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Iron(III) aminoterephthalate Metal-Organic Frameworks (Fe-BDC-NH2 MOFs) have been demonstrated to show potential for relevant industrial and societal applications (i.e., catalysis, drug delivery, gas sorption). Nevertheless, further analysis is required in order to achieve their commercial production. In this work, a systematic synthetic strategy has been followed, carrying out microwave (MW) assisted hydro/solvothermal reactions to rapidly evaluate the influence of different reaction parameters (e.g., time, temperature, concentration, reaction media) on the formation of the benchmarked MIL-101-NH2, MIL-88B-NH2, MIL-53-NH2 and MIL-68-NH2 solids. Characterization of the obtained solids by powder X-ray diffraction, dynamic light scattering and transmission electron microscopy allowed us to identify trends to the contribution of the evaluated parameters, such as the relevance of the concentration of precursors and the impact of the reaction medium on phase crystallization. Furthermore, we presented here for the first time the MW assisted synthesis of MIL-53-NH2 in water. In addition, pure MIL-101-NH2 was also produced in water while MIL-88-NH2 was the predominant phase obtained in ethanol. Pure phases were produced with high space-time yields, unveiling the potential of MW synthesis for MOF industrialization. [ABSTRACT FROM AUTHOR]

The efficiency of a catalytic process is assessed based on conversion, yield, and time effectiveness. However, these parameters are insufficient for evaluating environmentally sustainable research. As the world is urged to shift towards green catalysis, additional factors such as reaction media, raw material availability, sustainability, waste minimization and catalyst biosafety, need to be considered to accurately determine the efficacy and sustainability of the process. By combining the high porosity and versatility of metal organic frameworks (MOFs) and the activity of gold nanoparticles (AuNPs), efficient, cyclable and biosafe composite catalysts can be achieved. Thus, a composite based on AuNPs and the nanometric flexible porous iron(III) aminoterephthalate MIL‐88B‐NH2 was successfully synthesized and fully characterized. This nanocomposite was tested as catalyst in the reduction of nitroarenes, which were identified as anthropogenic water pollutants, reaching cyclable high conversion rates at short times for different nitroarenes. Both synthesis and catalytic reactions were performed using green conditions, and even further tested in a time‐optimizing one‐pot synthesis and catalysis experiment. The sustainability and environmental impact of the catalytic conditions were assessed by green metrics. Thus, this study provides an easily implementable synthesis, and efficient catalysis, while minimizing the environmental and health impact of the process. [ABSTRACT FROM AUTHOR]

The recent description of well-defined molecular subtypes of breast cancer has led to the clinical development of a number of successful molecular targets. Particularly, triple-negative breast cancer (TNBC) is an aggressive type of breast cancer with historically poor outcomes, mainly due to the lack of effective targeted therapies. Recent progresses in materials science have demonstrated the impressive properties of metal–organic framework nanoparticles (NPs) as antitumoral drug delivery systems. Here, in a way to achieve efficient bio-interfaces with cancer cells and improve their internalization, benchmarked MIL-100(Fe) NPs were coated with cell membranes (CMs) derived from the human TNBC cell line MDA-MB-468. The prepared CMs-coated metal–organic framework (CMs_MIL-100(Fe)) showed enhanced colloidal stability, cellular uptake, and cytotoxicity in MDA-MB-468 cells compared to non-coated NPs, paving the way for these human CMs-coated MIL-100(Fe) NPs as effective targeted therapies against the challenging TNBC. [ABSTRACT FROM AUTHOR]

Two new lanthanide-complexes based on the 5-nitropicolinate ligand (5-npic) were obtained and fully characterized. Single-crystal X-ray diffraction revealed that these compounds are isostructural to a Dy-complex, previously published by us, based on dinuclear monomers link together with an extended hydrogen bond network, providing a final chemical formula of [Ln2(5-npic)6(H2O)4]·(H2O)2, where Ln = Dy (1), Gd (2), and Tb (3). Preliminary photoluminescent studies exhibited a ligand-centered emission for all complexes. The potential antitumoral activity of these materials was assayed in a prostatic cancer cell line (PC-3; the 2nd most common male cancerous disease), showing a significant anticancer activity (50–60% at 500 μg·mL−1). In turn, a high biocompatibility by both, the complexes and their precursors in human immunological HL-60 cells, was evidenced. In view of the strongest toxic effect in the tumoral cell line provided by the free 5-npic ligand (~ 40–50%), the overall anticancer complex performance seems to be triggered by the presence of this molecule. [ABSTRACT FROM AUTHOR]

