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Magnesium (Mg) and its alloys have attracted attention as potential biodegradable materials in orthopedics due to their mechanical and physical properties, which are compatible with those of human bone. However, the effect of the mismatch between the rapid material degradation and fracture healing caused by the adverse effect of hydrogen (H2), which is generated during degradation, on surrounding bone tissue has severely restricted the application of Mg and its alloys. Thus, the development of new Mg alloys to achieve ideal degradation rates, H2 evolution and mechanical properties is necessary. Herein, a novel Mg–1Zn–1Sn-xSr (x = 0, 0.2, 0.4, and 0.6 wt%) quaternary alloy was developed, and the microstructure, mechanical properties, corrosion behavior and biocompatibility in vitro/vivo were investigated. The results demonstrated that a minor amount of strontium (Sr) (0.2 wt %) enhanced the corrosion resistance and mechanical properties of Mg–1Zn–1Sn alloy through grain refinement and second phase strengthening. Simultaneously, due to the high hydrogen overpotential of tin (Sn), the H2 release of the alloys was significantly reduced. Furthermore, Sr-containing Mg–1Zn–1Sn-based alloys significantly enhanced the viability, adhesion and spreading of MC3T3-E1 cells in vitro due to their unique biological activity and the ability to spontaneously form a network structure layer with micro/nanotopography. A low corrosion rate and improved biocompatibility were also maintained in a rat subcutaneous implantation model. However, excessive Sr (>0.2 wt %) led to a microgalvanic reaction and accelerated corrosion and H2 evolution. Considering the corrosion resistance, H2 evolution, mechanical properties and biocompatibility in vitro and in vivo, Mg–1Zn–1Sn-0.2Sr alloy has tremendous potential for clinical applications., Graphical abstract Image 1, Highlights • 0.2 wt. % Sr enhances the corrosion resistance, mechanical properties and inhibits H2 evolution of Mg-1Zn-1Sn-based alloy. • Sr-containing Mg-1Zn-1Sn-based alloys have better compatibility and biological activity in vitro. • Sr-containing Mg-1Zn-1Sn-based alloys can spontaneously form a network structure layer with micro/nano topography. • Mg-1Zn-1Sn-0.2Sr exhibits excellent corrosion resistance and extremely low H2 evolution in vivo.

Polymer electrolytes (PEs) have attracted tremendous research interest for their potential to offer improved safety and energy capacity in next-generation battery technologies. Among the different classes of PEs, single-ion conductors (SICs) are particularly interesting due to their high transference numbers. Nevertheless, a detailed understanding of how molecular structure impacts the properties of SIC-PEs is absent, limiting the ability to design improved materials. Here, we present the synthesis and characterization of a new class (seven examples provided) of polyanions featuring fluorinated aryl sulfonimide tagged (FAST) anions as side chains. These "polyFAST"salts are shown to outperform the widely used poly[(4-styrenesulfonyl) (trifluoromethanesulfonyl)imide] due to their strongly electron-withdrawing side chains and enhanced distance between anionic sites, providing higher electronic conductivities at all salt concentrations and in some cases superior electrochemical oxidative stability. Moreover, they provide a platform for discovery of fundamental relationships between macromolecular composition, as programmed through monomer structure, and SIC-PE bulk properties. Finally, we leverage the electron-deficient nature of polyFAST salts to demonstrate a new poly(solvate ionic liquid) (polySIL) concept that offers a promising pathway toward high-performance PEO-free SIC-PEs.

Supramolecular fluorescent materials have attracted considerable attention in recent years since they endow specific and unique properties to materials. Nevertheless, the utilization of photoresponsive characteristics to modulate their fluorescence emission behaviors and functions remain rarely explored. Here a facile fabrication strategy for producing dual-emissive materials based on supramolecular gels is proposed. A bi-acylhydrazone supramolecular gelator BD was designed and synthesized by a Schiff base reaction. Interestingly, the gelator BD could self-assemble into the stable supramolecular gel BDG with a strong aggregation-induced emission (AIE) in DMF–H2O binary solutions via π–π stacking interactions. On the one hand, the BDG could selectively identify Al3+ in the gel state. Upon addition of Al3+, AIE BDG showed an obvious blue-shift (85 nm, from yellow–green to sky-blue). On the other hand, artificial light-harvesting systems were successfully fabricated in a gel environment based on the supramolecular strategy. In these systems, efficient energy transfer occurs between the BD assembly and the loaded acceptors. For instance, the transition from yellow–green to red light could be accomplished in the BDG/SR 101 system. Based on these, the manipulation of bi-color fluorescence emission was realized by interaction with Al3+ and energy transfer.

An artificial light-harvesting system (ALHS) has been designed and constructed based on supramolecular organogels made of a simple hydrazide-functionalized benzimidazole derivative (HB), as well as the fluorescent dye rhodamine B (RhB). RhB acted as a good acceptor to realize the energy-transfer process with good efficiency based on a HB/RhB assembly, which showed considerable fluorescence resonance energy transfer (FRET) efficiency of 53% for the energy transfer process. Remarkably, the obtained system showed superior color conversion abilities, converting blue light into orange light. By properly tuning the donor to acceptor ratio, bright orange light emission was achieved with a high fluorescence quantum yield of 35.5%. This system exhibited promise for applications relating to visible-light photo-transformation.

