A Mesoporous Gd-MOF with Lewis Basic Sites for 5-Fu Delivery and Inhibition of Human Lung Cancer Cells In Vivo and In Vitro

Crystal structure and characterization of a new lanthanide coordination polymer, [Pr2(pydc)(phth)2(H2O)3]·H2O

A new lanthanide coordination polymer, poly[[tri-aqua-bis-(μ4-phthalato)(μ3-pyridine-2,5-di-carboxyl-ato)dipraseodymium] monohydrate], {[Pr2(C7H3NO4)2(C8H4O4)(H2O)3]·H2O}n or {[Pr2(phth)2(pydc)(H2O)3]·H2O}n, (pydc2- = pyridine-2,5-di-carboxyl-ate and phth2- = phthalate) was synthesized and characterized, revealing the structure to be an assembly of di-periodic {Pr2(pydc)(phth)2(H2O)3}n layers. Each layer is built up by edge-sharing {Pr2N2O14} and {Pr2O16} dimers, which are connected through a new coordin-ation mode of pydc2- and phth2-. These layers are stabilized by inter-nal hydrogen bonds and π-π inter-actions. In addition, a three-dimensional supra-molecular framework is built by inter-layer hydrogen-bonding inter-actions involving the non-coordinated water mol-ecule. Thermogravimetric analysis shows that the title compound is thermally stable up to 400°C.

A reliable QSPR model for predicting drug release rate from metal-organic frameworks: a simple and robust drug delivery approach

During the drug release process, the drug is transferred from the starting point in the drug delivery system to the surface, and then to the release medium. Metal-organic frameworks (MOFs) potentially have unique features to be utilized as promising carriers for drug delivery, due to their suitable pore size, high surface area, and structural flexibility. The loading and release of various therapeutic drugs through the MOFs are effectively accomplished due to their tunable inorganic clusters and organic ligands. Since the drug release rate percentage (RES%) is a significant concern, a quantitative structure-property relationship (QSPR) method was applied to achieve an accurate model predicting the drug release rate from MOFs. Structure-based descriptors, including the number of nitrogen and oxygen atoms, along with two other adjusted descriptors, were applied for obtaining the best multilinear regression (BMLR) model. Drug release rates from 67 MOFs were applied to provide a precise model. The coefficients of determination (R2) for the training and test sets obtained were both 0.9999. The root mean square error for prediction (RMSEP) of the RES% values for the training and test sets were 0.006 and 0.005, respectively. To examine the precision of the model, external validation was performed through a set of new observations, which demonstrated that the model works to a satisfactory degree.

BioMOF-Based Anti-Cancer Drug Delivery Systems

A variety of nanomaterials have been developed specifically for biomedical applications, such as drug delivery in cancer treatment. These materials involve both synthetic and natural nanoparticles and nanofibers of varying dimensions. The efficacy of a drug delivery system (DDS) depends on its biocompatibility, intrinsic high surface area, high interconnected porosity, and chemical functionality. Recent advances in metal-organic framework (MOF) nanostructures have led to the achievement of these desirable features. MOFs consist of metal ions and organic linkers that are assembled in different geometries and can be produced in 0, 1, 2, or 3 dimensions. The defining features of MOFs are their outstanding surface area, interconnected porosity, and variable chemical functionality, which enable an endless range of modalities for loading drugs into their hierarchical structures. MOFs, coupled with biocompatibility requisites, are now regarded as highly successful DDSs for the treatment of diverse diseases. This review aims to present the development and applications of DDSs based on chemically-functionalized MOF nanostructures in the context of cancer treatment. A concise overview of the structure, synthesis, and mode of action of MOF-DDS is provided.

Crystal structure and photoluminescent properties of a new EuIII–phthalate–acetate coordination polymer

The crystal structure of a new one-dimensional [Eu^III(phth)(OAc)(H₂O)] coordination polymer and its room-temperature photoluminescent properties are reported.

A new coordination polymer, poly[(acetato)aqua(μ₃-phthalato)europium(III)], [Eu(C₈H₄O₄)(CH₃O₂)(H₂O)]_n or [Eu^III(phth)(OAc)(H₂O)] (phth²⁻ = phthalate and OAc⁻ = acetate) was synthesized and characterized, revealing it to be a supra­molecular assembly of one-dimensional [Eu^III(phth)(OAc)(H₂O)] chains. Each chain is built up of edge-sharing distorted tricapped trigonal–prismatic TPRS-{Eu^IIIO₉} building motifs and assembled in a regular fashion through hydrogen-bonding and aromatic π–π inter­actions. The fully deprotonated phth²⁻ ligand was shown to be an effective sensitizer, promoting the characteristic ⁵D₀→⁷F_J (J = 1–4) emissions of Eu^III even in the presence of the non-sensitizing OAc⁻ group.

Effect of Different Synthesis Approaches on Structural and Thermal Properties of Lanthanide(III) Metal–Organic Frameworks Based on the 1H-Pyrazole-3,5-Dicarboxylate Linker

The impact of different synthetic procedures such as: hydrothermal, mechanochemical and precipitation on the structure and thermal properties of coordination polymers of 1H-pyrazole-3,5-dicarboxylic acid (H3pdca) with selected lanthanide ions was determined. The prepared complexes of the general formula: Ln2(Hpdca)3⋅nH2O, where Ln = Eu(III), Nd(III), Tb(III) and Er(III); n = 6 or 7 were fully investigated by: elemental analysis, Energy-Dispersive X-Ray (ED-XRF) and infrared (ATR-FTIR) spectroscopy, powder as well as single-crystal X-ray diffraction methods and thermal analysis (TG-DSC and TG-FTIR) in various atmospheres. It was proved that all used strategies offer high yields of reactions along with crystallinity of the obtained products. The X-ray diffraction methods allowed to conclude that the complexes with the same metal ions exhibit the same crystal structure despite different synthesis routes. On the other hand, the coordination polymers of Eu(III), Tb(III) and Er(III) prepared under different conditions are isomorphous. Only neodymium(III) compounds have a different crystal structure. Thermal stability of the produced complexes was correlated with the synthesis conditions, in particular with the way of energy supply. It was found that the highest thermal stability was exhibited by the complexes prepared under the hydrothermal conditions. Additionally, based on the volatile products of metal complexes decomposition, the mechanism of their pyrolysis was proposed in relation to their structures.

