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In this study, the potential of the metal-organic framework UTSA-16(Zn) as a fluorescence detector for SO 2 is explored. The material was synthesized and characterized by powder X-ray diffraction (PXRD), infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), and its fluorescence behavior was analyzed before and after SO 2 exposure. A significant decrease in fluorescence intensity was observed and a LOD of 1.79 mM (∼114.6 ppm) was obtained. With the help of time-resolved photoluminescence (TRPL) experiments and X-ray photoelectron (XPS) and ultraviolet-visible (UV-vis) spectroscopy, a static quenching mechanism due to the formation of a non-fluorescent complex in the ground state (GSC) was elucidated.

We report the inaugural experimental investigation of covalent organic frameworks (COFs) to address the formidable challenge of SO 2 detection. Specifically, an imine-functionalized COF (SonoCOF-9) demonstrated a modest and reversible SO 2 sorption of 3.5 mmol g -1 at 1 bar and 298 K. At 0.1 bar (and 298 K), the total SO 2 uptake reached 0.91 mmol g -1 with excellent reversibility for at least 50 adsorption-desorption cycles. An isosteric enthalpy of adsorption (ΔH ads ) for SO 2 equaled -42.3 kJ mol -1 , indicating a relatively strong interaction of SO 2 molecules with the COF material. Also, molecular dynamics simulations and Møller-Plesset perturbation theory calculations showed the interaction of SO 2 with π density of the rings and lone pairs of the N atoms of SonoCOF-9. The combination of experimental data and theoretical calculations corroborated the potential use of this COF for the selective detection and sensing of SO 2 at the sub-ppm level (0.0064 ppm of SO 2 )., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Hybrid organic-inorganic perovskites (HOIPs) are widely studied for their potential in optoelectronic devices due to their unique semiconductor features. Porous HOIPs are extremely rare, with (APOSS)[CuCl 4 ] 4 being one of the very few examples, featuring 12 Å pores within its lattice. Reed and coworkers (C. W. Dalton, P. M. Gannon, W. Kaminsky and D. A. Reed, Chem. Sci. , 2025, DOI: https://doi.org/10.1039/D4SC04378B) have recently shed light on the structure of this interesting material and demonstrated that these pores can incorporate large electroactive molecules such as ferrocene (Fc) and tetracyanoethylene (TCNE). Further, they showed that the ability to incorporate molecules within the pores also enables the synthesis of new crystalline phases and unlocks numerous applications, including gas sensing and photocatalysis, among others., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The first experimental investigation of a porous organic cage (POC) for the challenging task of H 2 S capture is reported. The N-containing cage molecular material, a tertiary amine POC (6FT-RCC3), demonstrates the highest H 2 S (hydrogen sulfide) capture (record capacity) for a porous material at room temperature and atmospheric pressure (20.6 mmol H 2 S g -1 ; 25 H 2 S molecules per cage) combined with excellent reversibility for at least five adsorption-desorption cycles. In situ FTIR spectroscopy, solid-state 13 C, and 15 N CP MAS NMR spectroscopy experiments are applied to investigate the adsorption mechanism, identifying relatively weak interactions via hydrogen bonding. In addition, the fluorescence performances of this POC material are evaluated for the detection and sensing of H 2 S, where a clear H 2 S selectivity is observed over other gases. Remarkably, the limit of detection (LOD) is calculated to be 0.13 mm (≈4.43 ppm) in a tetrahydrofuran (THF) solution of H 2 S., (© 2024 Wiley‐VCH GmbH.)

