Flexible metal–organic frameworks for the wavelength-based luminescence sensing of aqueous pH

Metal-organic frameworks (MOFs) are based on metals and organic linkers; they possess large surface areas, suitable pore size and shape, wide range of chemical composition, and functionalized pore surface, which enable them for possible applications as delivery vehicles for therapeutic agents. The challenges include not only the development of new solids but also continuous improvements in the formulation and processing of the materials, including modifying the morphology and shape of the frameworks to fit the proposed applications of drug delivery. This chapter discussed enormous MOF-based stimuli responsive drug delivery systems, and considerable achievements have been made as a new avenue for drug delivery, their structural aspects, their applications in the controlled release of the drugs, and future view for development of drug controlled release researches using MOFs. Among the properties that must be developed and approved are the materials' toxicology, stability, their reproducibility of manufacture of MOFs in body's liquid, and pharmacokinetics of drug-loaded MOFs.

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Frustrated Flexibility in Metal-Organic Frameworks

10.26434/chemrxiv.13286312 ◽

2020 ◽

Author(s):

Roman Pallach ◽

Julian Keupp ◽

Kai Terlinden ◽

Louis Frentzel-Beyme ◽

Marvin Kloß ◽

...

Keyword(s):

Metal Organic Frameworks ◽

Stimuli Responsive ◽

Dispersion Energy ◽

Materials Research ◽

Geometrical Constraints ◽

Metal Organic ◽

Flexible Metal ◽

Reversible Loss ◽

Alkoxy Groups ◽

Global And Local

<div><div><div><p>Stimuli-responsive flexible metal-organic frameworks (MOFs) remain at the forefront of porous materials research due to their enormous potential for various technological applications. Here, we introduce the concept of frustrated flexibility in MOFs, which arises from an incompatibility of intra-framework dispersion forces with the geometrical constraints of the inorganic building units. Controlled by appropriate linker functionalization with dispersion energy donating alkoxy groups, this approach results in a series of MOFs exhibiting a new type of guest- and temperature-responsive structural flexibility characterized by reversible loss and recovery of crystalline order under full retention of framework connectivity and topology. The stimuli-dependent phase change of the frustrated MOFs involves non-correlated deformations of their inorganic building unit, as probed by a combination of global and local structure techniques together with computer simulations. Frustrated flexibility may be a common phenomenon in MOF structures, which are commonly regarded as rigid, and thus may be of crucial importance for the performance of these materials in various applications.</p></div></div></div>

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Structural and dynamic studies of substrate binding in porous metal–organic frameworks

Chemical Society Reviews ◽

10.1039/c6cs00603e ◽

2017 ◽

Vol 46 (1) ◽

pp. 239-274 ◽

Cited By ~ 121

Author(s):

Timothy L. Easun ◽

Florian Moreau ◽

Yong Yan ◽

Sihai Yang ◽

Martin Schröder

Keyword(s):

Small Molecules ◽

Gas Adsorption ◽

Specific Binding ◽

Metal Organic Frameworks ◽

Porous Metal ◽

High Porosity ◽

Considerable Research ◽

Wide Range ◽

Metal Organic ◽

The Subject

Porous metal–organic frameworks (MOFs) are the subject of considerable research interest because of their high porosity and capability of specific binding to small molecules, thus underpinning a wide range of materials functions such as gas adsorption, separation, drug delivery, catalysis, and sensing.

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Frustrated Flexibility in Metal-Organic Frameworks

10.26434/chemrxiv.13286312.v1 ◽

2020 ◽

Author(s):

Roman Pallach ◽

Julian Keupp ◽

Kai Terlinden ◽

Louis Frentzel-Beyme ◽

Marvin Kloß ◽

...

Keyword(s):

Metal Organic Frameworks ◽

Stimuli Responsive ◽

Dispersion Energy ◽

Materials Research ◽

Geometrical Constraints ◽

Metal Organic ◽

Flexible Metal ◽

Reversible Loss ◽

Alkoxy Groups ◽

Global And Local

<div><div><div><p>Stimuli-responsive flexible metal-organic frameworks (MOFs) remain at the forefront of porous materials research due to their enormous potential for various technological applications. Here, we introduce the concept of frustrated flexibility in MOFs, which arises from an incompatibility of intra-framework dispersion forces with the geometrical constraints of the inorganic building units. Controlled by appropriate linker functionalization with dispersion energy donating alkoxy groups, this approach results in a series of MOFs exhibiting a new type of guest- and temperature-responsive structural flexibility characterized by reversible loss and recovery of crystalline order under full retention of framework connectivity and topology. The stimuli-dependent phase change of the frustrated MOFs involves non-correlated deformations of their inorganic building unit, as probed by a combination of global and local structure techniques together with computer simulations. Frustrated flexibility may be a common phenomenon in MOF structures, which are commonly regarded as rigid, and thus may be of crucial importance for the performance of these materials in various applications.</p></div></div></div>

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Controllable Synthesis of Metal-Organic Framework/Polyethersulfone Composites

Crystals ◽

10.3390/cryst10010039 ◽

2020 ◽

Vol 10 (1) ◽

pp. 39

Author(s):

Xiaomin Guo ◽

Bin Zheng ◽

Jinlei Wang

Keyword(s):

Composite Materials ◽

Structural Integrity ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Vital Role ◽