Onco-Receptors Targeting in Lung Cancer via Application of Surface-Modified and Hybrid Nanoparticles: A Cross-Disciplinary Review

Lung cancer is among the most prevalent and leading causes of death worldwide. The major reason for high mortality is the late diagnosis of the disease, and in most cases, lung cancer is diagnosed at fourth stage in which the cancer has metastasized to almost all vital organs. The other reason for higher mortality is the uptake of the chemotherapeutic agents by the healthy cells, which in turn increases the chances of cytotoxicity to the healthy body cells. The complex pathophysiology of lung cancer provides various pathways to target the cancerous cells. In this regard, upregulated onco-receptors on the cell surface of tumor including epidermal growth factor receptor (EGFR), integrins, transferrin receptor (TFR), folate receptor (FR), cluster of differentiation 44 (CD44) receptor, etc. could be exploited for the inhibition of pathways and tumor-specific drug targeting. Further, cancer borne immunological targets like T-lymphocytes, myeloid-derived suppressor cells (MDSCs), tumor-associated macrophages (TAMs), and dendritic cells could serve as a target site to modulate tumor activity through targeting various surface-expressed receptors or interfering with immune cell-specific pathways. Hence, novel approaches are required for both the diagnosis and treatment of lung cancers. In this context, several researchers have employed various targeted delivery approaches to overcome the problems allied with the conventional diagnosis of and therapy methods used against lung cancer. Nanoparticles are cell nonspecific in biological systems, and may cause unwanted deleterious effects in the body. Therefore, nanodrug delivery systems (NDDSs) need further advancement to overcome the problem of toxicity in the treatment of lung cancer. Moreover, the route of nanomedicines’ delivery to lungs plays a vital role in localizing the drug concentration to target the lung cancer. Surface-modified nanoparticles and hybrid nanoparticles have a wide range of applications in the field of theranostics. This cross-disciplinary review summarizes the current knowledge of the pathways implicated in the different classes of lung cancer with an emphasis on the clinical implications of the increasing number of actionable molecular targets. Furthermore, it focuses specifically on the significance and emerging role of surface functionalized and hybrid nanomaterials as drug delivery systems through citing recent examples targeted at lung cancer treatment.

Metal–Organic Framework (MOF) through the Lens of Molecular Dynamics Simulation: Current Status and Future Perspective

As hybrid porous structures with outstanding properties, metal–organic frameworks (MOFs) have entered into a large variety of industrial applications in recent years. As a result of their specific structure, that includes metal ions and organic linkers, MOFs have remarkable and tunable properties, such as a high specific surface area, excellent storage capacity, and surface modification possibility, making them appropriate for many industries like sensors, pharmacies, water treatment, energy storage, and ion transportation. Although the volume of experimental research on the properties and performance of MOFs has multiplied over a short period of time, exploring these structures from a theoretical perspective such as via molecular dynamics simulation (MD) requires a more in-depth focus. The ability to identify and demonstrate molecular interactions between MOFs and host materials in which they are incorporates is of prime importance in developing next generations of these hybrid structures. Therefore, in the present article, we have presented a brief overview of the different MOFs’ properties and applications from the most recent MD-based studies and have provided a perspective on the future developments of MOFs from the MD viewpoint.

A Luminescent Mg-Metal-Organic Framework for Sustained Release of 5-Fluorouracil: Appropriate Host-Guest Interaction and Satisfied Acid-Base Resistance

It is important to achieve a moderate sustained release rate for drug delivery, so it is critical to regulate the host-guest interactions for the rational design of a carrier. In this work, a nano-sized biocompatible metal-organic framework (MOF), Mg(H₂TBAPy)(H₂O)₃·C₄H₈O₂ (TDL-Mg), was constructed by employing π-conjugated 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H₄TBAPy) as a ligand and used for 5-fluorouracil (5-FU) loading (28.2 wt %) and sustained slow release. TDL-Mg exhibits a 3D supramolecular architecture featuring a 1D rectangle channel with a size of 6.2 × 8.1 Ų and a Brunauer-Emmett-Teller surface area of 627 m²·g^-1. Channel microenvironment analysis shows that the rigid H₂TBAPy^2- ligand adopts special torsion to stabilize the channels and offer rich π-binding sites; the partially deprotonated carboxyls not only participate in the formation of strong hydrogen bonds but also create a mild pH buffer environment for biological applications. Suitable host-guest interactions are generated by the synergistic effect of polydirectional hydrogen bonds, multiple π-interactions, and confined channels, which allow 5-FU@TDL-Mg to release 76% of load in 72 h, a medically reasonable rate. Microcalorimetry was used to directly quantify these host-guest interactions with a moderate enthalpy of 22.3 kJ·mol^-1, which provides a distinctive thermodynamic interpretation for understanding the relationship between the MOF design and the drug release rate. Additionally, the nano-sized 5-FU@TDL-Mg can be taken up by mouse breast cancer cells (4T1 cells) for imaging based on the dramatic fluorescence change during the release of 5-FU, exhibiting potential applications in biological systems.