Diabetes mellitus (DM) prevalence is rising worldwide. Current therapies comprising subcutaneous insulin injections can cause adverse effects such as lipodystrophy, local reactions like redness and swelling, fluid retention, and allergic reactions. Nanoparticle carriers for oral insulin are groundbreaking compared to existing methods because they are non-invasive treatments, showing operational convenience, controlled release profile, and ability to simulate the physiological delivery route into the bloodstream. These systems improve patient adherence and have demonstrated the potential to lower blood glucose levels in DM. We present a systematic review and meta-analysis aimed at compiling relevant data to pave the way for developing innovative nano- and microparticles for the oral delivery of insulin. Our analysis of 85 articles revealed that the diminution of glucose levels is not proportional to the administered insulin dosage, which ranged from 1 to 120 International Units (IU). The meta-analysis data indicated that 25 IU of encapsulated porcine insulin did not produce a statistically significant outcome (p = 0.93). In contrast, a dosage of 30 IU was efficacious in eliciting an optimal hypoglycemic effect compared to excipient controls. Parameters such as a high degree of encapsulation (~ 90%), particle size (200-400 nm), and polydispersity index (0.086-0.3) are all associated with lower blood glucose levels. These parameters were also significant in the linear regression analysis. Among the excipients employed, chitosan emerged as a prevalent excipient in formulations due to its biocompatible and biodegradable properties and its ability to establish stable polymeric matrices. Even though oral insulin administration is a promising therapeutic method, it cannot guarantee preclinical safety and therapeutic efficacy yet in regulating glucose levels in diabetic conditions., Competing Interests: Declarations. Ethics approval and consent to participate: Not applicable. Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Metal-organic frameworks (MOFs), characterized by dynamic metal-ligand coordination bonding, have pivotal roles in catalysis, gas storage, and separation processes, owing to their open metal sites (OMSs). These sites, however, are frequently occupied by Lewis-base solvent molecules, necessitating activation to expose the OMSs for practical applications. Traditional thermal activation methods involve harsh conditions, risking structural integrity. This study presents a novel 'gas-flow activation' technique using inert gases like nitrogen and argon to eliminate these coordinating solvent molecules at low temperatures, thereby maintaining the structural integrity of MOFs. We specifically explored this method with HKUST-1, demonstrating that gas-flow activation at mild temperatures is not only feasible but also superior in efficiency compared to the conventional thermal methods. This approach highlights the potential for safer, more efficient activation processes in MOF applications, making it a valuable addition to the repertoire of MOF activation techniques. This activation function of inert gas flow allows HKUST-1 as a catalyst for the hydrogenation of acetophenone even at room temperature. In addition, it is demonstrated that this 'gas-flow activation' is broadly applicable in other MOFs such as MOF-14 and UTSA-76. Furthermore, the findings reveal that dynamic coordination bonding, the repeating transient dissociation-association of solvent molecules at OMSs, are key mechanisms in facilitating this activation, pointing towards new directions for designing activation strategies that prevent structural damage., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The novel bimetallic MOF, ZnCu-MOF-74, has been evaluated for the remediation of tetracycline-contaminated water. ZnCu-MOF-74 was obtained at room temperature, avoiding high pressure and temperature. ZnCu-MOF-74 exhibited chemical stability in the 4-8 pH range. The adsorption result analysis was described using the Elovich kinetic model and the Langmuir adsorption isotherm, suggesting a physicochemical process. The maximum adsorption capacity was estimated at 775.66 mg g -1 . The pH of the solution and the presence of ions such as NO 3 - , SO 4 2- , Na + , Mg 2+ , Cl - , and Ca 2+ had no influence on the removal of tetracycline. In addition, π-interactions and metal complexation were proposed as possible adsorption mechanisms through FT-IR and XPS. ZnCu-MOF-74 showed outstanding cyclability performance, preserving its adsorption capacity after 4 adsorption-desorption cycles, besides exhibiting chemical stability, proving the benefits of applying ZnCu-MOF-74 in the water treatment process.

The archetypical metal-organic framework (MOF), HKUST-1, has been systematically modified in both its organic and inorganic building blocks to introduce diversity in the metal centers and create defects within the network, achieving a variety of bimetallic hierarchical structures. These modifications changed the affinity of the MOFs for acid gases. The introduction of bimetallic sites mostly affects CO 2 adsorption, while the hierarchical structure generates an increase in SO 2 uptake capacity, allowing better performance in the separation of binary mixtures of these gases near room temperature. Notably, the synthesized HH-Cu 100 material exhibited an exceptionally high IAST SO 2 /CO 2 (10:90) selectivity of 3420 at 298 K, outperforming benchmark MOFs with open metal sites.

