Polymer-Assisted 3D Printing of Inductor Cores.

Poly(glycerol monomethacrylate) (PGMA) prepared by reversible addition-fragmentation chain transfer polymerization was investigated as an additive for high-loading iron oxide nanoparticle (IOP) 3D printable inks. The effect of adjusting the molar mass and loading of PGMA on the rheology of IOP suspensions was investigated, and an optimized ink formulation containing 70% w/w IOPs and 0.25% w/w PGMA98 at pH 10 was developed. This ink was successfully 3D printed onto various substrates and into several structures, including rectangles, high aspect ratio cylinders, letters, spiral- and comb-shaped structures, and thin- and thick-walled toroids. The effect of sintering on the mechanical properties of printed artifacts was investigated via four-point flexural and compressive testing, with higher sintering temperatures resulting in improved mechanical properties due to changes in the particle size and microstructure. The printed toroids were fabricated into inductors, and their electrical performance was assessed via impedance spectroscopy at a working frequency range of 0.001-13 MHz. There was a clear trade-off between electrical properties and sintering temperature due to a phase change between γ-Fe2O3 and α-Fe2O3 upon heating. Nevertheless, the optimized devices had a Q factor of ∼40 at 10 MHz, representing a superior performance compared to that of other inductors with iron oxide cores previously reported. Thus, this report represents a significant step toward the development of low-cost, fully aqueous, high loading, and 3D printable ceramic inks for high-performance inductors and functional devices.

3D printable, thermo-responsive, self-healing, graphene oxide containing self-assembled hydrogels formed from block copolymer wormlike micelles.

Graphene oxide (GO) containing block copolymer nanocomposite hydrogels formed from poly(glycerol monomethacrylate-block-hydroxypropyl methacrylate) (PGMA-PHPMA) wormlike micelles were prepared by either mixing GO and copolymer at low temperature or via in situ reversible addition-fragmentation chain-transfer (RAFT) polymerisation-induced self-assembly (PISA) of HPMA in the presence of a PGMA macromolecular chain-transfer agent and GO flakes. Hydrogels containing 15-25% w/w copolymer and 0 and 8% w/w GO, based on copolymer, were investigated and the maximum gel strength measured was ∼33 kPa for a 25% w/w copolymer gel prepared by in situ polymerisation and containing 2% w/w GO based on copolymer. This gel strength represents a fifteen-fold increase over the same copolymer gel without the addition of GO. The nanocomposite gels were found to recover efficiently after the application of high shear, with up to 98% healing efficiency within seconds. These gels are also 3D printable, self-healing, adhesive and temperature responsive on cooling and re-heating. The observed properties were both GO and copolymer concentration dependent, and tensile testing demonstrated that the nanocomposite gels had higher moduli, elongation at break and toughness than gels prepared without GO.

A versatile and multifunctional metal-organic framework nanocomposite toward chemo-photodynamic therapy.

Previously most of the applications of targeting components have been based on the enhanced permeability and retention effect achieved using folic acid, which consider the side effects of the targeting components to some extent. Herein, we report a new strategy to decorate the surface of MOFs using a pemetrexed (MTA) targeting molecule, affording a new drug delivery system of ALA@UIO-66-NH-FAM/MTA (ALA = 5-amino-levulinic acid and FAM = 5-carboxyfluorescein). The confocal microscopy and flow cytometry results showed that ALA@UIO-66-NH-FAM/MTA presented a better targeting effect compared to ALA@UIO-66-NH-FAM/FA (FA = folic acid) and indicated a gradually increasing tendency of the targeting effect with the increasing expression of folate receptors on the tumor cell cytomembrane. Furthermore, the cytotoxicity experiment indicates that the combination of chemotherapy and photodynamic therapy is a more effective therapy model than single chemotherapy and photodynamic therapy. This work demonstrates the first attempt at folic acid antagonist (MTA) modification for NMOFs, providing a new concept for the design of MOFs with folate receptor targeting capacity for clinical applications.

Metal-Organic Framework (MOF)-based Nanomaterials for Biomedical Applications.

