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In this study, the first magnetite nanoparticles (Fe3O4), and MIL-100(Fe) nanocatalyst via in situ two-step hydrothermal strategies were synthesized in which Fe3O4 is known as the magnetic core. MI...

The relatively new class of porous material known as metal-organic framework (MOF) exhibits unique features such as high specific surface area, controlled porosity and high chemical stability. Many green synthesis approaches for MOFs have been proposed using biocompatible metal ions and linkers to maximise their use in pharmaceutical fields. The involvement of biomolecules as an organic ligand can act promising because of their biocompatibility. Recently, cyclodextrin metal-organic frameworks (CD-MOFs) represent environmentally friendly and biocompatible characteristics that lead them to biomedical applications. They are regarded as a promising nanocarrier for drug delivery, due to their high specific surface area, high porosity, tuneable chemical structure, and easy fabrication. This review focuses on the unique properties of CD-MOF and the recent advances in methods for the synthesis of these porous structures with emphasis on particle size. Then, the state-of-the-art drug delivery systems with various drugs along with the performance of CD-MOFs as efficient drug delivery systems are presented. Particular emphasis is laid on researches investigating the drug delivery potential of ?-CD-MOF.

We present a rapid and surfactant-free temperature-assisted synthesis route to prepare γ-cyclodextrin-based metal–organic framework (γ-CD-MOF). The cubic crystals of the CD-MOF with an average edge length of 10–15 µm, specific surface area of 775 m2 g−1 and total pore volume of 0.229 cm3 g−1 were synthesized in much shorter time than conventional CD-MOFs. To show the efficiency of the synthesized CD-MOF as adsorbent of gas, the uptake of CO2 at different temperature and pressure was investigated. It is shown that the CO2 uptake increases with increasing pressure and decreasing temperature. Further microgravimetric investigation on gas adsorption at low pressure demonstrated superior gas uptake (ca. 147 mg g−1) than previous reports. At the maximum equilibrium pressure, the uptake amounts of CO2 were found to be 326 and 268 mg g−1 at 303 and 323 K, respectively. The synthesized CD-MOF has great potential to be used in gas storage and separation applications.

Environment-friendly nanosponges, having a high content of carboxyl groups, were synthesized by crosslinking &beta, cyclodextrin and linecaps, a highly soluble pea starch derivative, with citric acid in water. Additionally, pyromellitic nanosponges were prepared by reacting &beta, cyclodextrin and linecaps with pyromellitic dianhydride in dimethyl sulfoxide and used in comparison with the citric nanosponges. After ion-exchange of the carboxyl groups H+ with sodium ions, the ability of the nanosponges to sequester heavy metal cations was investigated. At a metal concentration of 500 ppm, the pyromellitate nanosponges exhibited a higher retention capacity than the citrate nanosponges. At lower metal concentrations (&le, 50 ppm) both the citrate and the pyromellitate nanosponges showed high retention capacities (up to 94% of the total amount of metal), while, in the presence of interfering sea water salts, the citrate nanosponges were able to selectively adsorb a significantly higher amount of heavy metals than the pyromellitate nanosponges, almost double in the case of Cu2+.

A new magnetic nanocomposite called MIL-100(Fe) @Fe3O4@AC was synthesized by the hydrothermal method as a stable adsorbent for the removal of Rhodamine B (RhB) dye from aqueous medium. In this work, in order to increase the carbon uptake capacity, magnetic carbon was first synthesized and then the Fe3O4 was used as the iron (III) supplier to synthesize MIL-100(Fe). The size of these nanocomposite is about 30&ndash, 50 nm. Compared with activated charcoal (AC) and magnetic activated charcoal (Fe3O4@AC) nanoparticles, the surface area of MIL-100(Fe) @Fe3O4@AC were eminently increased while the magnetic property of this adsorbent was decreased. The surface area of AC, Fe3O4@AC, and MIL-100(Fe) @Fe3O4@AC was 121, 351, and 620 m2/g, respectively. The magnetic and thermal property, chemical structure, and morphology of the MIL-100(Fe) @Fe3O4@AC were considered by vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunner-Emmet-Teller (BET), and transmission electron microscopy (TEM) analyses. The relatively high adsorption capacity was obtained at about 769.23 mg/g compared to other adsorbents to eliminate RhB dye from the aqueous solution within 40 min. Studies of adsorption kinetics and isotherms showed that RhB adsorption conformed the Langmuir isotherm model and the pseudo second-order kinetic model. Thermodynamic amounts depicted that the RhB adsorption was spontaneous and exothermic process. In addition, the obtained nanocomposite exhibited good reusability after several cycles. All experimental results showed that MIL-100(Fe) @Fe3O4@AC could be a prospective sorbent for the treatment of dye wastewater.

A magnetic metal-organic framework (MOF) composite, MIL-101(Fe)@PDopa@Fe3O4, was synthesized as the stable adsorbent for removal of methyl red (MR) and malachite green (MG) from wastewaters. A very thin film of 3,4-dihydroxy-L-phenylalanine (L-Dopa) was used as an efficient and environmentally friendly binder between Fe3O4 particles and MIL-101(Fe). Characterization of MIL-101(Fe)@PDopa@Fe3O4 was accomplished by various spectroscopic, microscopic and thermal analysis techniques. Magnetic properties of the composite were studied by vibrating sample magnetometer (VSM). Influencing factors such as pH, ionic strength, contact time, adsorbent dosage, temperature, and initial dye concentration on the adsorption ability of the MIL-101(Fe)@PDopa@Fe3O4 were investigated. The very excellent adsorption capacities (833.33 and 1250 mg/g for MG and MR, respectively) were achieved. Adsorption kinetics, thermodynamics and isotherms studies indicated that MG and MR adsorption followed Langmuir isotherm model and pseudo second-order kinetic model. The Adsorbent was successfully used to remove industrial colors from real textile wastewater. The MIL-101(Fe)@ PDopa@Fe3O4 was found to be recyclable for removal of MR and MG.