Here, Deshpande et al. describe the production and purification of mouse ferroportin (Fpn), the only known mammalian iron efflux protein, and selective loop deletion constructs with enhanced thermal stability. Transport activity and hepcidin responsiveness of the constructs were assessed in Xenopus oocytes. The present work establishes a new protocol for the generation of stable Fpn protein in solution, constituting a platform for continued biophysical studies., Ferroportin (Fpn) is an essential mammalian iron transporter that is negatively regulated by the hormone hepcidin. Our current molecular understanding of Fpn‐mediated iron efflux and regulation is limited due to a lack of biochemical, biophysical and high‐resolution structural studies. A critical step towards understanding the transport mechanism of Fpn is to obtain sufficient quantities of pure and stable protein for downstream studies. As such, we detail here an expression and purification protocol for mouse Fpn yielding milligram quantities of pure protein. We have generated deletion constructs exhibiting enhanced thermal stability and which retained iron‐transport activity and hepcidin responsiveness, providing a platform for further biophysical studies of Fpn.

Ferric citrate is approved as an iron replacement product in patients with non-dialysis chronic kidney disease and iron deficiency anemia. Ferric citrate-delivered iron is enterally absorbed, but the specific mechanisms involved have not been evaluated, including the possibilities of conventional, transcellular ferroportin-mediated absorption and/or citrate-mediated paracellular absorption. Here, we first demonstrate the efficacy of ferric citrate in high hepcidin models, including Tmprss6 knockout mice (characterized by iron-refractory iron deficiency anemia) with and without adenine diet-induced chronic kidney disease. Next, to assess whether or not enteral ferric citrate absorption is dependent on ferroportin, we evaluated the effects of ferric citrate in a tamoxifen-inducible, enterocyte-specific ferroportin knockout murine model (Villin-Cre-ERT2, Fpnflox/flox). In this model, ferroportin deletion was efficient, as tamoxifen injection induced a 4000-fold decrease in duodenum ferroportin mRNA expression, with undetectable ferroportin protein on Western blot of duodenal enterocytes, resulting in a severe iron deficiency anemia phenotype. In ferroportin-deficient mice, three weeks of 1% ferric citrate dietary supplementation, a dose that prevented iron deficiency in control mice, did not improve iron status or rescue the iron deficiency anemia phenotype. We repeated the conditional ferroportin knockout experiment in the setting of uremia, using an adenine nephropathy model, where three weeks of 1% ferric citrate dietary supplementation again failed to improve iron status or rescue the iron deficiency anemia phenotype. Thus, our data suggest that enteral ferric citrate absorption is dependent on conventional enterocyte iron transport by ferroportin and that, in these models, significant paracellular absorption does not occur.

Molecular details often dictate the macroscopic properties of materials, yet due to their vastly different length scales, relationships between molecular structure and bulk properties can be difficult to predict a priori, requiring Edisonian optimizations and preventing rational design. Here, we introduce an easy-to-execute strategy based on linear free energy relationships (LFERs) that enables quantitative correlation and prediction of how molecular modifications, i.e., substituents, impact the ensemble properties of materials. First, we developed substituent parameters based on inexpensive, DFT-computed energetics of elementary pairwise interactions between a given substituent and other constant components of the material. These substituent parameters were then used as inputs to regression analyses of experimentally measured bulk properties, generating a predictive statistical model. We applied this approach to a widely studied class of electrolyte materials: oligo-ethylene glycol (OEG)–LiTFSI mixtures; the resulting model enables elucidation of fundamental physical principles that govern the properties of these electrolytes and also enables prediction of the properties of novel, improved OEG–LiTFSI-based electrolytes. The framework presented here for using context-specific substituent parameters will potentially enhance the throughput of screening new molecular designs for next-generation energy storage devices and other materials-oriented contexts where classical substituent parameters (e.g., Hammett parameters) may not be available or effective., Parameterizing organic substituents: Chemical structures are quantitatively connected to Li+ conductivity and viscosity in a statistical model that allows for prediction of new electrolyte materials.

Mixed halide perovskite is essential to construct highly efficient tandem solar cells, whereas halide segregation is a main issue hindering their device efficiency for this kind of perovskite materials. Herein, we modify the solvents for the mixed halide precursor solution to suppress halide segregation during fabrication process. An alternative solvent, N-Methyl pyrrolidone (NMP), is used to replace commonly used solvent, dimethyl sulfoxide (DMSO). It is shown that the halide segregation and the resultant carrier recombination are notably suppressed. The improvements brought by NMP may correlate with its moderate Lewis base property, which modifies the crystallization process of the mixed halide perovskite film. Consequently, the device performance is greatly improved by using NMP. The device efficiency is increased from less than 10% for DMSO solvent to approach 14% for NMP solvent. This work provides a facile way to improve the device efficiency, which also highlights on the importance of the solvents on halide segregation.

CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) are promising materials due to their excellent optoelectronic properties. This work shows a successful anion exchange reaction in CsPbBr3 nanowire (NW) systems with HCl gas resulting in a blue-green light-emitting CsPbBr3@CsPbBr3-x Cl x core-shell heterojunction. By adjusting the reaction time and the reaction temperature, the structure and light emission of the NWs can be adjusted. The core-shell heterojunction NCs are stably luminescent in 24 h. The rational mechanism of anion exchange in perovskite NCs is also investigated. The work highlights the feasibility of NWs heterogeneously prepared under the HC1 gas atmosphere, which provides a new strategy for studying the two- and multicolor luminescent perovskite NCs.

The utilization of mixed cations is beneficial for taking the advantages of cations and achieving highly efficient perovskite solar cells (PSCs). Herein, the precisely small incorporation of CH(NH2)2 (FA) cations in methyl ammonium lead iodide (MAPbI3) enables the formation of compact, smooth perovskite film with high crystallinity. Consequently, the short-circuit current and the fill factor of the PSCs based on FAxMA1-xPbI3 perovskite are greatly improved, leading to the enhanced device efficiency. The champion PSC based on FA0.1MA0.9PbI3 exhibits a remarkably high efficiency of 22.02%. Furthermore, the PSCs based on FA0.1MA0.9PbI3 perovskite also show improved device stability. This work provides a simple approach to fabricate high-quality perovskite films and high-performance PSCs with better stability.