The continuous emission of harmful gases into the atmosphere damages the environment, air quality, and public health worldwide. To mitigate their impact, materials that capture and chemically inactivate gases are required; however, integrating and precisely controlling both abilities within a single material remains challenging. Herein, we demonstrate for the first time that switching between SO 2 -physisorption and chemisorption is possible for porous materials by using different counterions, as illustrated with a series of Pd 6 L 8 Metal-Organic Cages (MOCs). Pd-MOCs bearing BF 4 - , PF 6 - , or SO 4 2- expressed reversible adsorption (up to 3.6 mmol g -1 ), cyclability, and SO 2 /CO 2 selectivity. NO 3 - promoted conversion of SO 2 to sulfate, as corroborated with M 6 L 8 cages built on Co(II), Cu(II), and Zn(II) ions. Noteworthy, the nitrate derivative of Pd 6 L 8 captures 6.0 mmol g -1 of SO 2 , cleanly transforms it to SO 4 2- within its cavity in 94 % yield at room temperature, it is quantitatively regenerated, and tolerates humid SO 2 ; such qualities are unprecedented for SO 2 adsorbents. The deliberate use of counterions for modulating adsorption could be applied to charged MOFs, COFs, or POCs, potentially leading to the development of new reactivity or catalysis pathways for advanced applications against contaminant gases., (© 2024 Wiley-VCH GmbH.)

The article focuses on preparing a nanoformulation based on hydrotalcite and glycyrrhizic acid (GA), seeking a hepatoprotective effect. For this purpose, hydrotalcite-GA formulations were prepared by varying the following conditions to obtain optimal systems in terms of size and PDI (the lowest values), and Z potential (the highest values): (i) type of hydrotalcite (obtained by co-precipitation or calcined hydrotalcite); method used (ultrasound or high shear stirring), and (iii) type of stabilizer (Tween®80 or Pluronic® F-127). The best results were obtained using hydrotalcite obtained by co-precipitation, with high shear stirring and adding a stabilizer, either Tween®80 (HT-T80-GA: mean particle size = 315 nm, PDI = 0.18, Z potential = -20.93) or Pluronic® F-127 (HT-PF127-GA: mean particle size = 307 nm; PDI = 0.27, Z potential = -21.03). After stability studies, the HT-T80-GA formulation was chosen to study antioxidant activity, cytotoxicity, and intracellular penetration capacity. Although the hepatoprotective effect of GA in solution allowed a high viability and antioxidant activity, the fact of including GA in the HT-T80-GA formulation favored its penetration into hepatocytes, with a decrease in Caspase-3/7 expression of C-9 hepatocyte cells treated with H 2 O 2 , suggesting the capacity to inhibit apoptosis., Competing Interests: Declarations Ethics Approval and Consent to Participate Not applicable. Human and Animal Rights No animals/humans were used for studies that are the basis of this research. Conflict of Interest No potential conflict of interest was reported by the authors., (© 2024. The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.)

The development of adsorbents for air pollutant remediation and effective monitoring is of interest. Then, the effect of the APTES functionalization ratio on the impact of the adsorption and detection of SO 2 molecules was evaluated. The higher APTES functionalization material (SBA-15_6.1APTES) shows a high uptake of 1.15 mmol g -1 at 0.001 bar and 298 K. Fluorescence, time-resolved photoluminescence, and quantum yield experiments revealed a turn-on effect specifically for SO 2 molecules, indicating high selectivity, suggesting host-to-guest energy transfer. Attractively, XPS measurement provided an understanding of the mechanism, suggesting hydrogen bonding and dipole-dipole interactions as the main interactions between SO 2 molecules and SBA-15_6.1APTES. DFT calculations were performed to confirm these interactions. Furthermore, this study highlights the application of SBA-15 materials with different amino modifications for SO 2 treatment and provides insight into the interaction mechanism using experimental techniques.

Structure-porosity relationships for metal-organic polyhedra (MOPs) are hardly investigated because they tend to be amorphized after activation, which inhibits crystallographic characterization. Here, we show a mixed-ligand strategy to statistically distribute two distinct carbazole-type ligands within rhodium-based octahedral MOPs, leading to systematic tuning of the microporosity in the resulting amorphous solids.

SO 2 emissions not only affect local air quality but can also contribute to other environmental issues. Developing low-cost and robust adsorbents with high uptake and selectivity is needed to reduce SO 2 emissions. Here, we show the SO 2 adsorption-desorption capacity of carbon microfibers (CMFs) at 298 K. CMFs showed a reversible SO 2 uptake capacity (5 mmol g -1 ), cyclability over ten adsorption cycles with fast kinetics and good selectivity towards SO 2 /CO 2 at low-pressure values. Additionally, CMFs' photoluminescence response to SO 2 and CO 2 was evaluated.

