to the synthesis and structure of MOFs and bio-MOFs is presented. Subsequently, the properties and the performance of polymer/MOF nanocomposites used in these applications are examined, in relation to the approach applied for their synthesis: (i) non-covalent attachment, (ii) covalent attachment, (iii) polymer coordination to metal ions, (iv) MOF encapsulation in polymers, and (v) other strategies. A critical comparison and discussion of the effectiveness of polymer/MOF nanocomposites regarding their synthesis methods and their structural characteristics is presented.
The exploration of new porous hybrid materials is of great importance because of their unique properties and promising applications in separation of materials, catalysis, etc. Herein, for the first ...time, by integration of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), a new type of MOF@COF core–shell hybrid material, i.e., NH2‐MIL‐68@TPA‐COF, with high crystallinity and hierarchical pore structure, is synthesized. As a proof‐of‐concept application, the obtained NH2‐MIL‐68@TPA‐COF hybrid material is used as an effective visible‐light‐driven photocatalyst for the degradation of rhodamine B. The synthetic strategy in this study opens up a new avenue for the construction of other MOF–COF hybrid materials, which could have various promising applications.
By integration of metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), a new type of MOF@COF core–shell hybrid material, i.e., NH2‐MIL‐68@TPA‐COF, with high crystallinity and hierarchical pore structure, is synthesized. The obtained hybrid material can be used as an effective visible‐light‐driven photocatalyst for the degradation of rhodamine B.
Air filtration has become an essential need for passive pollution control. However, most of the commercial air purifiers rely on dense fibrous filters, which have good particulate matter (PM) removal ...capability but poor biocidal effect. Here we present the photocatalytic bactericidal properties of a series of metal-organic frameworks (MOFs) and their potentials in air pollution control and personal protection. Specifically, a zinc-imidazolate MOF (ZIF-8) exhibits almost complete inactivation of Escherichia coli (E. coli) (>99.9999% inactivation efficiency) in saline within 2 h of simulated solar irradiation. Mechanistic studies indicate that photoelectrons trapped at Zn
centers within ZIF-8 via ligand to metal charge transfer (LMCT) are responsible for oxygen-reduction related reactive oxygen species (ROS) production, which is the dominant disinfection mechanism. Air filters fabricated from ZIF-8 show remarkable performance for integrated pollution control, with >99.99% photocatalytic killing efficiency against airborne bacteria in 30 min and 97% PM removal. This work may shed light on designing new porous solids with photocatalytic antibiotic capability for public health protection.
•Recent advances on MOFs/COFs/HOFs as enzyme immobilization matrixes were summarized.•Immobilization strategies and some technological hotspots of MOF as enzyme carriers were reviewed.•Applications ...of enzyme-MOF/COF/HOF composites in biosensors were discussed.•Challenges and opportunities on MOFs/COFs/HOFs as enzyme immobilization matrixes and their applications in sensing were proposed.
Enzyme immobilization in nano-space to maintain or even enhance their activity and stability is generally challenging. In recent years, metal–organic frameworks (MOFs), covalent organic frameworks (COFs) and hydrogen-bonded organic frameworks (HOFs), as new classes of exciting porous framework materials, have attracted much attention for many fascinating merits such as large specific surface area, specific porosity, stable framework structure,and diverse functional sites, which allow them to be considered as promising enzyme immobilization carriers. Compared with other traditional support materials, MOFs/COFs/HOFsas the immobilization carriers of enzymeshold higher enzyme loading capacity and can significantly improve the catalytic performance and reusability of enzymes. In this paper, we firstly discuss various strategies of using MOFs/functional MOFs as matrixes to immobilize enzymes. Then, the latest research progresses of COFs and HOFs in enzyme immobilization are systematically introduced. Subsequently, the applications of enzyme-MOF/COF/HOF biocomposites in sensing, including electrochemical, colorimetric, fluorescent and other sensing strategies are comprehensively summarized. Finally, the challenges and opportunities in this field are tentatively discussed.
Nanoparticles have become a vital part of a vast number of established processes and products; they are used as catalysts, in cosmetics, and even by the pharmaceutical industry. Despite this, ...however, the reliable and reproducible production of functional nanoparticles for specific applications remains a great challenge. In this respect, reticular chemistry provides methods for connecting molecular building blocks to nanoparticles whose chemical composition, structure, porosity, and functionality can be controlled and tuned with atomic precision. Thus, reticular chemistry allows for the translation of the green chemistry principle of atom economy to functional nanomaterials, giving rise to the multifunctional efficiency concept. This principle encourages the design of highly active nanomaterials by maximizing the number of integrated functional units while minimizing the number of inactive components. State‐of‐the‐art research on reticular nanoparticles—metal‐organic frameworks, zeolitic imidazolate frameworks, and covalent organic frameworks—is critically assessed and the beneficial features and particular challenges that set reticular chemistry apart from other nanoparticle material classes are highlighted. Reviewing the power of reticular chemistry, it is suggested that the unique possibility to efficiently and straightforwardly synthesize multifunctional nanoparticles should guide the synthesis of customized nanoparticles in the future.