Lead halide perovskite materials are popular in optoelectronic applications due to their excellent properties, while their instability is still a bottleneck for their potential application. In this work, sodium yttrium fluoride (NaYF4) and zinc oxide (ZnO) were used as capsules to protect CsPbBr3 nanocrystals, greatly enhancing the resistance of CsPbBr3 nanocrystals to water and polar solvents. Water-resistant and stable luminescent CsPbBr3@NaYF4 and CsPbBr3@ZnO nanocrystals were obtained by using a simple solution-phase method. These water-stable enhanced perovskite nanocrystals are suitable for long-term stable optoelectronic applications in the atmosphere.

Sequence-controlled supramolecular polymers offer new design paradigms for generating stimuli-responsive macromolecules with enhanced functionalities. The dynamic character of supramolecular links present challenges to sequence definition in extended supramolecular macromolecules, and design principles remain nascent. Here, we demonstrate the first example of using stoichiometry-control to specify the monomer sequence in a linear supramolecular polymer by synthesizing both a homopolymer and an alternating copolymer from the same glycol-substituted cyanostar macrocycle and phenylene-linked diphosphate monomers. A 2:1 stoichiometry between macrocycle and diphosphate produces a supramolecular homopolymer of general formula (A)n comprised of repeating units of cyanostar-stabilized phosphate-phosphate dimers. Using a 1:1 stoichiometry, an alternating (AB)n structure is produced with half the phosphate dimers now stabilized by the additional counter cations that emerge hierarchically after forming the stronger cyanostar-stabilized phosphate dimers. These new polymer materials and binding motifs are sufficient to bear normal and shear stress to promote significant and tunable adhesive properties. The homopolymer (A)n, consisting of cyanostar-stabilized anti-electrostatic linkages, shows adhesion strength comparable to commercial superglue formulations based on polycyanoacrylate but is thermally reversible. Unexpectedly, and despite including traditional ionic linkages, the alternating copolymer (AB)n shows weaker adhesion strength more similar to commercial white glue based on poly(vinyl acetate). Thus, the adhesion properties can be tuned over a wide range by simply controlling the stoichiometric ratio of monomers. This study offers new insight into supramolecular polymers composed of custom-designed anion and receptor monomers and demonstrates the utility of emerging functional materials based on anion-anion linkages.

High-voltage rechargeable lithium-metal batteries (LMBs) require electrolytes that are compatible with both the Li metal anode (LMA) and the metal-oxide cathode. Herein, by imitating the fluorosulfonyl imide group from a well-known LMA-compatible salt, lithium bis(fluorosulfonyl) imide (LiFSI), we come up with an organic solvent dimethylsulfamoyl fluoride (FSO2NC2H6), a fluorosulfonamide (FSA) with two methyl substituents, to develop a new “full fluorosulfonyl” (FFS) electrolyte. Remarkably, it enables a highly reversible LMA with an excellent initial coulombic efficiency (CE) ∼91%, and rapidly approaching 99% within only 10 cycles, with average CE outperforming the well-known LMA-compatible fluoroethylene carbonate (FEC)-based electrolyte. Furthermore, benefitting from its high anodic stability against the oxidative LiNi0.6Mn0.2Co0.2O2 (NMC622) and LiMn2O4 (LMO) surfaces, the Li‖NMC622 cell retains 89% of its original capacity after 200 cycles using a limited Li excess anode. This electrolyte design strategy opens a new avenue for exploring new medium-concentration organic electrolytes for 4 V class lithium-metal batteries (LMBs).

Interface modification is critical for improving the device performance of perovskite light-emitting diodes (PeLEDs) based on an all-inorganic halide perovskite, CsPbBr3. Here, we show that inserting a thin hydrophilic polymer interlayer at the perovskite/hole transport layer (HTL) interface leads to the energy level alignment at this interface and the improved film quality of the perovskite layer. As a result, the turn-on voltage of the PeLEDs is reduced and the current efficiency is notably improved. Furthermore, the device stability is greatly enhanced by the polymer interlayer. The underlying mechanisms for the improvements in the device performance by the polymer interlayer are explored using different techniques and by comparison of different polymers. This work sheds light on the function of the polymer interlayer in modifying the device efficiency and stability of the PeLEDs.

Based on a new designed acyl hydrazone gelator (G2), we developed a supramolecular organogel in glycol with two different hydrophobic fluorescent dyes, namely rhodamine B (RhB) and acridine red, as acceptors. Both the G2@gel-RhB and G2@gel-acridine red systems showed high levels of energy-transfer efficiency and high fluorescence quantum yields.

Solution processed blue phosphorescent organic devices based on mixed host system were fabricated in this paper. A set of blue phosphorescent organic light emitting diodes (PhOLEDs) utilizing two small molecular materials of 3,3-Di(9H-carbazol-9-yl) biphenyl (mCBP) and 4,4′,4′′-tris(N-carbazolyl)-triphenylamine (TCTA) as mixed host doped with phosphor bis[(4,6-difluorophenyl)-pyridina-to-N,C2](picolinate) iridium(III) (FIrpic) are fabricated. The results show that the performance of mixed host system devices is improved compared with two single host devices. The max luminance of 23,340 cd/m2 is achieved in the mCBP:TCTA (2:1) mixed host device while the 14,400 cd/m2 in mCBP single host devices and the 12,968 cd/m2 in TCTA, and the current efficiency is improved from 8.17 cd/A(mCBP), 9.61 cd/A (TCTA) to 13.62 cd/A at the luminance of 1000 cd/m2. The transient electroluminescence measurement was utilized to detect the carrier injection between two kinds of PhOLEDs and penetrate how the trap charges works in the mixed host devices. This presents that the mixed host system contributes to the hole injection and the equilibrium of the carrier transport, reduces trapped charges, thus brings about high efficiency devices.