Confinement is a very common phenomenon in chemistry, for example, when molecules are located inside cavities. In these conditions, the electronic structure of atoms and molecules is modified. These changes could be mapped through the interaction with other molecules since non-covalent interactions between molecules are also influenced by confinement. In this work we address both topics, non-covalent interactions, and confined systems, using quantum chemistry tools with new software, emphasizing the importance of analyzing both fields simultaneously.

The Al(III)-based MOF CYCU-3 exhibits a relevant SO 2 adsorption performance with a total uptake of 11.03 mmol g -1 at 1 bar and 298 K. CYCU-3 displays high chemical stability towards dry and wet SO 2 exposure. DRIFTS experiments and computational calculations demonstrated that hydrogen bonding between SO 2 molecules and bridging Al(III)-OH groups are the preferential adsorption sites. In addition, photoluminescence experiments demonstrated the relevance of CYCU-3 for application in SO 2 detection with good selectivity for SO 2 over CO 2 and H 2 O. The change in fluorescence performance demonstrates a clear turn-on effect after SO 2 interaction. Finally, the suppression of ligand-metal energy transfer along with the enhancement of ligand-centered π* → π electronic transition was proposed as a plausible fluorescence mechanism.

CsPbBr 3 nanocrystals (NCs) are promising optoelectronic and catalytic materials. Manipulating their morphology can improve their properties and stability. In this work, an alkene-derived zwitterionic ligand was used to control the morphology of CsPbBr 3 NCs to yield the highly unusual rhombicuboctahedron morphology, showcasing the first example of a surfactant-tail controlled growth.

Copper deficiency can trigger various diseases such as Amyotrophic Lateral Sclerosis (ALS), Parkinson's disease (PD) and even compromise the development of living beings, as manifested in Menkes disease (MS). Thus, the regulated administration (controlled release) of copper represents an alternative to reduce neuronal deterioration and prevent disease progression. Therefore, we present, to the best of our knowledge, the first experimental in vitro investigation for the kinetics of copper release from MOF-74(Cu) and its distribution in vivo after oral administration in male Wistar rats. Taking advantage of the abundance and high periodicity of copper within the crystalline-nanostructured metal-organic framework material (MOF-74(Cu)), it was possible to control the release of copper due to the partial degradation of the material. Thus, we simultaneously corroborated a low accumulation of copper in the liver (the main detoxification organ) and a slight increase of copper in the brain (striatum and midbrain), demonstrating that MOF-74(Cu) is a promising pharmacological alternative (controlled copper source) to these diseases., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Not only is excellent performance in SO 2 capture by porous materials (uptake above 17 mmol g -1 ) relevant, but also finding a correlation between the architecture changes into a family and their SO 2 adsorption is very useful. In this contribution, we studied the SO 2 adsorption behavior (at very low pressure) of an Al(III)-MOF family that shares the pore architecture of MIL-53. The results indicate an inversely proportional trend for the SO 2 capture and pore expansion, since by increasing the length of the channel pore, the SO 2 uptake gradually decreases. In addition, this trend is clearly observed in the heat of adsorption, which describes the interaction between the SO 2 molecule and the μ-OH functional group. These finding are supported by experimental analysis and computational studies.

Metal-organic frameworks (MOFs) provide uniquely tunable, periodic platforms for site-isolation of reactive low-valent metal complexes of relevance in modern catalysis, adsorptive applications, and fundamental structural studies. Strategies for integrating such species in MOFs include post-synthetic metalation, encapsulation and direct synthesis using low-valent organometallic complexes as building blocks. These approaches have each proven effective in enhancing catalytic activity, modulating product distributions (i.e., by improving catalytic selectivity), and providing valuable mechanistic insights. In this minireview, we explore these different strategies, as applied to isolate low-valent species within MOFs, with a particular focus on examples that leverage the unique crystallinity, permanent porosity and chemical mutability of MOFs to achieve deep structural insights that lead to new paradigms in the field of hybrid catalysis., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The recent development and implementation of copper-based metal-organic frameworks in biological applications are reviewed. The advantages of the presence of copper in MOFs for relevant applications such as drug delivery, cancer treatment, sensing, and antimicrobial are highlighted. Advanced composites such as MOF-polymers are playing critical roles in developing materials for specific applications.