Pharmaceutical and personal care products (PPCPs) are regarded as an emerging class of contaminants, which are often released directly into the environment, causing severe deleterious effects. In particular, the widely prescribed β-blocker atenolol (At) is alarmingly present in water. Despite the toxicity caused by At, no specific methods are currently available for its efficient removal. Here, 8 highly porous metal–organic frameworks (MOFs) with a priori remarkable aqueous stability and exceptional porosity were proposed for the removal of At. A robust nickel bispyrazolate MOF (Ni8BDP6) was selected as the most promising adsorbent, further improving its At decontamination efficiency (92–100%) and stability (<1% degradation) by using its defective version, KOH@Ni8BDP6. Finally, the At removal was studied for the first time using a MOF-continuous flow column-device under realistic conditions (tap drinking water and river water, and considering the MOF integrity), achieving a very high contaminant removal efficiency for consecutive 12 days (ca. 90%) and envisioning the future real application of MOFs in water remediation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Metal-Organic Frameworks (MOFs) as platform in of advanced combined therapy. • Biocompatibility is achieved by selecting non-toxic and/or endogenous building units. • Large porosity enables the co-encapsulation of multiple drugs in MOFs. • MOFs scaffolds can be used for theranosis, combining therapy and imaging. Abstract Different strategies have been developed to overcome limitations of traditional pharmacological treatments (biodegradation, low specificity, toxicity, side effects). Remarkably, the use of nanoplatforms as Drug Delivery Systems (DDS) to control the dose and the delivery kinetics of active ingredients (AIs) stands out as promising new generation of personalized therapies. Among other proposed materials, Metal-Organic Frameworks (MOFs) offer multiple versatilities for the accommodation of AIs: adaptable structure based on organic ligands and inorganic clusters as building units (BUs), that can be AIs themselves; accessible porosity and large surface areas; availability of functionalization sites; and biodegradability, among others. It is of great importance that MOFs, selected as bioplatforms, are biocompatible and do not exhibit toxicity. Even there are plenty of studies and reviews that explored the use of MOFs as DDS, they often include a single AI. In contrast, we wanted to focus on this review on MOF bioplatforms that exhibit advanced combined therapies. These advanced therapies could be achieved by: i) the co-encapsulation and simultaneous or sequential release of two or more AIs (e.g. drugs, metals, gases, biomolecules), ii) effective drug delivery at a target site after external triggered stimulus (near infrared-NIR, magnetic field), iii) monitoring administration towards a specific target (bioimaging), iv) combined AIs delivery and diagnosis (theranosis), and v) detection of different analytes (biosensors). All the promising combined advanced therapies based on MOFs bioplatforms herein reported open the path for the development of more efficient treatments. [ABSTRACT FROM AUTHOR]

Hierarchical porous UiO-66-NH2 cm-monolithic xero- and aero-gels with a controlled shape and mechanical robustness were successfully produced from ethanolic gels. Their remarkable controlled hierarchical porosity was effectively assessed using N2 sorption, Hg intrusion porosimetry and focused ion beam-scanning electron microscopy methods. [ABSTRACT FROM AUTHOR]

A new heterogeneous bio-catalyst was synthesized by encapsulating lipase into the microporous zeolite imidazolate framework, ZIF-67, using a bottle-around-a-ship method. The enzyme/ZIF-67 association is higher than those resulting from post-synthetic approaches. The resulting biocomposite lipase@ZIF-67 was fully characterized by UV-vis and Fourier transform infrared (FT-IR) spectroscopies, powder X-ray diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), Thermal gravimetric analyses (TGA), N 2 adsorption–desorption and energy dispersive X-ray (EDX). The prepared bio-catalyst was successfully applied for transesterification of soybean oil to biodiesel in a solvent-free medium. The effect of different parameters, such as pH, temperature, molar ratio of methanol to oil and mass ratio of bio-catalyst to oil, was deeply investigated. Finally, the immobilized enzyme was reused during 6 cycles transesterification reaction without a significant decrease in its initial activity. This simple and efficient association procedure seems well-adapted to produce enzymatic bio-catalyst for biodiesel production. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) are highly versatile materials. Here, two novel MOFs, branded as IEF-23 and IEF-24 and based on an antibacterial tricarboxylate linker and zinc or copper cations, and holding antibacterial properties, are presented. The materials were synthesized by the solvothermal route and fully characterized. The antibacterial activity of IEF-23 and IEF-24 was investigated against Staphylococcus epidermidis and Escherichia coli via the agar diffusion method. These bacteria are some of the most broadly propagated pathogens and are more prone to the development of antibacterial resistance. As such, they represent an archetype to evaluate the efficiency of novel antibacterial treatments. MOFs were active against both strains, exhibiting higher activity against Staphylococcus epidermidis. Thus, the potential of the developed MOFs as antibacterial agents was proved. [ABSTRACT FROM AUTHOR]

Surface microbial colonization and its potential biofilm formation are currently a major unsolved problem, causing almost 75% of human infectious diseases. Pathogenic biofilms are capable of surviving high antibiotic doses, resulting in inefficient treatments and, subsequently, raised infection prevalence rates. Antibacterial coatings have become a promising strategy against the biofilm formation in biomedical devices due to their biocidal activity without compromising the bulk material. Here, we propose for the first time a silver-based metal–organic framework (MOF; here denoted AgBDC) showing original antifouling properties able to suppress not only the initial bacterial adhesion, but also the potential surface contamination. Firstly, the AgBDC stability (colloidal, structural and chemical) was confirmed under bacteria culture conditions by using agar diffusion and colony counting assays, evidencing its biocide effect against the challenging E. coli, one of the main representative indicators of Gram-negative resistance bacteria. Then, this material was shaped as homogeneous spin-coated AgBDC thin film, investigating its antifouling and biocide features using a combination of complementary procedures such as colony counting, optical density or confocal scanning microscopy, which allowed to visualize for the first time the biofilm impact generated by MOFs via a specific fluorochrome, calcofluor. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) can be used as reservoirs of metal ions with relevant antibacterial effects. Here, two novel Zn-based MOFs with the formulas [Zn4(μ4-O)(μ-FA)L2] (GR-MOF-8) and [Zn4(μ4-O)L2(H2O)] (GR-MOF-9) (H3L: 5-((4-carboxyphenyl)ethynyl) in isophthalic acid and FA (formate anion) were solvothermally synthetized and fully characterized. The antibacterial activity of GR-MOF-8 and 9 was investigated against Staphylococcus aureus (SA) and Escherichia Coli (EC) by the agar diffusion method. Both bacteria are among the most relevant human and animal pathogens, causing a wide variety of infections, and are often related with the development of antimicrobial resistances. While both Zn-based materials exhibited antibacterial activity against both strains, GR-MOF-8 showed the highest inhibitory action, likely due to a more progressive Zn release under the tested experimental conditions. This is particularly evidenced in the inhibition of SA, with an increasing effect of GR-MOF-8 with time, which is of great significance to ensure the disappearance of the microorganism. [ABSTRACT FROM AUTHOR]