We demonstrate solution-processed inverted polymer light-emitting diodes (PLEDs) using a yellow emitting copolymer “Super Yellow” (SY). The PLEDs exhibit high performance with a luminance above 17000 cd m−2 at 8 V and a maximum external quantum efficiency (EQE) of 4.1%, which is higher than its theoretical limit. We investigate the dynamic properties of polymeric excitons upon both photo- and electro-excitation. The results give an overview of the fundamental dynamic of monomolecular excitons, suggesting that the extra high EQE could be attributed to the generating of more than 25% prompt singlet excitons other than the bimolecular processes such as triplet-triplet annihilation(TTA). Furthermore, by extending the exciton formation zone and tuning the charge distribution inside the devices, dominated process in the exciton quenching, which is the main reason for the efficiency roll-off under high current density, is confirmed to be polaron-exciton quenching process.

BACKGROUND: Nano-hydroxyapatite/polyamide 66 (nHA/PA66) is a composite used widely in the repair of bone defects. However, this material is insufficient bioactivity. In contrast, D-RADA16-RGD self-assembling peptide (D-RADA16-RGD sequence containing all D-amino acids is Ac-RADARADARADARADARGDS-CONH(2)) shows admirable bioactivity for both cell culture and bone regeneration. Here, we describe the fabrication of a favorable biomaterial material (nHA/PA66/D-RADA16-RGD). METHODS: Proteinase K and circular dichroism spectroscopy were employed to test the stability and secondary structural properties of peptide D-RADA16-RGD respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the surface of these materials. Confocal laser scanning (CLS), cell counting kit-8 tests (CCK-8), alizarin red S staining, cell immunofluorescence analysis and Western blotting were involved in vitro. Also biosafety and bioactivity of them have been evaluated in vivo. RESULTS: Proteinase K and circular dichroism spectroscopy demonstrated that D-RADA16-RGD in nHA/PA66 was able to form stable-sheet secondary structure. SEM and TEM showed that the D-RADA16-RGD material was 7–33 nm in width and 130–600 nm in length, and the interwoven pore size ranged from 40 to 200 nm. CLS suggests that cells in nHA/PA66/D-RADA16-RGD group were linked to adjacent cells with more actin filaments. CCK-8 analysis showed that nHA/PA66/D-RADA16-RGD revealed good biocompatibility. The results of Alizarin-red S staining and Western blotting as well as vivo osteogenesis suggest nHA/PA66/D-RADA16-RGD exhibits better bioactivity. CONCLUSION: This study demonstrates that our nHA/PA66/D-RADA16-RGD composite exhibits reasonable mechanical properties, biocompatibility and bioactivity with promotion of bone formation. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13770-018-0171-5) contains supplementary material, which is available to authorized users.

A novel high concentration doping method based on the transformation from Cs4PbBr6 nanocrystals (NCs), which reacted with divalent metal bromide MBr2, to CsPbxM1−xBr3 NCs was developed. Two types of M2+ and Zn2+ which cannot emit light and Mn2+ and Eu2+ which can be used as the luminous centres, were chosen to trigger the transformation of Cs4PbBr6 NCs to CsPbxM1−xBr3 NCs. CsPbxZn1−xBr3 NCs maintained high photoluminescence quantum yields (PLQY) (>75%) and had good dispersion in hexane without obvious dissolution or agglomeration after two weeks. By adjusting the reaction temperature, the intrinsic band edge luminescence and the emission of Mn2+ ions CsPbxMn1−xBr3 NCs show different colours of light from green, green-yellow, pink, and orange-red to purple under an excitation of 365 nm. CsPbxEu1−xBr3 NCs were synthesized for the first time, and a weak luminescence around 618 nm from Eu3+ was detected in addition to the band edge luminescence of NCs. X-ray photoelectron spectroscopy (XPS) data showed that Zn2+, Mn2+ and Eu3+ (Eu2+) doping concentrations are up to 80%, 75% and 50%, respectively. We also analysed the doping mechanism and compared the new method with the traditional high temperature injection method. The lead-depleted perovskite NCs transformed from Cs4PbBr6 can provide a feasible pathway to reduce the lead toxicity of perovskite NCs and expand their applications.

International audience; The recognition of substituted phosphates underpins many processes including DNA binding, enantioselective catalysis, and recently template-directed rotaxane synthesis. Beyond ATP and a few commercial substrates, however, little is known about how substituents effect organophosphate recognition. Here, we examined alcohol substituents and their impact on recognition by cyanostar macrocycles. The organophosphates were disubstituted by alcohols of various chain lengths, dipropanol, dihexanol, and didecanol phosphate, each accessed using modular solid-phases syntheses. Based on the known size-selective binding of phosphates by π-stacked dimers of cyanostars, threaded [3]pseudorotaxanes were anticipated. While seen with butyl substituents, pseudorotaxane formation was disrupted by competitive OH···O– hydrogen bonding between both terminal hydroxyls and the anionic phosphate unit. Crystallography also showed formation of a backfolded propanol conformation resulting in an 8-membered ring and a perched cyanostar assembly. Motivated by established entropic penalties accompanying ring formation, we reinstated [3]pseudorotaxanes by extending the size of the substituent to hexanol and decanol. Chain entropy overcomes the enthalpically favored OH···O– contacts to favor random-coil conformations required for seamless, high-fidelity threading of dihexanol and didecanol phosphates inside cyanostars. These studies highlight how chain length and functional groups on phosphate’s substituents can be powerful design tools to regulate binding and control assembly formation during phosphate recognition.

