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In this study, we designed three promising platforms based on metal–organic frameworks (MOFs) to develop paper-based analytical devices (PADs) for biosensing applications. PADs have become increasingly popular in field sensing in recent years due to their portability, low cost, simplicity, efficiency, fast detection capability, excellent sensitivity, and selectivity. In addition, MOFs are excellent choices for developing highly sensitive and selective sensors due their versatility for functionalizing, structural stability, and capability to adsorb and desorb specific molecules by reversible interactions. These materials also offer the possibility to modify their structure and properties, making them highly versatile and adaptable to different environments and sensing needs. In this research, we synthesized and characterized three different amino-functionalized MOFs: UiO-66-NH2 (Zr), MIL-125-NH2 (Ti), and MIL-101-NH2 (Fe). These MOFs were used to fabricate PADs capable of sensitive and portable monitoring of alkaline phosphatase (ALP) enzyme activity by laser-induced fluorescence (LIF). Overall, amino-derivated MOF platforms demonstrate significant potential for integration into biosensor PADs, offering key properties that enhance their performance and applicability in analytical chemistry and diagnostics. [ABSTRACT FROM AUTHOR]

Nanotechnology has emerged as a cornerstone in contemporary research, marked by the advent of advanced technologies aimed at nanoengineering materials with diverse applications, particularly to address challenges in human health. Among these challenges, antimicrobial resistance (AMR) has risen as a significant and pressing threat to public health, creating obstacles in preventing and treating persistent diseases. Despite efforts in recent decades to combat AMR, global trends indicate an ongoing and concerning increase in AMR. The primary contributors to the escalation of AMR are the misuse and overuse of various antimicrobial agents in healthcare settings. This has led to severe consequences not only in terms of compromised treatment outcomes but also in terms of substantial financial burdens. The economic impact of AMR is reflected in skyrocketing healthcare costs attributed to heightened hospital admissions and increased drug usage. To address this critical issue, it is imperative to implement effective strategies for antimicrobial therapies. This comprehensive review will explore the latest scientific breakthroughs within the metal–organic frameworks and the use of mesoporous metallic oxide derivates as antimicrobial agents. We will explore their biomedical applications in human health, shedding light on promising avenues for combating AMR. Finally, we will conclude the current state of research and offer perspectives on the future development of these nanomaterials in the ongoing battle against AMR. [ABSTRACT FROM AUTHOR]

This study addressed the formation of co‐crystals from Quercetin and Curcumin by mechanochemical treatment employing ball mill grinding. The binary system was initially studied using molecular complementarity and hydrogen bond propensity analysis structural tools available in Mercury software. This study was performed from CCDC reported structural data for Curcumin and Quercetin dihydrate used as starting reagents. Reaction conditions, such as Quercetin: Curcumin molar ratio, grinding time, and solvent‐assisted variables, were optimised to synthesise a new solid phase from the binary system. The synthesised product was characterised by differential scanning calorimetry, thermogravimetric analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and powder X‐ray diffraction techniques. Finally, to compare the anti‐oxidant capacities from the pure components, eutectic mixtures previously reported and the new crystalline phase was evaluated in vitro using the 1,1‐diphenyl‐2‐pycril‐hydrazylhydrate radical inhibition method. The co‐crystal phase and eutectic mixtures present higher anti‐oxidant activity with values around 5.0 mg/L compared to pure Quercetin (3,444 mg/L) and Curcumin (9,141 mg/L), using only half of the molecules. These results indicate Quercetin molecule is synergically active with the Curcumin molecule in the binary mixtures. [ABSTRACT FROM AUTHOR]

Three principal factors may influence the final structure of coordination polymers (CPs): (i) the nature of the ligand, (ii) the type and coordination number of the metal center, and (iii) the reaction conditions. Further, flexible carboxylate aliphatic ligands have been widely employed as building blocks for designing and synthesizing CPs, resulting in a diverse array of materials with exciting architectures, porosities, dimensionalities, and topologies as well as an increasing number of properties and applications. These ligands show different structural features, such as torsion angles, carbon backbone number, and coordination modes, which affect the desired products and so enable the generation of polymorphs or crystalline phases. Additionally, due to their large coordination numbers, using 4f and 5f metals as coordination centers combined with aliphatic ligands increases the possibility of obtaining different crystal phases. Additionally, by varying the synthetic conditions, we may control the production of a specific solid phase by understanding the thermodynamic and kinetic factors that influence the self-assembly process. This revision highlights the relationship between the structural variety of CPs based on flexible carboxylate aliphatic ligands and f-elements (lanthanide and actinides) and their outstanding luminescent properties such as solid-state emissions, sensing, and photocatalysis. In this sense, we present a structural analysis of the CPs reported with the oxalate ligand, as the one rigid ligand of the family, and other flexible dicarboxylate linkers with –CH2– spacers. Additionally, the nature of the luminescence properties of the 4f or 5f-CPs is analyzed, and finally, we present a novel set of CPs using a glutarate-derived ligand and samarium, with the formula [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2]•(2,2′-bipy) (α-Sm) and [2,2′-bipyH][Sm(HFG)2 (2,2′-bipy) (H2O)2] (β-Sm). [ABSTRACT FROM AUTHOR]