Photocatalysis process is a promising technology for environmental remediation. In the continuous search of new heterogeneous photocatalysts, metal–organic frameworks (MOFs) have recently emerged as a new type of photoactive materials for water remediation. Particularly, titanium-based MOFs (Ti-MOFs) are considered one of the most appealing subclass of MOFs due to their promising optoelectronic and photocatalytic properties, high chemical stability, and unique structural features. However, considering the limited information of the reported studies, it is a hard task to determine if real-world water treatment is attainable using Ti-MOF photocatalysts. In this paper, via a screening with several Ti-MOFs, we originally selected and described the potential of a Ti-MOF in the photodegradation of a mixture of relevant Emerging Organic Contaminants (EOCs) in real water. Initially, two challenging drugs (i.e., the β-blocker atenolol (At) and the veterinary antibiotic sulfamethazine (SMT)) and four water stable and photoactive Ti-MOF structures have been rationally selected. From this initial screening, the mesoporous Ti-trimesate MIL-100(Ti) was chosen as the most promising photocatalyst, with higher At or SMT individual photodegradation (100% of At and SMT photodegradation in 2 and 4 h, respectively). Importantly, the safety of the formed by-products from the At and SMT photodegradation was confirmed. Finally, the At and SMT photodegradation capacity of MIL-100(Ti) was confirmed under realistic conditions, by using a mixture of contaminants in tap drinking water (100% of At and SMT photodegradation in 4 h), proven in addition its potential recyclability, which reinforces the potential of MIL-100(Ti) in water remediation. [ABSTRACT FROM AUTHOR]

Highlights: [•] We study the sorption of hexane isomers in ZIF-8 by fixed bed adsorption. [•] The sorption of linear nHEX is remarkable with a working capacity around 25wt%. [•] A complete separation between linear nHEX and the branched isomers is observed. [ABSTRACT FROM AUTHOR]

In the last two decades, the field of metal–organic frameworks (MOFs) has exploded, and MOF nanoparticles in particular are being investigated with increasing interest for various applications, including gas storage and separation, water harvesting, catalysis, energy conversion and storage, sensing, diagnosis, therapy, and theranostics. To further pave their way into real-world applications, and to push the synthesis of MOF nanoparticles that are 'safe-and-sustainable-by-design', this tutorial review aims to shed light on the importance of a systematic toxicity assessment. After clarifying and working out the most important terms and aspects from the field of nanotoxicity, the current state-of-the-art of in vitro and in vivo toxicity studies of MOF nanoparticles is evaluated. Moreover, the key aspects affecting the toxicity of MOF nanoparticles such as their chemical composition, their physico-chemical properties, including their colloidal and chemical stability, are discussed. We highlight the need of more targeted synthesis of MOF nanoparticles that are 'safe-and-sustainable-by-design', and their tailored hazard assessment in the context of their potential applications in order to tap the full potential of this versatile material class in the future. [ABSTRACT FROM AUTHOR]

• Rats were exposed to 50, 100 and 200 mg/kg bw TiO 2 NPs via intragastric administration for 8 weeks. • TiO 2 NPs can reach the brain and cross the brain blood barrier (BBB) to been accumulated in the barin of rats. • TiO 2 NPs caused cerebral oxidative stress damage, increased NO levels and histopathological injury. • TiO 2 NPs led to a neurotoxic damage. • TiO 2 NPs increased degenerated and apoptotic neurons in cerebral cortex. Titanium dioxide nanoparticles were widely used in food as dietary supplements, in drugs, in toothpaste, ect. Few numbers of studies were interested to the neurotoxicity of TiO 2 NPs through oral pathway. The present study aims firstly to understand the connection between the physicochemical properties of TiO 2 NPs and their associated toxicological oral pathway by evaluation the colloidal stability of TiO 2 NPs over time in different media simulating physiological gastric, intestinal and serum conditions at 37 °C to be close to the oral administraton. Secondly, this study aims to evaluate the neurotoxicity of a subchronic intragastric administration of TiO 2 NPs to rats. Different doses of anatase TiO 2 NPs were administrated to Wistar rats every day for consecutives eight weeks. Titanium (Ti) content in brain, oxidative antioxidant biomarkers, lipid peroxidation, nitric oxide (NO) levels, tumor necrosis factor-alpha (TNF-α) levels, histophatological changes, degenerated and apoptosis neurons were investigated. Results suggested that TiO 2 NPs can reach the brain and cross the brain blood barrier (BBB) to been accumulated in the brain of rats causing cerebral oxidative stress damage, increasing NO levels and histopathological injury. At higher dose, we observed the most cerebral injury by the highest accumulation of Ti and by the remarkable increase of TNF-α besides to the most increase of degenerated and apoptosis neurons in the brain of exposed rats. TiO 2 NPs led to a neurotoxic damage accompanied by the increase of degenerated and apoptotic neurons in cerebral cortex. [ABSTRACT FROM AUTHOR]