A non-porous version of SU-101 (herein n-SU-101) was evaluated for the CO 2 cycloaddition reaction. The findings revealed that open metal sites (Bi 3+ ) are necessary for the reaction. n-SU-101 displays a high styrene oxide conversion of 96.6% under mild conditions (3 bar and 80 °C). The catalytic activity of n-SU-101 demonstrated its potential application for the cycloaddition of CO 2 using styrene oxide.

In the present work, nanocrystalline Zn-MOF-74 is shown to be a heterogeneous catalyst for the acid-catalyzed ring-opening alcoholysis of cyclohexene oxide. The results corroborated that accessible open metal sites within the material are critical conditions (Zn(ii) Lewis acid sites) for this reaction. Zn-MOF-74 was tested at three different temperatures (30, 40, and 50 °C) for the alcoholysis reaction. Furthermore, the cyclohexene oxide conversion was 94% in less than two days. A comparison of the catalytic activity with different crystal sizes of Zn-MOF-74 and the homogenous phase, zinc acetate, was conducted. Zn-MOF-74 exhibited excellent catalytic cyclability for three cycles without losing its activity. The material showed chemical stability by retaining its crystalline structure after the reaction and cyclability process., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Developing robust multifunctional metal-organic frameworks (MOFs) is the key to advancing the further deployment of MOFs into relevant applications. Since the first report of MFM-300(Sc) (MFM = Manchester Framework Material, formerly known as NOTT-400), the development of applications of this robust microporous MOF has only grown. In this review, a summary of the applications of MFM-300(Sc), as well as some emerging advanced applications, have been discussed. The adsorption properties of MFM-300(Sc) are presented systematically. Particularly, this contribution is focused on acid and corrosive gas adsorption. In addition, recent applications for catalysis based on the outstanding hemilabile Sc-O bond character are highlighted. Finally, some new research areas are introduced, such as host-guest chemistry and biomedical applications. This highlight aims to showcase the recent advances and the potential for developing new applications of this promising material.

Metal-organic framework (MOF)-based catalysts are outstanding alternative materials for the chemical transformation of greenhouse and toxic gases into high-add-value products. MOF catalysts exhibit remarkable properties to host different active sites. The combination of catalytic properties of MOFs is mentioned in order to understand their application. Furthermore, the main catalytic reactions, which involve the chemical transformation of CH 4 , CO 2 , NO x , fluorinated gases, O 3 , CO, VOCs, and H 2 S, are highlighted. The main active centers and reaction conditions for these reactions are presented and discussed to understand the reaction mechanisms. Interestingly, implementing MOF materials as catalysts for toxic gas-phase reactions is a great opportunity to provide new alternatives to enhance the air quality of our planet.

The MOF-type Ni 2 (dobpdc) shows a high chemical stability towards SO 2 , high capacity for SO 2 capture at low pressure (4.3 mmol g -1 at 298 K and up to 0.05 bar), and exceptional cycling performance. Fluorescence experiments demonstrated the SO 2 detection properties of Ni 2 (dobpdc) with a remarkable SO 2 detection selectivity. Finally, time-resolved photoluminescence experiments provided a plausible mechanism of SO 2 detection by this Ni(II)-based MOF material.

Encapsulating and protecting dopamine from oxidation is a difficult challenge. We propose to use SU-101 BioMOF as a dopamine host, where we study different adsorption scenarios by a robust computational approach. Our results show that dopamine encapsulation is feasible with the formation of non-covalent interactions within the SU-101 pores. These computational results have been corroborated experimentally.

The MOF material NU-1000 was employed to host Ni tripodal complexes prepared from new organometallic precursors [HNi( κ 4 ( E , P , P , P )-E( o -C 6 H 4 CH 2 PPh 2 ) 3 ], E = Si (Ni-1), Ge (Ni-2). The new heterogeneous catalytic materials, Ni-1@NU-1000 and Ni-2@NU-1000, show the advantages of both homogeneous and heterogeneous catalysts. They catalyze the hydroboration of aldehydes and ketones more efficiently than the homogeneous Ni-1 and Ni-2, under aerobic conditions and show recyclability.