Coordination networks (CNs) with tailorable multi‐metallic composition were designed and then used as sacrificial materials to obtain promising materials with Up‐conversion (UC) properties. The metal‐organic precursors led to solid solutions of Rare‐Earth Oxides (REO)Y2O3:Yb3+/Er3+ or Y2O3:Yb3+/Er3+/Gd3 through a calcination process. In order to obtain luminescent UC platforms, spin‐coating technique was implemented to deposit these materials onto glass supports. The synthesized solids and the resulting films were characterized by Scanning Electron Microscopy – Energy Dispersive Spectroscopy (SEM‐EDS), infrared spectroscopy, powder (PXRD), and grazing incidence (GIXRD) X‐ray diffraction techniques. Moreover, the photophysical properties of bulk and deposited Y2O3:Ln3+ doped oxides were evaluated after being irradiated with NIR wavelength (980 nm) laser to excite the Yb3+ sensitizer ion. Besides, decay emission profiles from each sample were also obtained and lifetime (τobs) values were calculated. These results open up the implementation of REO thin films obtained through CN calcination for promising applications such as solar cells and sensor devices. [ABSTRACT FROM AUTHOR]

Two lanthanide doped nanosystems Ca0.8Ln0.1Na0.1WO4 (Ln = Eu, Sm), denoted as Eu@CWO and Sm@CWO, were prepared by a "top-down" approach in three simple steps: activation, miniaturization by high-energy milling, and further calcination. The solids were thoroughly characterized by X-ray powder diffraction (XRPD) and Scanning-electron microscopy (SEM). Also, analyses of the structure of the compounds and the impact of milling on the crystallite shape and size were carried out through Rietveld refinements. Solid-state photoluminescence was studied in terms of excitation, emission, lifetimes (τobs) and europium-quantum yields. Finally, the Eu@CWO sample was employed as a potential water-stable chemical sensor towards toxic cations, showing a quenching effect in the presence of iron ions. [ABSTRACT FROM AUTHOR]

The intense development that Metal‐Organic Frameworks have experienced along the last two decades, reflects the interest on these compounds as a new generation of multifunctional materials with diverse applications. The first works of Prof. Omar Yaghi devoted to obtain open frameworks by combining rigid aromatic linkers and a variety of metal centers, encouraged the creativity of the scientific community to designcoordination polymers employing aliphatic ligands as multitopic building blocks. Here, a revision of the literature dedicated to rare earth coordination networks mainly based in succinate ligand and derivatives is performed. A structural analysis of 2D and 3D frameworks based on rare earth elements and succinate, was carried out considering their inner connectivities and topologies with focus on those compounds with potential photoluminescent and catalytic technological applications. Thus, a variety of optical behaviours regarding the emission mechanisms, colours, lifetimes, quantum yields as well as chemical/thermal sensing properties are presented and compared with related phases found in literature. The catalytic performance of several rare earth‐succinates in three important reactions is discussed in terms of their acidity, dimensionality and available active centers towards the formation of the desired products analysing parameters such as selectivity, yields and TOFs. [ABSTRACT FROM AUTHOR]

Two series of metal–organic frameworks (MOFs) based on a flexible ligand and trivalent lanthanides were obtained hydrothermally in order to explore their optical properties at low temperature, magnetism, and catalytic activity in relation to their structural features. A multisite analysis was performed according to the 4f–4f transitions. Moreover, the heterogeneous catalytic activity of the series was evaluated in one‐pot cyanosilylation with benzaldehyde as substrate. Recyclability, structure conservation, and catalytic efficiency were also evaluated and compared with those of analogous compounds. [ABSTRACT FROM AUTHOR]

A new isostructural family of layered coordination networks (CNs) based on rare earth elements and mixed ligands was hydrothermally synthesized and fully characterized. The set of compounds with the general formula [REE(Salicylate)(Succinate)0.5(H2O)] (with REE = Ho or Y) belong to the monoclinic P21/c space group. Top-down methods were implemented in order to obtain nano-sized CN particles for potential application in thin film fabrication. The solid state photoluminescence (SSPL) of the Eu, Tb and Eu/Tb doped samples was explored in terms of excitation/emission spectra, lifetime values and quantification of light emission by the CIE chromaticity calculation. Measurement of the triplet state energy of the ligand at low temperature was carried out by analysing the SSPL of the Y-based compound; energy transfer pathways were studied. According to the high performance of the Tb-doped compound as a green emitter, thermal and chemical sensing assays were carried out. [ABSTRACT FROM AUTHOR]