Summary Fluorescence is critical to applications in optical materials including OLEDs and photonics. While fluorescent dyes are potential key components of these materials, electronic coupling between them in the solid state quenches their emission, preventing their reliable translation to applications. We report a universal solution to this long-standing problem with the discovery of a class of materials called small-molecule ionic isolation lattices (SMILES). SMILES perfectly transfer the optical properties of dyes to solids, are simple to make by mixing cationic dyes with anion-binding cyanostar macrocycles, and work with major classes of commercial dyes, including xanthenes, oxazines, styryls, cyanines, and trianguleniums. Dyes are decoupled spatially and electronically in the lattice by using cyanostar with its wide band gap. Toward applications, SMILES crystals have the highest known brightness per volume and solve concentration quenching to impart fluorescence to commercial polymers. SMILES materials enable predictable fluorophore crystallization to fulfill the promise of optical materials by design.

Amines are ubiquitous in the chemical industry and are present in a wide range of biological processes, motivating the development of amine-sensitive sensors. There are many turn-on amine sensors, however there are no examples of turn-on sensors that utilize the amine's ability to react by single electron transfer (SET). We investigated a new turn-on amine probe with a 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) fluorophore. BODIPY fluorescence is first preprogrammed into an off state by internal photoinduced electron transfer (PET) to an electron-deficient quinolinium ring, resulting in fluorescence quenching. At low concentrations of aliphatic amine (0 to 10 mM), this PET pathway is shut down by external SET from the amine to the photoexcited charge-transfer state of the probe and the fluorescence is turned on. At high concentrations of amine (50 mM to 1 M), we observed collisional quenching of the BODIPY fluorescence. The probe is selective for aliphatic amines over aromatic amines, and aliphatic thiols or alcohols. The three molecular processes modulate the BODIPY fluorescence in a multi-mechanistic way with two of them producing a direct response to amine concentrations. The totality of the three molecular processes produced the first example of a multi-state and dose-responsive amine sensor.

Yanan Xu,1 Hong Li,2 Jieming Wu,3 Qiming Yang,1 Dianming Jiang,4 Bo Qiao1 1Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China; 2Research Center for Nano-Biomaterials, Analytical and Testing Center, Sichuan University, Chengdu, People’s Republic of China; 3Office of Teaching Affairs, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China; 4Department of Orthopedics, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China Background: Hydroxyapatite/polyamide 66 (HA/P66) has been clinically used for several years owing to its good biocompatibility and bioactivity. However, it has been found that the osseointegration process of the HA/P66 implant takes a large amount of time because of the small amount of HA on its surface.Methods: To increase the amount of HA and aid faster osseointegration, we prepared a HA coating using a biomimetic process assisted by polydopamine (PDA) on the HA/P66 substrate. The surface properties of the substrate modified by PDA and HA were characterized, and the capacity of biomaterials for osteogenic induction was investigated both in vitro and in vivo. Results: The HA coating was successfully prepared on the HA/P66 substrate and verified by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The HA coating remained firmly attached to the underlying PDA-HA/P66 substrate even after strong ultrasound treatment for 1 h, and the calcium and phosphorus of the HA coating was continuously released in vitro in a slow manner. The formation of the HA coating on the PDA film greatly increased the hydrophilicity and surface roughness of HA/P66. In cell-based experiments, as compared with the HA/P66 substrate, the HA coating formation on the PDA film could facilitate the functions of C3H10T1/2 cells, including cell adhesion, proliferation, spreading, alkaline phosphatase activity, calcium nodule formation, and expression of osteogenic differentiation-related proteins. In addition, the HA/P66 scaffolds modified with PDA and HA coatings were implanted in rabbit femoral condyles. At 8 weeks after surgery, micro-computed tomography scanning (micro-CT) and hematoxylin–eosin (HE) staining revealed that more new bones were formed around the HA/P66 scaffold that was modified with a PDA-assisted HA coating. Conclusion: These results indicate that the preparation of a PDA-assisted HA coating by using a biomimetic process significantly improves the capacity of biomaterials for osteogenic induction. Keywords: hydroxyapatite, polydopamine, hydroxyapatite/polyamide 66, surface modification, osteogenic induction

A new near-infrared-responsive photocatalyst of NaYF4:Yb,Tm@Cu2O have been successfully synthesized by a simple method. Methylene blue as a model pollutant was used to study the photocatalytic activity of NaYF4:Yb,Tm@Cu2O composites, and the energy transfer process between NaYF4:Yb, Tm and Cu2O and the origin of the degradation of pollutants were investigated. It was found that the energy transfer route between NaYF4:Yb, Tm and Cu2O is an important factor for the overall photocatalytic activity. This study suggests a promising system to apply upconversion materials for utilizing the near-infrared light to irradiate Cu2O-based photocatalysts.

In polymer solar cells (PSCs) which are typically processed from solution, the molecules inside the active layer accumulate disorderly, which greatly hinders the exciton dissociation and carrier transport, especially in thick active layers. Here, we propose an effective and simple strategy to solve such problem in poly [(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di (2-octyldodecyl) 2,2’; 5′,2’’; 5″,2‴-quaterthiophen-5,5‴-diyl)] (PffBT4T-2OD) polymer based thick active layer by regulating the polymer crystallize behavior via incorporating two synergistic additives diphenylether (DPE) and 1-chloronaphthalene (CN) during the film processing. The as-prepared active layer enables the PSC exhibiting a remarkable high photoelectric conversion efficiency of 10.93%, which is much higher than the standard PSC fabricated without additives under the same conditions (9.05%) or with single additive. The high PCE of the PSCs is a result of the highly ordered molecular packing and the formation of three-dimensional charge transport channels of the polymer donor. It is evidenced that the microstructure of the active layer treated simultaneously with DPE and CN undergoes a double change in the orderly stacking of the alkyl chain and the π-π bond, which is more favorable for the charge transport. The results indicate that the active layer with two synergistic additives can be used as an effective and convenient method for controlling the film morphology in the polymer solar cells.