Particle Sizes ◽

High Porosity ◽

Controllable Synthesis ◽

Wide Range ◽

Metal Organic

Composite materials that contain metal-organic frameworks (MOFs) as a filler and a polymer matrix have attracted attention because they present a combination of high porosity and structural integrity. Phase compatibilities of the MOF and polymer play a vital role in the formation of the composites. In particular, the stiff polymer cannot easily adapt to penetrate into the surface pore of MOF and mainly depends on chemical attractions to form the MOF/polymer composites. We report the synthesis of MOF/polyethersulfone (Young’s modulus = ~2.6 GPa) via different fabrication methods, different MOF types and particle sizes, and different solvents. The formed network structures are robust, monolithic composites with 60% MOF loadings; also, the MOF surface area and porosity were fully preserved. The study explored the formation of the composite between MOF and a stiff polymer and encourages the design of more MOF/polymer composite materials across a wide range of applications.

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Biomedical Applications of Metal−Organic Frameworks for Disease Diagnosis and Drug Delivery: A Review

Nanomaterials ◽

10.3390/nano12020277 ◽

2022 ◽

Vol 12 (2) ◽

pp. 277

Author(s):

Miral Al Sharabati ◽

Rana Sabouni ◽

Ghaleb A. Husseini

Keyword(s):

Drug Delivery ◽

Biomedical Applications ◽

Chemical Engineering ◽

Metal Organic Frameworks ◽

Disease Diagnosis ◽

Inorganic Materials ◽

Synthesis Methods ◽

High Porosity ◽

Wide Range ◽

Metal Organic

Metal−organic frameworks (MOFs) are a novel class of porous hybrid organic−inorganic materials that have attracted increasing attention over the past decade. MOFs can be used in chemical engineering, materials science, and chemistry applications. Recently, these structures have been thoroughly studied as promising platforms for biomedical applications. Due to their unique physical and chemical properties, they are regarded as promising candidates for disease diagnosis and drug delivery. Their well-defined structure, high porosity, tunable frameworks, wide range of pore shapes, ultrahigh surface area, relatively low toxicity, and easy chemical functionalization have made them the focus of extensive research. This review highlights the up-to-date progress of MOFs as potential platforms for disease diagnosis and drug delivery for a wide range of diseases such as cancer, diabetes, neurological disorders, and ocular diseases. A brief description of the synthesis methods of MOFs is first presented. Various examples of MOF-based sensors and DDSs are introduced for the different diseases. Finally, the challenges and perspectives are discussed to provide context for the future development of MOFs as efficient platforms for disease diagnosis and drug delivery systems.

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Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

10.26434/chemrxiv.13146278.v1 ◽

2020 ◽

Author(s):

Pia Vervoorts ◽

Stefan Burger ◽

Karina Hemmer ◽

Gregor Kieslich

Keyword(s):

High Pressure ◽

State Of The Art ◽

Energy Landscape ◽

Structural Flexibility ◽

Zeolitic Imidazolate Frameworks ◽

Stimuli Responsive ◽

X Ray Diffraction ◽

X Ray ◽

Open Questions ◽

Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to <i>p</i> = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at <i>p</i> = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).<br>

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Revisiting the High-Pressure Properties of the Metal-Organic Frameworks ZIF-8 and ZIF-67

10.26434/chemrxiv.13146278 ◽

2020 ◽

Author(s):

Pia Vervoorts ◽

Stefan Burger ◽

Karina Hemmer ◽

Gregor Kieslich

Keyword(s):

High Pressure ◽

State Of The Art ◽

Energy Landscape ◽

Structural Flexibility ◽

Zeolitic Imidazolate Frameworks ◽

Stimuli Responsive ◽

X Ray Diffraction ◽

X Ray ◽

Open Questions ◽

Metal Organic

The zeolitic imidazolate frameworks ZIF-8 and ZIF-67 harbour a series of fascinating stimuli responsive properties. Looking at their responsitivity to hydrostatic pressure as stimulus, open questions exist regarding the isotropic compression with non-penetrating pressure transmitting media. By applying a state-of-the-art high-pressure powder X-ray diffraction setup, we revisit the high-pressure behaviour of ZIF-8 and ZIF-67 up to <i>p</i> = 0.4 GPa in small pressure increments. We observe a drastic, reversible change of high-pressure powder X-ray diffraction data at <i>p</i> = 0.3 GPa, discovering large volume structural flexibility in ZIF-8 and ZIF-67. Our results imply a shallow underlying energy landscape in ZIF-8 and ZIF-67, an observation that might point at rich polymorphism of ZIF-8 and ZIF-67, similar to ZIF-4(Zn).<br>

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Metal-Organic Framework Transistors for Dopamine Sensing

Materials Chemistry Frontiers ◽

10.1039/d1qm00118c ◽

2021 ◽

Author(s):

Jiajun Song ◽

Jianzhong Zheng ◽

Anneng Yang ◽

Hong Liu ◽

Zeyu Zhao ◽

...

Keyword(s):

Charge Transport ◽

Transport Properties ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

High Porosity ◽

Two Dimensional ◽

Metal Organic ◽

Organic Framework

Two-dimensional (2D) conductive metal-organic frameworks (MOFs) can not only inherit the high porosity and tailorability of traditional MOFs but also exhibit unique charge transport properties, offering promising opportunities for applications...

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