Luminescent 3D metal-organic frameworks (MOFs) constructed from trivalent lanthanides Nd3+, Sm3+, Eu3+, Gd3+, Tb3+ and a flexible ligand, 2-methylsuccinate, (Ln-msucc) have been hydrothermally obtained as polycrystalline solids. They were fully characterized by X-ray powder diffraction, thermal analysis, vibrational spectroscopy, and scanning electron microscopy. The crystalline structure and topological features were elucidated and compared with those of related Ln-MOFs. The magnetic studies reveal that Nd-msucc and Gd-msucc present antiferromagnetic and ferromagnetic behavior, respectively. Moreover, the solid-state photoluminescence properties of all the compounds were fully explored. Depending on the lanthanide content, these materials exhibited luminescence in the near-infrared and visible regions. In particular, the photophysical behavior of the Eu phase was exhaustively examined and the radiative and nonradiative constants and intrinsic quantum yields were calculated. The hypersensitive nature of the Eu3+ 5D0→7F2 transition allowed an in-depth study of the optical response in the presence of various protic and aprotic solvents. As far as we know, the chemical-sensing studies employing Eu-msucc constitute the first case reported for a lanthanide succinate-derived framework. The obtained results are promising for the elaboration of specific chemical sensors based on this material. [ABSTRACT FROM AUTHOR]

A luminescent lanthanide metal-organic framework (MOF) based on Eu3+ and Tb3+ ions with 2-phenylsuccinate (EuTb-psa) was obtained solvothermally to explore its behavior as a temperature sensor in an unconventional temperature range through the study of the thermal evolution of the hypersensitive 4f-4f 5D0→7F2 transition and the luminescence lifetime. The efficiency of the luminescence process was evaluated through the europium intrinsic quantum yield ( QEu), and its variation as a function of temperature is also reported. The optical properties of four isostructural compounds (Pr-psa, Nd-psa, Gd-psa, and Tb-psa) were investigated and compared with those of related compounds. The energy of the triplet state of the ligand was also estimated. The samples were fully characterized by single-crystal and powder X-ray diffraction, thermal analysis, and vibrational spectroscopy. The heterogeneous catalytic activities of a series of Ln-psa MOFs (with Ln = Sm, Eu, Gd, Tb, EuGd, and EuTb) were evaluated in a one-pot cyanosilylation with benzaldehyde as the substrate. [ABSTRACT FROM AUTHOR]

Reactionsin aqueous solution under hydrothermal conditions between(±)-2,3-dimethylsuccinic acid and lanthanide chlorides lead totwo different isostructural types with chemical formulas [Ln2(C6H8O4)3(H2O)2] Ln(III) = Pr–Eu (exceptPm) (Type I, compounds 1–4) and [Ln2(C6H8O4)3] Ln(III) = Tb–Yb (except Tm) (Type II, compounds 5–9). The crystal structure has been solvedfor the Pr (1)-, Sm (3)-, and Ho (7)-containing compounds by means of single-crystal XRD methods,whereas powder XRD Rietveld refinement was used for the rest of theMOFs. Compounds 1–4crystallize inthe triclinic space group P1̅, whereas compounds 5–9belong to the tetragonal space group P43212. Type I and II compounds are3D frameworks consisting of chains of [LnO8(H2O)] or [LnO8] polyhedra, respectively, linked bydimethylsuccinate anions, giving rise to I1O2connectivity. All the compounds were characterized by X-ray diffraction,variable-temperature Fourier transform infrared spectroscopy, andthermal analysis. An exhaustive topological study was performed incomparison with other related compounds. The photoluminescent (PL)properties for compounds 3, 4, and 5have been also explored, indicating that a metal-centeredluminescent process takes place. [ABSTRACT FROM AUTHOR]

Since the first studies of luminescent sensors based on metal organic frameworks (MOFs) about ten years ago, there has been an increased interest in the development of specific sensors towards cations, anions, explosives, small molecules, solvents, etc. However, the detection of toxic compounds related to agro-industry and nuclear activity is noticeably scarce or even non-existent. In this work, we report the synthesis and characterization of luminescent lanthanide-based MOFs (Ln-MOFs) with diverse crystalline architectures obtained by solvothermal methods. The luminescent properties of the lanthanides, and the hypersensitive transitions of Eu3+ (5D0→7F2) and Tb3+ (5D4→7F5) intrinsically found in the obtained MOFs in particular, were evaluated and employed as chemical sensors for agrochemical and cationic species. The limit of detection (LOD) of Tb-PSA MOFs (PSA = 2-phenylsuccinate) was 2.9 ppm for [UO22+] and 5.6 ppm for [Cu2+]. The variations of the 4f–4f spectral lines and the quenching/enhancement effects of the Ln-MOFs in the presence of the analytes were fully analyzed and discussed in terms of a combinatorial "host–guest" vibrational and "in-silico" interaction studies. [ABSTRACT FROM AUTHOR]