The power conversion efficiencies (PCEs) of potential polymer solar cells have been shown to rapidly exceed 15%. However, these high-performance devices are based on halogenated solvents that pose a significant hazard to the atmospheric environment and human beings. The use of nonhalogenated solvents makes the device less efficient because of its solubility issues. In this work, we report high-efficiency devices utilizing PffBT4T-2OD and [6,6]-phenyl C71 butyric acid methyl ester system from nonhalogenated solvents such as o-xylene (o-XY) and 1-methylnaphthalene (Me) hydrocarbon solvent. When Me was used as the additive, the PCE of prepared devices improved from 1.83 to 10.13%, which is rather higher than that of the devices processed with traditional solvents combined with chlorobenzene and 1,8-diiodooctane (8.18%). Both atomic force microscopy and transmission electron microscopy confirmed that after nonhalogen solvents are treated, a more finely phase-separated dense morphology of active layers than af...

Nonclassical ferroportin disease (FD) is a form of hereditary hemochromatosis caused by mutations in the iron transporter ferroportin (Fpn), resulting in parenchymal iron overload. Fpn is regulated by the hormone hepcidin, which induces Fpn endocytosis and cellular iron retention. We characterized 11 clinically relevant and 5 nonclinical Fpn mutations using stably transfected, inducible isogenic cell lines. All clinical mutants were functionally resistant to hepcidin as a consequence of either impaired hepcidin binding or impaired hepcidin-dependent ubiquitination despite intact hepcidin binding. Mapping the residues onto 2 computational models of the human Fpn structure indicated that (1) mutations that caused ubiquitination-resistance were positioned at helix-helix interfaces, likely preventing the hepcidin-induced conformational change, (2) hepcidin binding occurred within the central cavity of Fpn, (3) hepcidin interacted with up to 4 helices, and (4) hepcidin binding should occlude Fpn and interfere with iron export independently of endocytosis. We experimentally confirmed hepcidin-mediated occlusion of Fpn in the absence of endocytosis in multiple cellular systems: HEK293 cells expressing an endocytosis-defective Fpn mutant (K8R), Xenopus oocytes expressing wild-type or K8R Fpn, and mature human red blood cells. We conclude that nonclassical FD is caused by Fpn mutations that decrease hepcidin binding or hinder conformational changes required for ubiquitination and endocytosis of Fpn. The newly documented ability of hepcidin and its agonists to occlude iron transport may facilitate the development of broadly effective treatments for hereditary iron overload disorders.

The grain size of perovskite films is a key factor to optimize the performance of perovskite photovoltaic devices. Herein, a new route is developed in this paper to prepare CH3NH3PbI3 (MAPbI3) films with a better morphology and crystallization. This method includes the spin coating deposition of perovskite films with a precursor solution of PbI2 and CH3NH3I at the molar ratio 1 : 1 and thermal annealing (TA). The thermal annealing is conducted with a thermal-induced process to realize grain growth with solvent evaporation. In addition, a mixed solvent vapor treatment in acetic acid with chlorobenzene (HAc/CB) improves the morphology and crystallization of films further. As a result, the photovoltaic device based on the perovskite film treated by mixed HAc/CB solvent exhibits the best efficiency of 13.15% in comparison to the control device with 11.44% under AM 1.5G irradiation (100 mW cm−2).

The ternary solar cell has been proved as an elegant strategy to realize efficient bulk heterojunction (BHJ) organic solar cells (OSCs) by harvesting a larger range of photons than binary devices. In order to design such an efficient system, the charge carrier transport and recombination in ternary OPVs must be considered. We fabricated various ternary devices by adding squaraine derivatives (SQ-1, SQ-2, SQ-3, SQ-4 and SQ-5) with complementary absorption spectrum in near infrared region as the additional donor material into Poly [[9-(1-octylnonyl)-9H-carbazole-2, 7-diyl]-2, 5-thiophenediyl-2, 1, 3-benzothiadiazole-4, 7-diyl-2, 5-thiophenediyl] (PCDTBT): [6,6]-phenyl C71 butyric acid methyl ester (PC71BM) host binary blend film in this paper. Through the charge carrier mobility and transient photovoltage (TPV) measurements, it is found that the incorporation of 10% SQ-5 with shallower Highest Occupied Molecular Orbital (HOMO) level hinders holes in transferring from SQ to PCDTBT, which leads to unbalanced charge carrier transport, significant charge recombination, and decrease of performance. On the contrary, the performance of ternary devices incorporated with 10% SQ-3 with deeper HOMO energy level is improved by 21% compared with binary devices, which can be attributed to increased photon harvesting and changeless charge carrier characteristics.