A new robust Bi-carboxylate metal–organic framework (MOF) IEF-2 was hydrothermally prepared, acting as a proton carrier (σ∼ 1.1 × 10−4 S cm−1). Such proton conductivity is among the highest reported so far for purely 3D carboxylate-based MOFs, being explained by the existence of a 1D hydrogen-bond network, as suggested by structural analysis and theoretical studies. [ABSTRACT FROM AUTHOR]

Despite the higher efficiency, larger color range and faster stimulus response of polymeric electrochromic materials, their poor cyclability strongly hampers their application in optoelectronics. As an original strategy to stabilize and further nanostructure these polymers, herein an efficient encapsulation and in situ polymerization inside highly porous metal–organic frameworks (MOFs) is reported. In particular, the successful accommodation of poly(3,4-ethylendioxythiophene) (PEDOT) and its partially oxidized polarons inside the mesopores of the nontoxic iron trimesate MIL-100(Fe) is convincingly proved by a large panel of experimental techniques. Remarkably, the polymer–MOF interaction occurring for entrapped PEDOT within the pores (deeply assessed by experimental and simulation methods) might be responsible for the enhanced electrical conductivity of the resulting PEDOT@MIL-100(Fe) composite when compared to the insulating MIL-100(Fe) and the conductive free PEDOT. Furthermore, it was possible to observe the electrochromic properties of the PEDOT@MIL-100(Fe) composite, achieving an improved stability and good cyclability as a consequence of the effective protection by the MOF matrix. [ABSTRACT FROM AUTHOR]

The commercialization of oxygen-related energy storage/conversion devices, for instance metal-air batteries or fuel cells, is highly dependent on development of low-cost, high performance electrocatalysts for oxygen reduction/oxygen evolution reactions (ORR and OER). In the present study, we employed Co-ZIF-9 as a sacrificial precursor to synthesize highly efficient bifunctional ORR/OER electrocatalysts through tuning the pyrolysis temperature and Fe-doping of the zeolitic imidazolate framework. The synthesized samples were characterized extensively using X-ray photoelectron spectroscopy (XPS), X-ray diffraction, elemental CHN and ICP analyses, and Fourier transform infrared (FTIR) spectroscopy as well as scanning (SEM) and transmission (TEM) electron microscopies. It has been found that the Fe-doping can significantly affect the electrocatalytic activity of the product through improving the number of transferred electrons. The ZIF-9_Fe3_Pyrol exhibited excellent electrocatalytic activity towards ORR (E onset = 0.90 V vs. RHE) and OER (E onset = 1.55 V vs. RHE), much better than other evaluated catalysts and comparable to the commercial PtRuC bifunctional catalyst. Moreover, the ZIF-9_Fe3_Pyrol sample outperformed the precious PtRuC catalyst with very little decay in ORR and OER activity over long continuous operation. The ZIF-9_Fe3_Pyrol exhibited excellent performance as a cathode catalyst in rechargeable Zn-air batteries, superior to the one assembled with the state-of-the-art catalyst. Image 1 • Fe/Co-bimetal ZIF-9 as sacrificial precursor towards highly efficient ORR/OER electrocatalyst. • Fe-doping affects electrocatalytic activity and improves the number of transferred electrons. • ZIF-9_Fe3_Pyrol shows excellent performance in Zn-air batteries (815 mAh∙g−1, 1018 Wh∙kg Zn −1). [ABSTRACT FROM AUTHOR]

A plasmonic core–shell gold nanostar/zeolitic‐imidazolate‐framework‐8 (ZIF‐8) nanocomposite was developed for the thermoplasmonic‐driven release of encapsulated active molecules inside living cells. The nanocomposites were loaded, as a proof of concept, with bisbenzimide molecules as functional cargo and wrapped with an amphiphilic polymer that prevents ZIF‐8 degradation and bisbenzimide leaking in aqueous media or inside living cells. The demonstrated molecule‐release mechanism relies on the use of near‐IR light coupled to the plasmonic absorption of the core gold nanostars, which creates local temperature gradients and thus, bisbenzimide thermodiffusion. Confocal microscopy and surface‐enhanced Raman spectroscopy (SERS) were used to demonstrate bisbenzimide loading/leaking and near‐IR‐triggered cargo release inside cells, thereby leading to DNA staining. [ABSTRACT FROM AUTHOR]

The novel 2D bismuth–camphorate IEF‐1, formulated as [Bi(L)(HL)] (where H2L = camphoric acid), has been successfully isolated as large single crystals and easily scaled up by hydrothermal synthesis. The crystalline structure of IEF‐1 was unveiled by single‐crystal X‐ray diffraction, in the monoclinic space group P21, and fully characterized by using several standard solid‐state techniques. IEF‐1 material is thermally stable up to ca. 240 °C without any visible structural change. In addition, the study of the nonlinear optical (NLO) properties of IEF‐1 by second harmonic generation (SHG) microscopy evidenced that IEF‐1 is noncentrosymmetric and has a more intensive blue component that may be explained by the ligand to metal charge transfer behavior. [ABSTRACT FROM AUTHOR]

Correction for 'Toxicity of metal–organic framework nanoparticles: from essential analyses to potential applications' by Romy Ettlinger et al., Chem. Soc. Rev., 2022, 51, 464–484, https://doi.org/10.1039/D1CS00918D. [ABSTRACT FROM AUTHOR]

The article focuses on the confinement of bisphosphonate drug in the pores of silica-based ordered mesoporous materials for a local and controlled drug delivery. The materials are found to induce apatite formation in physiological fluids. This characteristic of silica-based ordered mesoporous materials together with the possibility of confining bisphosphonates suggests new expectancies in bone tissue regeneration.