The discovery of reticular chemistry has unexpectedly shifted the focus of functional nanoparticle design away from size, shape, and surface characteristics toward straightforward direct integration of functional building units into the nanomaterial. The realization of this potential together with systematic material characterization can revolutionize nanoscience to enable groundbreaking advances in different areas of the life sciences and catalysis.
A defect‐free zeolitic imidazolate framework‐8 (ZIF‐8)/graphene oxide (GO) membrane with a thickness of 100 nm was prepared using two‐dimensional (2D) ZIF‐8/GO hybrid nanosheets as seeds. Hybrid ...nanosheets with a suitable amount of ZIF‐8 nanocrystals were essential for producing a uniform seeding layer that facilitates fast crystal intergrowth during membrane formation. Moreover, the seeding layer acts as a barrier between two different synthesis solutions, and self‐limits crystal growth and effectively eliminates defects during the contra‐diffusion process. The resulting ultrathin membranes show excellent molecular sieving gas separation properties, such as with a high CO2/N2 selectivity of 7.0. This 2D nano‐hybrid seeding strategy can be readily extended to the fabrication of other defect‐free and ultrathin MOF or zeolite molecular sieving membranes for a wide range of separation applications.
Thin sieves: Zeolitic imidazolate framework‐8 (ZIF‐8)/graphene oxide (GO) membrane with a thickness of 100 nm was prepared using 2D ZIF‐8/GO hybrid nanosheets as seeds. The nanohybrid seeding facilitates uniform crystallization of ZIF‐8 on the porous substrate, and the GO promotes crystal intergrowth, leading to high‐quality molecular sieving membranes.
The
ex vivo
application of enzymes in various processes, especially
via
enzyme immobilization techniques, has been extensively studied in recent years in order to enhance the recyclability of ...enzymes, to minimize enzyme contamination in the product, and to explore novel horizons for enzymes in biomedical applications. Possessing remarkable amenability in structural design of the frameworks as well as almost unparalelled surface tunability, Metal-Organic Frameworks (MOFs) have been gaining popularity as candidates for enzyme immobilization platforms. Many MOF-enzyme composites have achieved unprecedented results, far outperforming free enzymes in many aspects. This review summarizes recent developments of MOF-enzyme composites with special emphasis on preparative techniques and the synergistic effects of enzymes and MOFs. The applications of MOF-enzyme composites, primarily in transferation, catalysis and sensing, are presented as well. The enhancement of enzymatic activity of the composites over free enzymes in biologically incompatible conditions is emphasized in many cases.
This review summarizes the syntheses and applications of metal-organic framework (MOF)-enzyme composites with specific emphasis on the merits MOFs bring to the immobilized enzymes.
Selective delivery of photosensitizers to mitochondria of cancer cells can enhance the efficacy of photodynamic therapy (PDT). Though cationic Ru-based photosensitizers accumulate in mitochondria, ...they require excitation with less penetrating short-wavelength photons, limiting their application in PDT. We recently discovered X-ray based cancer therapy by nanoscale metal-organic frameworks (nMOFs) via enhancing radiotherapy (RT) and enabling radiodynamic therapy (RDT). Herein we report Hf-DBB-Ru as a mitochondria-targeted nMOF for RT-RDT. Constructed from Ru-based photosensitizers, the cationic framework exhibits strong mitochondria-targeting property. Upon X-ray irradiation, Hf-DBB-Ru efficiently generates hydroxyl radicals from the Hf
SBUs and singlet oxygen from the DBB-Ru photosensitizers to lead to RT-RDT effects. Mitochondria-targeted RT-RDT depolarizes the mitochondrial membrane to initiate apoptosis of cancer cells, leading to significant regression of colorectal tumors in mouse models. Our work establishes an effective strategy to selectively target mitochondria with cationic nMOFs for enhanced cancer therapy via RT-RDT with low doses of deeply penetrating X-rays.
Proton conductive materials are of significant importance and highly desired for clean energy-related applications. Discovery of practical metal-organic frameworks (MOFs) with high proton conduction ...remains a challenge due to the use of toxic chemicals, inconvenient ligand preparation and complication of production at scale for the state-of-the-art candidates. Herein, we report a zirconium-MOF, MIP-202(Zr), constructed from natural α-amino acid showing a high and steady proton conductivity of 0.011 S cm
at 363 K and under 95% relative humidity. This MOF features a cost-effective, green and scalable preparation with a very high space-time yield above 7000 kg m
day
. It exhibits a good chemical stability under various conditions, including solutions of wide pH range and boiling water. Finally, a comprehensive molecular simulation was carried out to shed light on the proton conduction mechanism. All together these features make MIP-202(Zr) one of the most promising candidates to approach the commercial benchmark Nafion.
PDF