Purpose : To investigate the therapeutic effect of glucosamine cyclohexyl ester on osteoarthritis (OA) in a rat model. Methods : Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot assays were used to analyze the effect of glucosamine cyclohexyl ester on changes in mRNA and protein expressions of matrix metalloproteinase and tissue inhibitor of metalloproteinases-1 in isolated rat chondrocytes, and in a rat model of OA. The rat model of OA was prepared by injecting monoiodoacetate to Sprague-Dawley rats via intra-articular route. Results : Treatment of the chondrocytes with glucosamine cyclohexyl ester for 48 h prevented interleukin-1 β (IL-1β)-mediated increases in mRNA and protein expressions in matrix metalloproteinases-1, -3 and -13, and also blocked IL-1β-induced decreases in mRNA and protein expressions of tissue inhibitor of metalloproteinase-1. Glucosamine cyclohexyl ester treatment also blocked the onset of morphological changes such as irregular surface, adhesion of tissues and presence of osteophytes in the femoral condyle surface of the OA rats. Mankin score for control, OA and glucosamine cyclohexyl ester treatment groups were 0.98 ± 0.15, 8.35 ± 0.88 and 2.39 ± 0. 67 (p = 0.002), respectively. Treatment of OA rats with glucosamine cyclohexyl ester also inhibited increases in the activities of matrix metalloproteinases-1, -3 and -13, and decreases of tissue inhibitor of metalloproteinase-1 mRNA and protein expressions. Treatment of chondrocytes and OA rats with IL-1β caused no significant changes in the levels of H3K27 and H4K8. Conclusion : These results show that glucosamine cyclohexyl ester prevents OA by targeting the expressions of matrix metalloproteinases-1, -3 and -13 and tissue inhibitor of metalloproteinases-1. Keywords : Metalloproteinases, Interleukin, Mankin score, Osteoarthritis, Cartilage

The acid-base switching of complexes formed from anti-electrostatic anion-anion homodimers of organophosphates and cyanostar macrocycles was investigated for the first time. High-fidelity 2:2 complexes were selected by using suitably sized organo substituents. Reversible and direct switching occurs with triflic acid and hydroxide base. An unexpected acid⋅⋅⋅anion heterodimer was discovered with weaker picric acid, which helped reveal some of the elementary steps. Switching can also proceed in a cooperative (strong anion then weak acid) or stepwise manner (weak acid then strong anion).

CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) are promising materials due to their excellent optoelectronic properties. In this work, we show a successful partial and reversible cation exchange reaction between Pb and Mn in both CsPbCl3 NCs and CsMnCl3 NCs systems to yield luminescent CsPb1–xMnxCl3 NCs. By adjusting the reaction time, the photoluminescence from the exciton emission of CsPbCl3 and the electron transition of Mn2+ can be tuned gradually. This work highlights the feasibility of a postsynthetic interconversion of Pb2+ and Mn2+ in cesium lead chloride perovskite nanocrystals, which enables a new strategy to reduce the toxicity and adjust the emissions of CsPbCl3 NCs. In the end, we also discuss the plausible mechanisms for cation exchange in perovskite materials.

Glioblastoma is the most aggressive primary brain tumor that originates from the glial cells in adults. Aberrant angiogenesis is essential for malignant glioblastoma tumorigenesis, development and metastasis. Lenvatinib is a multi‑targeted anticancer agent that targets of receptor tyrosine kinases including vascular endothelial growth factor receptor 1 and 2, fibroblast growth factor receptor 1, platelet‑derived growth factor receptor β and v‑kit Hardy‑Zuckerman 4 feline sarcoma viral oncogene homolog. In the present study, the therapeutic effects of lenvatinib as a treatment for glioblastoma were investigated in vivo and in vitro. The maximum dose toxicity (MDT) and treatment‑associated adverse events of lenvatinib were identified by cytotoxicity assay in experimental mice. Increasing levels of the pro‑apoptosis genes caspase‑3, -8, -9 and -10 following lenvatinib treatment were determined by reverse transcription‑quantitative polymerase chain reaction, and apoptosis of the malignant gliomas cells was analyzed by FACS. In vivo treatment with lenvatinib for BV‑2 bearing male BALC/c nude mice was assessed via tumor growth suppression and long‑term observation of survival. Subsequent cytotoxic T lymphocyte responses were further analyzed to determine the in vivo efficacy of lenvatinib treatment in mice with glioblastoma. The MDT of lenvatinib was identified as 0.24 mg, with relatively few side effects and improved efficacy in mice. Lenvatinib (0.24 mg) significantly increased apoptosis in BV‑2, C6, BC3H1 and G422 glioma cell lines. Tumor growth was significantly inhibited and tumor‑bearing mice demonstrated an improved survival rate following treatment with lenvatinib. In conclusion, lenvatinib provided an effective treatment outcome, and the results of the present study may help to achieve a comprehensive therapeutic schedule for clinical application.

Background: Galectin-3 (Gal-3) plays a role in the mechanisms underlying ocular venous malformation. We conducted this study to investigate the effect of pingyangmycin pretreatment on the Gal-3 expressions and biological behavior of ocular venous malformation. Methods: Tissue samples were collected from 136 patients with ocular venous malformation. Patients were randomly divided into pingyangmycin (n = 69) and nonpingyangmycin group (n = 67). Patients in the pingyangmycin group received a local injection of 0.02% pingyangmycin once every 2 days for 2 weeks (7 doses) before removal surgery, whereas patients in the nonpingyangmycin group underwent removal surgery without local injection. The protein and messenger RNA (mRNA) expression of Gal-3 were detected by using immunohistochemistry and in situ hybridization. Results: Gal-3 protein was expressed in 35 (52%) of 67 samples in the nonpingyangmycin group and in 19 (28%) of 69 samples in the pingyangmycin group (P < 0.05). Gal-3 mRNA expression was detected in 39 (58%) of 67 samples in the nonpingyangmycin group and 22 (32%) of 69 samples in the pingyangmycin group (P < 0.05). The higher Gal-3 expressions were detected in samples with deeper invasiveness than those with superficial invasiveness before (χ2 = 12.720 and 13.369, respectively, both P < 0.05) and after pingyangmycin treatment (χ2 = 8.429 and 4.590, respectively, both P < 0.05). It was more frequently detected in mesh-like lesions with unclear boundary than round lesions with clear boundary before (χ2 = 30.291 and 41.466, respectively, both P < 0.05) and after pingyangmycin treatment (χ2 = 14.619 and 15.130, respectively, both P < 0.05). Pingyangmycin treatment led to a significant difference in Gal-3 expressions at both protein and mRNA levels (χ2 = 8.664 and 9.524, respectively, both P < 0.05). Conclusions: Gal-3 expression may be involved in the development and invasiveness of ocular venous malformation, and pingyangmycin can inhibit Gal-3 expression, indicating a role of pingyangmycin treatment before the removal of ocular venous malformation. Key words: Galectin-3; Invasiveness; Pingyangmycin; Venous Malformation