Modulated self-assembly protocols are used to develop facile, HF-free syntheses of the archetypal flexible PCP, MIL-53(Cr), and novel isoreticular analogues MIL-53(Cr)-Br and MIL-53(Cr)-NO 2 . All three PCPs show good SO 2 uptake (298 K, 1 bar) and high chemical stabilities against dry and wet SO 2 . Solid-state photoluminescence spectroscopy indicates all three PCPs exhibit turn-off sensing of SO 2 , in particular MIL-53(Cr)-Br, which shows a 2.7-fold decrease in emission on exposure to SO 2 at room temperature, indicating potential sensing applications.

A rich plethora of information about grafted chitosan (CS) for medical use has been reported. The capability of CS-grafted poly(N-hydroxyethyl acrylamide) (CS-g-PHEAA) to support human dermal fibroblasts (HDFs) in vitro has been proven. However, CS-grafted copolymers lack good stiffness and the characteristic microstructure of a cellular matrix. In addition, whether CS-g-PHEAA can be used to prepare a scaffold with a suitable morphology and mechanical properties for skin tissue engineering (STE) is unclear. This study aimed to show for the first time that step-growth polymerizations can be used to obtain polyurethane (PU) platforms of CS-g-PHEAA, which can also have enhanced microhardness and be suitable for in vitro cell culture. The PU prepolymers were prepared from grafted CS, polyethylene glycol, and 1,6-hexamethylene diisocyanate. The results proved that a poly(saccharide-urethane) [(CS-g-PHEAA)-PU] could be successfully synthesized with a more suitable microarchitecture, thermal properties, and topology than CS-PU for the dynamic culturing of fibroblasts. Cytotoxicity, proliferation, histological and immunophenotype assessments revealed significantly higher biocompatibility and cell proliferation of the derivative concerning the controls. Cells cultured on (CS-g-PHEAA)-PU displayed a quiescent state compared to those cultured on CS-PU, which showed an activated phenotype. These findings may be critical factors in future studies establishing wound dressing models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Classical multicomponent reactions (MCRs) are domino-type one-pot processes in which three or more different reactants are combined sequentially in the same reactor to synthesize compounds containing all or almost all atoms coming from the reactants. Besides, pseudo-MCRs are also domino-type one-pot processes involving combinations of at least three reactants but in which at least one of them takes part in two or more reaction steps. In consequence, the products synthesized through pseudo-MCRs contain also all or almost all atoms but coming from two or more identical reactants. Thus, pseudo-MCRs differ from classical MCRs because the first ones appear to involve an assembly of a higher number of different components than those that are being truly assembled. However, pseudo-MCRs are also useful synthetic tools to generate libraries of complex compounds in few experimental steps, and although the repeated reactants may make them appear less diverse than classical MCRs, this can be offset by the higher number of reactants that can participate in this type of reaction. Overall, there are two types of pseudo-MCRs. The first are those in which the duplicated reagents participate in different steps of the corresponding reaction mechanism. The second kind of pseudo-MCRs are those in which one or more components react simultaneously with a main reagent containing two or more identical functional groups. These latter are known as repetitive pseudo-MCRs. Thus, the aim of the present review is to cover for the first time selected works mainly published in the last two decades about pseudo-MCRs and their repetitive versions toward the synthesis of novel, complex, and highly symmetrical molecules, often including their interesting applications in various fields of science and technology. The manuscript has been categorized considering the number of reagents participating in the corresponding pseudo-MCRs, aiming to give readers novel insights for their future investigations., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

MFM-300(Sc) was explored as a catalyst for the gas-phase hydrogenation of acetone. The catalysis results support the presence of non-permanent open Sc(III) sites within the structure due to the requirement of Lewis acid sites for the reaction to proceed. The open Sc(III) sites are generated in situ due to the presence of hemilabile Sc-O bonds. MFM-300(Sc) showed high mechanical and chemical stability, and the crystalline structure was maintained after the catalytic reaction. The catalytic activity of the material was quantified by performing a gas-phase reaction using a continuous flow reactor. The acetone conversion in MFM-300(Sc) was estimated to be 27.7% with no loss of activity after catalytic cycles.

