Magnetic UiO-66-NH₂ Core–Shell Nanohybrid as a Promising Carrier for Quercetin Targeted Delivery toward Human Breast Cancer Cells

In this study, a magnetic core–shell metal–organic framework (MOF) nanocomposite, Fe3O4-COOH@UiO-66-NH2, was synthesized for tumor-targeting drug delivery by incorporating carboxylate groups as functional groups onto ferrite nanoparticle surfaces, followed by fabrication of the UiO-66-NH2 shell using a facile self-assembly approach. The anticancer drug quercetin (QU) was loaded into the magnetic core–shell nanoparticles. The synthesized magnetic nanoparticles were comprehensively evaluated through multiple techniques, including FT-IR, PXRD, FE-SEM, TEM, EDX, BET, UV–vis, ZP, and VSM. Drug release investigations were conducted to investigate the release behavior of QU from the nanocomposite at two different pH values (7.4 and 5.4). The results revealed that QU@Fe3O4-COOH@UiO-66-NH2 exhibited a high loading capacity of 43.1% and pH-dependent release behavior, maintaining sustained release characteristics over a prolonged duration of 11 days. Furthermore, cytotoxicity assays using the human breast cancer cell line MDA-MB-231 and the normal cell line HEK-293 were performed to evaluate the cytotoxic effects of QU, UiO-66-NH2, Fe3O4-COOH, Fe3O4-COOH@UiO-66-NH2, and QU@Fe3O4-COOH@UiO-66-NH2. Treatment with QU@Fe3O4-COOH@UiO-66-NH2 substantially reduced the cell viability in cancerous MDA-MB-231 cells. Cellular uptake and cell death mechanisms were further investigated, demonstrating the internalization of QU@Fe3O4-COOH@UiO-66-NH2 by cancer cells and the induction of cancer cell death through the apoptosis pathway. These findings highlight the considerable potential of Fe3O4-COOH@UiO-66-NH2 as a targeted nanocarrier for the delivery of anticancer drugs

Solid-State Structural Transformations of Two Ag^I Supramolecular Polymorphs to Another Polymer upon Absorption of HNO₃ Vapors

Solid-state structural transformation of two polymorphic forms of [Ag­(8-HqH)­(8-Hq)]n (1α and 1β, where 8-HqH = 8-hydroxyquinoline and 8-Hq– = 8-hydroxyquinolate) to {[Ag­(8-HqH)2]­NO3}n (2) has been observed upon solid–gas reaction of compounds 1α and 1β with HNO3 vapors. Solid–gas reaction of compound 2 with hydrated vapors of NH3 results in the formation of only the 1β polymorph, while solid–solid reaction of compound 2 with KOH results in the formation of a 1α and 1β mixture with chiral and achiral space groups of P212121 and Pbcn, respectively

Heterostructured Ag@MOF-801/MIL-88A(Fe) Nanocomposite as a Biocompatible Photocatalyst for Degradation of Reactive Black 5 under Visible Light

Heterostructured Ag@MOF-801/MIL-88A(Fe) nanocomposite was synthesized through template effects in metal–organic frameworks (MOFs). MIL-88A(Fe) was fabricated on a MOF-801 template using the internal extended growth method (IEGM) via polyvinylpyrrolidone (PVP) as the structure-director agent to create the MIL-88A(Fe)-on-MOF-801 heterostructure. The MOF-801/MIL-88A(Fe) heterostructure was used as a template for the formation of Ag nanoparticles (NPs) inside it via a double solvents method (DSM) combined with a photoreduction route (PR). To characterize synthesized samples to a high level of detail, PXRD, FT-IR, EDX, N2 adsorption–desorption isotherms, TEM, DRS, PL, EIS, and Mott–Sckottky measurements were used. The resulting Ag@MOF-801/MIL-88A(Fe) nanocomposite demonstrated the highest photocatalytic activity of 91.72% for the degradation of Reactive Black 5, after 30 min under visible light irradiation

Synthesis and Application of MOF-808 Decorated with Folic Acid-Conjugated Chitosan as a Strong Nanocarrier for the Targeted Drug Delivery of Quercetin

Herein, MOF-808 (MOF = metal–organic framework) based on zirconium tricarboxylate was synthesized to investigate the influence of decorating groups of folic acid-conjugated chitosan (CS-FA) on drug-delivery efficiency. Quercetin (QU) was loaded on nondecorated MOF-808 and then decorated with a folic acid–chitosan conjugate. The properties and activities of modified MOF-808 were compared with unmodified MOF-808. QU@MOF-808@CS-FA exhibited favorable drug-release properties, high drug-loading capacity, efficient targeting capability, and pH-dependent release behavior, highlighting the critical role of organic modification. A variety of characterization techniques were used to characterize MOF nanoparticles, including Fourier transform infrared, powder X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray, transmission electron microscopy, Brunauer–Emmett–Teller, ζ potential, and 1H NMR. Additionally, Monte Carlo simulation calculations were carried out to examine the interactions between the structures of MOF-808 and QU. An in vitro cytotoxicity test was conducted, and the results identified that QU@MOF-808@CS-FA demonstrated more superior therapeutics than QU@MOF-808 on FR-positive MCF7 cancerous cells. On the basis of the results, QU@MOF-808@CS-FA is a promising drug carrier by selective targeting and sustained release

Smart Multifunctional UiO-66 Metal–Organic Framework Nanoparticles with Outstanding Drug-Loading/Release Potential for the Targeted Delivery of Quercetin