A series of five isostructural zirconium terephthalate UiO-66 metal organic frameworks bearing different functional groups on the terephthalate linker (UiO-66-X; X = H, NH 2 , NO 2 , Br, Cl,) have been successfully prepared and characterized. UiO-66-X materials were evaluated as heterogeneous catalysts for the epoxide ring opening of styrene oxide by methanol, observing an increase in the initial reaction rate from UiO-66-H to UiO-66-Br, over one order of magnitude. The reactivity order, however, does not follow a linear relationship between the Hammett constant value of the substituent and the initial reaction rate. UiO-66-Br exhibits a wide scope, its activity depending on the structure of epoxide and nucleophile. The absence of Zr leaching to the solution together with the preservation of the UiO-66-X crystallinity confirms the stability of the framework under the reaction conditions. Nevertheless, UiO-66 undergoes a progressive deactivation upon reuse that was attributed to a strong adsorption of the reaction product. [ABSTRACT FROM AUTHOR]

Highlights: [•] IR and modeling approaches for specifying the dual interaction of propyne in MIL-53. [•] Halogen atoms act as basic sites toward propyne in functionalized MOFs. [•] Free hydroxyls interact with propyne as hydrogen donors but also as basic sites. [Copyright &y& Elsevier]

Abstract: A series of functionalized porous Zr terephthalate MOFs of the UiO-66(Zr) structure type bearing either Br, NH2 or NO2 groups have been synthesized at the multi-gram scale through an atmospheric pressure solvothermal route with the final aim of investigating the influence of functionalization on the separation of hexane isomers (22DMB, 23DMB, 3MP and nHEX). The studies performed in a fixed bed adsorption column with equimolar mixtures at temperatures between 343 and 423K and partial pressure up to 10kPa have shown that the Br, NO2 and NH3 forms exhibit an uptake reaching 15%, being the sorption selectivity hierarchy on the whole comparable to the bared UiO-66 solid: 22DMB≈23DMB>3MP≫ nHEX. The 22DMB/nHEX selectivity reaches approximately three at low uptake while the 22DMB/3MP selectivity of UiO-66_NO2 is nearly constant (1.3). [Copyright &y& Elsevier]

Abstract: The adsorption of n-hexane and n-nonane in MIL-53(Cr) and MIL-47(V) was first investigated by gravimetric measurements. While MIL-53(Cr) exhibits a sub-step during the sorption process induced by the breathing ability of this solid, the adsorption isotherm for MIL-47(V) is of type I. This different shape of the so-obtained isotherms was then interpretated in light of complementary experimental tools including thermogravimetry and X-ray thermodiffraction. We thus evidenced the occurrence of different structures in presence of n-hexane or n-nonane in the case of MIL-53(Cr) identified as the narrow pore (NP) phase and large pore (LP) phase. One noticed the existence of a swollen NP form which spans in a broad range of temperature. A computational assisted structure determination allowed us to elucidate the structures for both NP and LP forms in presence of each investigated alkane. From these structures, the adsorption enthalpies of n-alkanes over MIL-53(Cr) have been computed. It was shown that the NP phase leads to higher enthalpy of adsorption as compared to the LP phase which is related to a higher degree of confinement. [ABSTRACT FROM AUTHOR]

A comparison of the adsorption of water, methanol, and ethanol polar vapors by the flexible porous chromium(lll) terephthalate MIL-53(Cr) was investigated by complementary techniques including adsorption gravimetry, ex situ X-ray powder diffraction, microcalorimetry, thermal analysis, I R spectroscopy, and molecular modeling. The breathing steps observed during adsorption strongly depend on the nature of the vapor. With water, a significant contraction of the framework is observed. For the alcohols, the initial contraction is followed by an expansion of the framework. A combination of IR analysis, X-ray diffraction, and computer modeling leads to the molecular localization of the guest molecules and to the identification of the specific guest-guest and host-guest interactions. The enthalpies of adsorption, measured by microcalonmetry, show that the strength of the interactions decreases from ethanol to water. Differential scanning calorimetry experiments on an EtOH/ H2O mixture suggest a selective adsorption of ethanol over water. [ABSTRACT FROM AUTHOR]

Abstract: The adsorption of Cl to C4 linear hydrocarbons in the flexible metal organic framework MIL- 53(Cr) has been followed by adsorption manometry coupled with microcalorimetry and Synchrotron X-ray powder diffraction. This experimental investigation was completed by molecular modeling. In the case of methane, the solid remains rigid whatever the adsorbate amount. However for the C2-C4 series, an increasing flexibility of the structure is observed, which is ascribed first to a breathing of the material from a large pore to a narrow pore form followed by a further expansion at high pressure. The collected thermodynamic and structural information suggests that a minimum adsorption enthalpy of ca. 20 kJ mol—1 in the initial large pore structure of MIL-53(Cr) is required to induce the structural transition "large to narrow pore". Further, the enthalpy of adsorption can be used to predict the pressure at which the structure reopens. Finally, the magnitude of the breathing can be related to the size of the probe molecule via the van der Waals volume. The above trends have been successfully verified in the case of water and carbon dioxide. This combined experimental and theoretical approach gives the first elements for the prediction of whether or not the MIL-53 and similar flexible structures will respond to gas loading and what would be the pressure required and further the amplitude of the induced breathing. [ABSTRACT FROM AUTHOR]