Metal-organic frameworks have developed into a formidable heterogeneous catalysis platform in recent years. It is well established that thermolysis of coordinated solvents from MOF nodes can render highly reactive, coordinatively unsaturated metal complexes which are stabilized via site isolation and serve as active sites in catalysis. Such approaches are limited to frameworks featuring solvated transition-metal complexes and must be stable toward the formation of "permanent" open metal sites. Herein, we exploit the hemilability of metal-carboxylate bonds to generate transient open metal sites in an In(III) MOF, pertinent to In-centered catalysis. The transient open metal sites catalyze the Strecker reaction over multiple cycles without loss of activity or crystallinity. We employ computational and spectroscopic methods to confirm the formation of open metal sites via transient dissociation of In(III)-carboxylate bonds. Furthermore, the amount of transient open metal sites within the material and thus the catalytic performance can be temperature-modulated.

The SO 2 capture performance of MIL-53(Al)-TDC was optimised by confining a small amount of MeOH within its pores (MeOH@MIL-53(Al)-TDC). In comparison with fully activated MIL-53(Al)-TDC, MeOH@MIL-53(Al)-TDC shows a 39% higher SO 2 capture capacity. Monte Carlo simulations revealed that such an enhancement is associated with an increase in the degree of confinement via the SO 2 molecules resulting from the formation of a lump (MeOH molecules) in the vicinity of the μ-OH groups.

Linezolid (LNZ) is a new-generation synthetic molecule for the antibacterial treatment of severe infections, particularly in infective cases where the bacterial resistance to first-choice drugs is caused by Gram-positive pathogens. In this context, since 2009, some strains resistant to LNZ in patients with long-term treatments have been reported. Therefore, there is a need to use not only new drug molecules with antibacterial activities in the dosage form but also a different approach to pharmacotherapeutic strategies for skin infections, which lead to a reduction in the concentration of biocides. This work explores LNZ hosted at two isostructural MOFs, MOF-74(Zn) and MOF-74(Cu), as promising antimicrobial systems for gradual biocide release within 6 h. These systems reach a lower minimum inhibitory concentration (MIC) in comparison to free LNZ. Even a decreased MIC value is also observed, which is an encouraging result regarding the efficiency of the systems to control concentration-dependent antimicrobial resistance.

The SO 2 adsorption-desorption capacity at room temperature and 1 bar of the metal-organic polyhedron MOP-CDC was investigated. In addition, the qualitative solid-state absorption-emission properties of this material (before and after SO 2 exposure) were measured and tested, and it demonstrated remarkable capability for SO 2 detection. Our results represent the first example of fluorimetric SO 2 detection in a MOP.

Uncommon reversible guest-induced metal-hemilabile linker bond dynamics in MOF MFM-300(Sc) was unraveled to switch on/switch off catalytic open metal sites. The catalytic activity of this MOF with non-permanent open metal sites was demonstrated using a model Strecker hydrocyanation reaction as a proof-of-concept. Conclusively, the catalytic activity was evidenced to be fully reversible, preserving the conversion performance and structure integrity of MFM-300(Sc) over multiple cycles. These experimental findings were corroborated by quantum-calculations that revealed a reaction mechanism driven by the Sc-open metal sites. This discovery paves the way towards the design of new effective and easily regenerable heterogeneous MOF catalysts integrating switchable metal sites., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The design of controlled grafting copolymers is critical in synthesizing effective artificial cellular matrices because of their regulatory role in cellular behavior. However, it is unclear whether poly(2-aminoethyl methacrylate) grafted onto chitosan generated by gamma-radiation-induced graft polymerization in different solvents can influence the physicochemical properties and biotech applicability of the copolymer. This work aims to demonstrate for the first time the effect of various solvents on the synthesis, properties, and biological performance of grafted chitosan using the simultaneous irradiation method. The results proved that the solvent is one of the critical factors affecting the properties of the modified polysaccharide. The degree of grafting showed a solvent-dependent profile. Hexane presented utmost importance concerning the degree of grafting. Ethyl acetate showed the best results in grafting extent and human dermal fibroblast growth. These findings indicate that proper solvent selection determines the possible copolymer use for in vitro engineered skin substitute models., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Gold nanoparticles (AuNPs) present unique physicochemical characteristics, low cytotoxicity, chemical stability, size/morphology tunability, surface functionalization capability, and optical properties which can be exploited for detection applications (colorimetry, surface-enhanced Raman scattering, and photoluminescence). The current challenge for AuNPs is incorporating these properties in developing more sensible and selective sensing methods and multifunctional platforms capable of controlled and precise drug or gene delivery. This review briefly highlights the recent progress of AuNPs in biomedicine as bio-sensors and targeted nano vehicles.