Herein, UiO-66 and its two functional analogs (with −NO2 and −NH2 functional groups) were synthesized, and their potential ability as pH stimulus nanocarriers of quercetin (QU), an anticancer agent, was studied. UiO-66 is a low-toxicity, biocompatible metal–organic framework with a large surface area and good stability, which can be prepared through a facile and inexpensive method. Before and after drug loading, various analyses were conducted to characterize the synthesized nanocarriers. Moreover, Monte Carlo simulations were performed to investigate their structures and interactions with quercetin. The most promising drug loading potential and prolonged drug release (over 25 days) were observed in QU@UiO-66-NO2 with 37% drug loading content, which was the best-tested sample that exhibited a higher release rate under acidic conditions (pH = 5) than that in normal cells (pH = 7.4). This behavior is known as pH-stimulus-controlled ability. The cell treatment with free QU, UiO-66-R, and QU@UiO-66-R (R = −H, −NO2, and −NH2) was performed, and an MTT assay was conducted on HEK-293 and MDA-MB-231 cells for the cytotoxicity study. Additionally, the kinetic modeling of drug release was investigated on the basis of the analysis of the drug release profiles

MOF-801 as a Nanoporous Water-Based Carrier System for In Situ Encapsulation and Sustained Release of 5‑FU for Effective Cancer Therapy

Nanoporous metal–organic frameworks (MOFs) have been gaining a reputation for their drug delivery applications. In the current work, MOF-801 was successfully prepared by a facile, cost-efficient, and environmentally friendly approach through the reaction of ZrCl4 and fumaric acid as organic linkers to deliver 5-fluorouracil (5-FU). The prepared nanostructure was fully characterized by a series of analytical techniques including Fourier transform infrared spectroscopy, powder X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, UV–vis spectroscopy, 1H NMR spectroscopy, thermogravimetric analysis, high-performance liquid chromatography, and Brunauer–Emmett–Teller analysis. MOF-801 could be used for the delivery of the anticancer drug 5-FU due to its high surface area, suitable pore size, and biocompatible ingredients. Based on in vitro loading and release studies, a high 5-FU loading capacity and pH-dependent drug release behavior were observed. Moreover, the interactions between the structure of MOFs and 5-FU were investigated through Monte Carlo simulation calculations. An in vitro cytotoxicity test was done, and the results indicated that 5-FU@MOF-801 was more potent than 5-FU on SW480 cancerous cells, indicating the highlighted role of this drug delivery system. Finally, the kinetics of drug release was investigated

One-Dimensional Corrugated Tape Ag^I Coordination Polymers Constructed of Ag−C Bonds

Three one-dimensional (1D) polymers assembled of Ag−C bonds, [Ag2(μ3-L)2(MeCN)]n (1−3) [L = 4,4,4-trifluoro-1-phenyl-1,3-butandione (HTFPB) (1), 4,4,4-trifluoro-1-naphthyl-1,3-butandionate (HTFNB) (2), and 4,4,4-trifluoro-1-thiophen-1,3-butandione (HTFTB) (3)] have been synthesized and characterized by elemental analysis, IR, and 1H NMR spectroscopy. The thermal stability of compounds 1−3 were studied by thermal gravimetric and differential thermal analyses. The single-crystal X-ray structures of compounds 1 and 2 show two types of AgI ions with coordination numbers of five and four. The Ag atoms contain strong AgI−Cmethine bonds and thus produce 1D corrugated tape coordination polymers. Furthermore, the ligands and complexes 1−3 are luminescent in the solid state with emission maxima in the visible light region (λmax = 470 nm). The results of studies the stoichiometry and formation of complexes 1−3 in acetonitrile solution were found to be in support of their solid-state stoichiometries

Solid-State Structural Transformations of Two Ag^I Supramolecular Polymorphs to Another Polymer upon Absorption of HNO₃ Vapors

Solid-state structural transformation of two polymorphic forms of [Ag­(8-HqH)­(8-Hq)]_<i>n</i> (<b>1α</b> and <b>1β</b>, where 8-HqH = 8-hydroxyquinoline and 8-Hq^– = 8-hydroxyquinolate) to {[Ag­(8-HqH)₂]­NO₃}_<i>n</i> (<b>2</b>) has been observed upon solid–gas reaction of compounds <b>1α</b> and <b>1β</b> with HNO₃ vapors. Solid–gas reaction of compound <b>2</b> with hydrated vapors of NH₃ results in the formation of only the <b>1β</b> polymorph, while solid–solid reaction of compound <b>2</b> with KOH results in the formation of a <b>1α</b> and <b>1β</b> mixture with chiral and achiral space groups of <i>P</i>2₁2₁2₁ and <i>Pbcn</i>, respectively

One-Dimensional Corrugated Tape Ag^I Coordination Polymers Constructed of Ag−C Bonds

Three one-dimensional (1D) polymers assembled of Ag−C bonds, [Ag2(μ3-L)2(MeCN)]n (1−3) [L = 4,4,4-trifluoro-1-phenyl-1,3-butandione (HTFPB) (1), 4,4,4-trifluoro-1-naphthyl-1,3-butandionate (HTFNB) (2), and 4,4,4-trifluoro-1-thiophen-1,3-butandione (HTFTB) (3)] have been synthesized and characterized by elemental analysis, IR, and 1H NMR spectroscopy. The thermal stability of compounds 1−3 were studied by thermal gravimetric and differential thermal analyses. The single-crystal X-ray structures of compounds 1 and 2 show two types of AgI ions with coordination numbers of five and four. The Ag atoms contain strong AgI−Cmethine bonds and thus produce 1D corrugated tape coordination polymers. Furthermore, the ligands and complexes 1−3 are luminescent in the solid state with emission maxima in the visible light region (λmax = 470 nm). The results of studies the stoichiometry and formation of complexes 1−3 in acetonitrile solution were found to be in support of their solid-state stoichiometries