Supercritical CO 2 (scCO 2) technology is used here as an efficient method to assist in the preparation of a cutaneous polymeric formulation based on drug containing metal-organic framework composites. The supercritical fluid is used in three steps: (i) as a drying agent for the nanosized mesoporous matrix, (ii) as the impregnation vector of a topical antibiotic drug, and (iii) as a plasticizing and foaming fluid to obtain dispersions of the hybrid material into a biocompatible polymer, e.g. , the macroporous patch. The materials were characterized using solid state techniques. The drug delivery and permeation profiles of the patches were investigated applying in vitro and ex vivo tests by using porcine skin. These analyses suggest that scCO 2 impregnation is an easy and fast strategy to prepare composite devices able to progressively release and diffuse the incorporated drug throughout the skin, paving the way to efficiently prepare cutaneous devices for topical or systemic therapies. [Display omitted] • MOF synthesis, drug encapsulation and device preparation using green scCO 2 method. • Use of additives, organic solvents and cleaning steps are minimized. • Drug diffusion from scCO 2 is more efficient than by impregnation from water. • Topical delivery and skin permeation of the drug occurs in a controlled rate. [ABSTRACT FROM AUTHOR]

The new [Ni(dmbpy)(H 2 O) 4 SeO 4 complex (dmbpy = 5,5′-dimethyl-2,2′-bipyridine or C 12 H 12 N 2), based on mononuclear nickel(II) and bi-atomic bridging ligands has been successfully synthesized by hydrothermal method. The crystals are characterized by X-ray single-crystal diffraction, crystallizing in the monoclinic system, space group P2 1 /c. Their crystal structure consists of metallic cations octahedrally coordinated by four water molecules and two nitrogen atoms coming from the organic molecule [NiN 2 O 4 , and a selenate anion (SeO 4)2-. Their crystal packing is ensured by a three-dimensional network of O-H...O hydrogen bonds between the cation and anion moieties, and π ... π interactions between the pyridine rings of the organic moieties of the same layer. The thermal analysis discloses dehydration between 148 °C and 210 °C, leading to an anhydrous compound [Ni(dmbpy]SeO 4. The study of vibrational absorption and Raman scattering spectra allows bringing additional information to those obtained by X-ray diffraction. The optical band gap was calculated from the UV–Vis absorbance spectra using classical Tauc relation which was found to be 3.58 eV. The catalytic evaluation of [Ni(dmbpy)(H 2 O) 4 SeO 4 on Heck and Sonogashira coupling reactions, activated by ultrasonic irradiation, results in encouraging yields for a very short times with a remarkable selectivity of the form (E) with respect to (Z) during the arylation of styrene, making this complex a promising catalyst for both types of reactions. The coupling products of the Heck and Sonogashira coupling reaction ((Z)-/(E)- Stilbene and Diphenylacetylene, respectively) were examined by 13C NMR and 1H NMR. These spectroscopic measurements provide extremely valuable information on the structure of the molecules obtained. Crystal structure and catalyst activity of a cobalt complex, [Ni(dmbpy))(H 2 O) 4 SeO 4. Image 1 • [Ni(C 12 H 12 N 2)(H 2 O) 4 SeO 4 was synthesized via hydrothermal reaction. • This compound crystallizes in the monoclinic P2 1 /c space group. • Catalytic activities of [Ni(dmbpy))(H 2 O) 4 SeO 4 for Heck and Sonogashira coupling explored. Synopsis: Mononuclear Ni(II) complex with 5,5'dimethyl-2,2-bipyridine has been synthesized and structurally characterized using single-crystal X-ray diffraction studies. Reactivity studies indicate that the mononuclear complex is an unusually active catalyst for the Heck and sonogaschira reaction. [ABSTRACT FROM AUTHOR]

Plastic pollution is one of the main worldwide environmental concerns. Our lifestyle involves persistent plastic consumption, aggravating the low efficiency of wastewater treatment plants in its removal. Nano/microplastics are accumulated in living beings, pushing to identify new water remediation strategies to avoid their harmful effects. Enzymes (e. g., Candida rugosa-CrL) are known natural plastic degraders as catalysts in depolymerization reactions. However, their practical use is limited by their stability, recyclability, and economical concerns. Here, enzyme immobilization in metal-organic frameworks (CrL&#95;MOFs) is originally presented as a new plastic degradation approach to achieve a boosted plastic decomposition in aqueous systems while allowing the catalyst cyclability. Bis-(hydroxyethyl)terephthalate (BHET) was selected as model substrate for decontamination experiments for being the main polyethylene terephthalate (PET) degradation product. Once in contaminated water, CrL&#95;MOFs can eliminate BHET (37 %, 24 h), following two complementary mechanisms: enzymatic degradation (CrL action) and byproducts adsorption (MOF effect). As a proof-of-concept, the capacity of a selected CrL&#95;MOF composite to eliminate the BHET degradation products and its reusability are also investigated. The potential of these systems is envisioned in terms of improving enzyme cyclability, reducing costs along with feasible co-adsorption of plastic byproducts and other harmful contaminants, to successfully remove them in a single step., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

Physicochemical properties of polymers strongly depend on the arrangement and distribution of attached monomers. Templated polymerization using porous crystalline materials appears as a promising route to gain control on the process. Thus, we demonstrate here the potential of metal-organic frameworks as scaffolds with a versatile and very regular porosity, well adapted for the regioselective oxidative polymerization of pyrene. This photoresponsive monomer was first encapsulated within the one-dimensional (1D) microporosity of the robust zirconium(IV) carboxylate metal-organic framework (MOF) (MIL-140D) to, later, undergo in situ oxidative polymerization, enabling the growth of a highly selective polypyrene (PPyr) regioisomer over other potential polymer configurations. To confirm the polymerization and the geometry control of pyrene, the resulting composites were exhaustively characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), N 2 sorption measurements, scanning transmission electron microscopy coupled with energy-dispersive X-ray (STEM-EDX) spectroscopy, and fluorescence spectroscopy. Among others, photoluminescence quenching and emission shift in the solid state demonstrated the presence of PPyr inside the MOF porosity. Furthermore, an in-depth joint analysis combining solid-state, magic-angle spinning (MAS) 1 H and 13 C NMR spectroscopy, Fourier transform infrared (FTIR) spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS), and molecular simulations (grand canonical Monte Carlo (GCMC) and density functional theory (DFT)) allowed the elucidation of the spatial, host-guest interactions driving the polymerization reaction.