The environmentally benign metal-organic framework (MOF) CUK-1 based on 2,4-pyridine dicarboxylate has been prepared for the first time using Mn(II) as the inorganic node and water as the only solvent. Mn-CUK-1 shows reversible and efficient capture of H 2 O, SO 2 , and H 2 S. Compared to previously studied Co(II) and Mg(II) versions of the same MOF, Mn-CUK-1 also exhibited unique temperature-induced structural flexibility due to organic linker torsion, as detailed by variable-temperature single-crystal X-ray diffraction studies. Owing to this inherent solid-state flexibility, Mn-CUK-1 showed stepwise adsorption for polar gases, which induce structural deformations upon adsorption, while the nonpolar guest adsorbates were reversibly sorbed in a more classical manner. Notably, Mn-CUK-1 demonstrates the highest reported H 2 S capacity-to-surface area ratio among MOFs that are chemically stable toward this reactive acidic molecule. Moreover, Mn-CUK-1 displays exceptional structural stability in the presence of high relative humidity and corrosive gases and shows soft crystalline behavior triggered by changes in both the adsorption temperature and guest molecule identity.

Two fluorinated γ-Al 2 O 3 series were synthesized by a sol-gel method with two solvents (2-propanol and 2-butanol), two aluminium sources (ATB and ATP) and one fluorine source (Na 3 AlF 6 ). The resulting inorganic matrixes were evaluated to characterize aluminium and fluorine species ([AlO 4 5- ], [AlO 5 7- ], [AlO 6 9- ], [AlF 4 - ], [AlF 5 2- ] and [AlF 6 3- ]) by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), 27 Al magic angle spinning nuclear magnetic resonance ( 27 Al MAS-NMR) and infrared spectroscopy (IR-ATR). BET and BJH analyses using the nitrogen isotherms of these materials allowed identifying a clear trend in some textural parameters such as specific surface area and fluorine content. These results were confirmed by scanning electron microscopy (SEM). Chemical affinity and acid surface properties were evidenced with colour shifts in two groups of hybrid pigments, prepared with natural anthocyanins ( Brassica oleracea ) and betacyanins ( Bougainvillea glabra ).

There is growing interest in metal-organic cages (MOCs) as porous materials owing to their processability in solution. The discrete molecular character and surface features of MOCs have a direct impact on the interactions between cages, enabling the final physical state of the materials to be tuned. In this tutorial review, we discuss how to use MOCs as core building units, highlighting the role played by surface functionalisation of MOCs in leading to porous materials in a range of states covering crystalline solids, soft matter, liquids and composites. We finish by providing an outlook on the opportunities for this work to serve as a foundation for the development of increasingly complex functional porous materials structured over various length scales.

Capture, storage and subsequent controlled release or transformation of sulfur dioxide (SO 2 ) in mild conditions is still a challenge in the material science field. Recent advances in the use of porous materials have demonstrated good SO 2 capture, particularly in metal-organic frameworks (MOFs), metal-organic cages (MOCs), and porous organic cages (POCs). The striking feature of these porous materials is the high SO 2 uptake capacity in reversible settings. A partially fluorinated MIL-101(Cr) is stand-alone material with the highest SO 2 uptake in chemically stable MOFs. Likewise, metal-free adsorbents like POCs exhibits a reversible SO 2 uptake behavior. The SO 2 adsorption characteristics of these three structurally and functionally unique adsorbent systems are highly dependent on the binding sites and mode of binding of SO 2 molecules. This Review has highlighted the preferential binding sites in these materials to give a full perspective on the field. We anticipate that it will offer valuable information on the progress made towards improving SO 2 capture by hybrid systems., (© 2022 Wiley-VCH GmbH.)

Scandium(III) ions can form robust metal-organic frameworks (MOFs) with relative ease of synthesis. However, their use in MOF construction remains scarce compared to the vast collection of MOFs using other ions. This highlight features the chronological development of Sc(III)-MOFs, which attest to the ability of Sc(III) ions to afford materials that combine exceptional stability with catalytic or photo-physical attributes.