BACKGROUND: Metal-organic frameworks (MOFs), as a new class of porous organic-inorganic crystalline hybrid materials that governed by the self-assembled of metal atoms and organic struts have attracted tremendous attention because of their special properties. Recently, some more documents have reported different types of nanoscale metal-organic frameworks (NMOFs) as biodegradable and physiological pH-responsive systems for photothermal therapy and radiation therapy in the body. DISCUSSION: In this review paper aims at describing the benefits of using MOF nanoparticles in the field of biomedicine, and putting into perspective their properties in the context of the ones of other NPs. The first section briefly reviews the biomaterial scaffolds of MOFs. The second section presents the main types of stimuli-responsive mechanisms and strategies from two categories: intrinsic (pH, redox state) and extrinsic (temperature, light irradiation and magnetic field) ones. The combinations of photothermal therapy and radiation therapy have been concluded in detail. Finally, clinical applications of MOFs, future challenges and perspectives are also mentioned. CONCLUSION: This review outlines the most recent advances MOFs design and biomedical applications, from different synthesis to their use as smart drug delivery systems, bioimaging technology or a combination of both.

Hydrogen-Bonded Organic⁻Inorganic Hybrid Based on Hexachloroplatinate and Nitrogen Heterocyclic Cations: Their Synthesis, Characterization, Crystal Structures, and Antitumor Activities In Vitro.

Three new crystal structures containing [PtCl6]2−, pyridinium and benzimidazole groups have been prepared: [PtCl6]·(H-bzm)2·2(H2O) (1), [PtCl6]·(H-bipy)2·2(H2O) (2), [PtCl6]·(H-dimethyl-bipy)2·2(H2O) (3) [H-bzm: benzimidazole cation, H-bipy: 2,2'-bipyridine cation, H-dimethyl-bipy: 4,4'-bimethyl-2,2'-bipyridine cation]. All compounds have been fully characterized by elemental analyses, single-crystal X-ray analyses, IR spectra, TG analyses, and fluorescence studies. Single-crystal X-ray diffraction analysis suggests that the primary synthon contains ⁺N⁻H···Cl−, including ionic bonding and hydrogen bonding interactions. The dimensions are enhanced further by secondary O⁻H ∙∙Cl and N⁻H ∙∙O hydrogen bonding interactions between donor and acceptor atoms located at the periphery of these synthons. Moreover, coulombic attractions between the ions play an important role in reinforcing the structures of these complexes. In addition, antitumor activity against human lung adenocarcinoma cell line (A549) and human nasopharyngeal carcinoma cell line (CNE-2) was performed. These complexes all showed inhibition to the two cell lines, while complex 3 exhibited higher efficiency than complexes 1⁻2.

A 3D Stable Metal⁻Organic Framework for Highly Efficient Adsorption and Removal of Drug Contaminants from Water.

We herein selected a 3D metal⁻organic framework decorated with carboxylate groups as an adsorbent to remove the pharmaceutical molecules of diclofenac sodium and chlorpromazine hydrochloride from water. The experiment aimed at exploring the effect factors of initial concentration, equilibrium time, temperature, pH and adsorbent dosage on the adsorption process. The adsorption uptake rate of the diclofenac sodium is much higher than that of the chlorpromazine hydrochloride. This paper presents the high adsorption capacity of diclofenac sodium, in which porous MOFs are used for the removal of drug contaminants from water. According to linear fitting with adsorption isotherm equation and kinetic equations, diclofenac sodium conforms to the Langmuir model and pseudo-first-order kinetic equation, while chlorpromazine hydrochloride accords with the Temkin model and pseudo-second-order kinetic equation. The results of the study indicate that the title compound could be a promising hybrid material for removing diclofenac sodium and chlorpromazine hydrochloride from wastewater.

Microporous Metal-Organic Framework Based on Ligand-Truncation Strategy with High Performance for Gas Adsorption and Separation.

By using the ligand-truncation strategy, a microporous metal-organic framework (1) with high surface area was designedly synthesized. MOF 1 shows a new (4, 4)-connected net with a Schläfli symbol of (44.62)(43.62.8)2(42.82.102) and exhibits a high H2 capture capacity (193 cm3 g-1 at 1 atm and 77 K) and selectivities for CO2 over N2 and CH4 at low pressure.

[Comparation of constitutions between raw Psoralea corylifolia L. and processed one].

OBJECTIVE: To study the processing material foundation of Psoralea corylfolia L. and compare the content of psoralen, isopsoralen and microelement between raw Psoralea corylifolia L. and processed one. METHODS: The content of psoralen, isopsoralen and microelement were obtained by HPLC-gradient elution and ICP-AES. RESULTS: The content of psoralen, isopsoralen and microelement Mn, Ca, Mg, Fe, Zn were raising, but the change of that of microelement Cu was not obvious. CONCLUSION: The content of effective composition of Psoralea corylifolia L. is raised by Lei-Gong method and the biological activity is improved simultaneously.