Nitrogen oxides represent one of the main threats for the environment. Despite decades of intensive research efforts, a sustainable solution for NO x removal under environmental conditions is still undefined. Using theoretical modelling, material design, state-of-the-art investigation methods and mimicking enzymes, it is found that selected porous hybrid iron(II/III) based MOF material are able to decompose NO x , at room temperature, in the presence of water and oxygen, into N 2 and O 2 and without reducing agents. This paves the way to the development of new highly sustainable heterogeneous catalysts to improve air quality., (© 2024 Wiley‐VCH GmbH.)

Through this inspirational note, we would like to highlight the potential of nanoscaled metal-organic frameworks within the biomedical field. The unique properties of these materials that make them promising candidates for new nanomedicines are assessed here as well as the progression reached so far for combinational cancer therapies and theranostic, along with its most recent advances in nanomedicine. Finally, the perspective and challenges of these materials within this field is discussed., (© 2024. Controlled Release Society.)

When bulk materials are reduced in size to the nanometer scale, in particular, their surface-to-volume ratio increases drastically. We introduce some simple experiments on how to visualize this concept to students in the framework of a laboratory class. In the same context, experiments to demonstrate the consequences of this on the properties of the materials are introduced. This will involve solubility and chemical surface reactivity of the materials and properties originated from the surface. In the framework of their chemical reactivity, potential benefits and threads of nanomaterials due to their high surface-to-volume ratio will be discussed, such as applications as catalysts and their impact on nanotoxicology., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society and Division of Chemical Education, Inc.)

The SARS-CoV-2 (COVID-19) pandemic outbreak led to enormous social and economic repercussions worldwide, felt even to this date, making the design of new therapies to combat fast-spreading viruses an imperative task. In the face of this, diverse cutting-edge nanotechnologies have risen as promising tools to treat infectious diseases such as COVID-19, as well as challenging illnesses such as cancer and diabetes. Aside from these applications, nanoscale metal-organic frameworks (nanoMOFs) have attracted much attention as novel efficient drug delivery systems for diverse pathologies. However, their potential as anti-COVID-19 therapeutic agents has not been investigated. Herein, we propose a pioneering anti-COVID MOF approach by studying their potential as safe and intrinsically antiviral agents through screening various nanoMOF. The iron(III)-trimesate MIL-100 showed a noteworthy antiviral effect against SARS-CoV-2 at the micromolar range, ensuring a high biocompatibility profile (90% of viability) in a real infected human cellular scenario. This research effectively paves the way toward novel antiviral therapies based on nanoMOFs, not only against SARS-CoV-2 but also against other challenging infectious and/or pulmonary diseases.

The efficiency of a catalytic process is assessed based on conversion, yield, and time effectiveness. However, these parameters are insufficient for evaluating environmentally sustainable research. As the world is urged to shift towards green catalysis, additional factors such as reaction media, raw material availability, sustainability, waste minimization and catalyst biosafety, need to be considered to accurately determine the efficacy and sustainability of the process. By combining the high porosity and versatility of metal organic frameworks (MOFs) and the activity of gold nanoparticles (AuNPs), efficient, cyclable and biosafe composite catalysts can be achieved. Thus, a composite based on AuNPs and the nanometric flexible porous iron(III) aminoterephthalate MIL-88B-NH 2 was successfully synthesized and fully characterized. This nanocomposite was tested as catalyst in the reduction of nitroarenes, which were identified as anthropogenic water pollutants, reaching cyclable high conversion rates at short times for different nitroarenes. Both synthesis and catalytic reactions were performed using green conditions, and even further tested in a time-optimizing one-pot synthesis and catalysis experiment. The sustainability and environmental impact of the catalytic conditions were assessed by green metrics. Thus, this study provides an easily implementable synthesis, and efficient catalysis, while minimizing the environmental and health impact of the process., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Metal-organic frameworks (MOFs) possess a variety of interesting features related to their composition and structure that make them excellent candidates to be used in agriculture. However, few studies have reported their use as delivery agents of agrochemicals. In this work, the natural polyphenol chlorogenic acid (CGA) was entrapped via simple impregnation in the titanium aminoterephthalate MOF, MIL-125-NH 2 . A combination of experimental and computational techniques was used to understand and quantify the encapsulated CGA in MIL-125-NH 2 . Subsequently, CGA delivery studies were carried out in water at different pHs, showing a fast release of CGA during the first 2 h (17.3 ± 0.3% at pH = 6.5). In vivo studies were also performed against larvae of mealworm ( Tenebrio molitor ), evidencing the long-lasting insecticidal activity of CGA@MIL-125-NH 2 . This report demonstrates the potential of MOFs in the efficient release of agrochemicals, and paves the way to their study against in vivo models.

The need to develop green and cost-effective industrial catalytic processes has led to growing interest in preparing more robust, efficient, and selective heterogeneous catalysts at a large scale. In this regard, microwave-assisted synthesis is a fast method for fabricating heterogeneous catalysts (including metal oxides, zeolites, metal-organic frameworks, and supported metal nanoparticles) with enhanced catalytic properties, enabling synthesis scale-up. Herein, the synthesis of nanosized UiO-66-NH 2 was optimized via a microwave-assisted hydrothermal method to obtain defective matrices essential for the stabilization of metal nanoparticles, promoting catalytically active sites for hydrogenation reactions (760 kg·m -3 ·day -1 space time yield, STY). Then, this protocol was scaled up in a multimodal microwave reactor, reaching 86% yield (ca. 1 g, 1450 kg·m -3 ·day -1 STY) in only 30 min. Afterward, Pd nanoparticles were formed in situ decorating the nanoMOF by an effective and fast microwave-assisted hydrothermal method, resulting in the formation of Pd@UiO-66-NH 2 composites. Both the localization and oxidation states of Pd nanoparticles (NPs) in the MOF were achieved using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) and X-ray photoelectron spectroscopy (XPS), respectively. The optimal composite, loaded with 1.7 wt % Pd, exhibited an extraordinary catalytic activity (>95% yield, 100% selectivity) under mild conditions (1 bar H 2 , 25 °C, 1 h reaction time), not only in the selective hydrogenation of a variety of single alkenes (1-hexene, 1-octene, 1-tridecene, cyclohexene, and tetraphenyl ethylene) but also in the conversion of a complex mixture of alkenes (i.e., 1-hexene, 1-tridecene, and anethole). The results showed a powerful interaction and synergy between the active phase (Pd NPs) and the catalytic porous scaffold (UiO-66-NH 2 ), which are essential for the selectivity and recyclability.

Pharmaceutical active compounds (PhACs) are some of the most recalcitrant water pollutants causing undesired environmental and human effects. In absence of adapted decontamination technologies, there is an urgent need to develop efficient and sustainable alternatives for water remediation. Metal-organic frameworks (MOFs) have recently emerged as promising candidates for adsorbing contaminants as well as providing photoactive sites, as they possess exceptional porosity and chemical versatility. To date, the reported studies using MOFs in water remediation have been mainly focused on the removal of a single type of PhACs and rarely on the combined elimination of PhACs mixtures. Herein, the eco-friendly bismuth-based MOF, SU-101, has been originally proposed as an efficient adsorbent-photocatalyst for the elimination of a mixture of three challenging persistent PhACs, frequently detected in wastewater and surface water in ng L -1 to mg·L -1 concentrations: the antibiotic sulfamethazine (SMT), the anti-inflammatory diclofenac (DCF), and the antihypertensive atenolol (At). Adsorption experiments of the mixture revealed that SU-101 exhibited a great adsorption capacity towards At, resulting in an almost complete removal (94.1 ± 0.8% for combined adsorption) in only 5 h. Also, SU-101 demonstrated a remarkable photocatalytic activity under visible light to simultaneously degrade DCF and SMT (99.6 ± 0.4% and 89.2 ± 1.4%, respectively). In addition, MOF-contaminant interactions, the photocatalytic mechanism and degradation pathways were investigated, also assessing the toxicity of the resulting degradation products. Even further, recycling and regeneration studies were performed, demonstrating its efficient reuse for 4 consecutive cycles without further treatment, and its subsequent successful regeneration by simply washing the material with a NaCl solution., (© 2024. The Author(s).)

The misuse and overdose of antimicrobial medicines are fostering the emergence of novel drug-resistant pathogens, providing negative repercussions not only on the global healthcare system due to the rise of long-term or chronic patients and inefficient therapies but also on the world trade, productivity, and, in short, to the global economic growth. In view of these scenarios, novel action plans to constrain this antibacterial resistance are needed. Thus, given the proven antiproliferative tumoral and microbial features of thiosemicarbazone (TSCN) ligands, we have here synthesized a novel effective antibacterial copper-thiosemicarbazone complex, demonstrating both its solubility profile and complex stability under physiological conditions, along with their safety and antibacterial activity in contact with human cellular nature and two most predominant bacterial strains, respectively. A significant growth inhibition (17% after 20 h) is evidenced over time, paving the way toward an effective antibacterial therapy based on these copper-TSCN complexes.

In the last two decades, metal-organic frameworks (MOFs) with highly tunable structure and porosity, have emerged as drug nanocarriers in the biomedical field. In particular, nanoscaled MOFs (nanoMOFs) have been widely investigated because of their potential biocompatibility, high drug loadings, and progressive release. To enhance their properties, MOFs have been combined with magnetic nanoparticles (MNPs) to form magnetic nanocomposites (MNP@MOF) with additional functionalities. Due to the magnetic properties of the MNPs, their presence in the nanosystems enables potential combinatorial magnetic targeted therapy and diagnosis. In this Review, we analyze the four main synthetic strategies currently employed for the fabrication of MNP@MOF nanocomposites, namely, mixing, in situ formation of MNPs in presynthesized MOF, in situ formation of MOFs in the presence of MNPs, and layer-by-layer methods. Additionally, we discuss the current progress in bioapplications, focusing on drug delivery systems (DDSs), magnetic resonance imaging (MRI), magnetic hyperthermia (MHT), and theragnostic systems. Overall, we provide a comprehensive overview of the recent advances in the development and bioapplications of MNP@MOF nanocomposites, highlighting their potential for future biomedical applications with a critical analysis of the challenges and limitations of these nanocomposites in terms of their synthesis, characterization, biocompatibility, and applicability., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)