Tetragonal rare-earth ions codoped LiScF 4 nanocrystals have been synthesized by a modified solvothermal method. The results revealed that the phase and morphology can be tailored through varying the synthesis conditions, such as reaction temperature and time. Meanwhile, the UC fluorescence emission spectra were measured. It turned out that the UC emission intensity can be significantly influenced by reaction temperature and time. Different from the NaYF 4 :20%Yb 3+ ,2%Er 3+ nanocrystals that usually emit green emission, yellow color emission can be observed in the LiScF 4 :20%Yb 3+ ,2%Er 3+ samples under 980 nm excitation, which illustrates that the obtained new phase LiScF 4 is suitable as a promising host for efficient UC fluorescence generation and tunable UC emission spectra. Moreover, the UC mechanism was investigated in detail.

Fluorescence is critical to many advanced materials including OLEDs and bioimaging. While molecular fluorophores that show bright emission in solution are potential sources of these materials, their emission is frequently lost in the solid state preventing their direct translation to optical applications. Unpredictable packing and coupling of dyes leads to uncontrolled spectral shifts and quenched emission. No universal solution has been found since Perkin made the first synthetic dye 150 years ago. We report the serendipitous discovery of a new type of material that we call small-molecule ionic isolation lattices(SMILES) tackling this long-standing problem. SMILES are easily prepared by adding two equivalents of the anion receptor cyanostar to cationic dyes binding the counter anions and inducing alternating packing of dyes and cyanostar-anion complexes. SMILES materials reinstate solution-like spectral properties and bright fluorescence to thin films and crystals. These positive outcomes derive from the cyanostar. Its wide 3.45-eV band gap allows the HOMO and LUMO levels of the dye to nest inside those of the complex as verified by electrochemistry. This feature simultaneously enables spatial and electronic isolation to decouple the fluorophores from each other and from the cyanostar-anion lattice. Representative dyes from major families of fluorophores, viz, xanthenes, oxazines, styryls, cyanines, and trianguleniums, all crystalize in the characteristic structure and regain their attractive fluorescence. SMILES crystals of rhodamine and cyanine display unsurpassed brightness per volume pointing to uses in demanding applications such as bioimaging. SMILES materials enable predictable fluorophore crystallization to fulfil the promise of optical materials by design.

Acrylamide (ACR), a neurotoxicity and carcinogenic chemical, has attracted considerable attention since it is present at high concentrations in thermally cooked carbohydrate-rich foods. ACR exposure significantly increased rate of fetal resorption, and decreased fetal body weights in mice. However, no detailed information is available about the effect of ACR on uterine decidualization, which is a vital process in the establishment of successful pregnancy. Thus, our aim of this study was to explore the effect and mechanism of ACR on uterine decidualization in vivo during mice pregnancy. Mice were gavaged with 0, 10, and 50 mg ACR /kg/day from gestational days (GD) 1 until GD 8, whereas pseudopregnant mice from pseudopregnant day (PPD) 4 until PPD 8. Results indicated ACR treatment dramatically reduced numbers of implanted embryos, and decreased the weights of implantation site and oil-induced uterus. Nevertheless, no significant difference was observed in the weights of no oil-induced uterus between control and ACR-treated group. Furthermore, ACR significantly reduced numbers of polyploidy and PCNA-positive decidual cells and expression of cyclin D3 and p21 proteins, and induced apoptosis of decidua, as presented by up-regulation of Bax and cleaved-caspase-3, and decreased Bcl-2 protein during normal pregnant and pseudopregnant process. In summary, ACR exposure significantly inhibited uterine endometrial decidualization via the apoptosis and suppression of cyclin D3/p21 in mice.

In inverted perovskite solar cells (PSCs), high-quality perovskite film grown on hole-transporting material (HTM) with pinhole-free coverage and a large grain size is crucial for high efficiency. Here, we report on the growth of pinhole-free and large grain CH3NH3PbI3 crystals favored by a hydrophobic small molecular HTM, namely, 4,4&rsquo, Bis(4-(di-p-toyl)aminostyryl)biphenyl (TPASBP). The hydrophobic surface induced by TPASBP suppressed the density of the perovskite nuclei and heterogeneous nucleation, thus promoting the perovskite to grow into a dense and homogeneous film with a large grain size. The CH3NH3PbI3 deposited on the TPASBP exhibited better crystallization and a lower trap density than that on the hydrophilic surface of indium tin oxide (ITO), resulting in a significant reduction in carrier recombination. Combined with the efficient hole extraction ability of TPASBP, a high efficiency of 18.72% in the inverted PSCs fabricated on TPASBP was achieved.

Background/aimPatients with polycystic ovary syndrome (PCOS), characterized by anovulation, hyperandrogenemia and polycystic ovaries, are still vulnerable to undergo recurrent pregnancy loss and premature labor even though the ovulatory process is pharmacologically recovered. However, its potential mechanism remains unknown. Thus, our aim was to investigate the effect and mechanism of hyperandrogenemia and flutamide (a non-steroidal anti-androgen) on the embryo implantation and pregnancy during mid-pregnancy.MethodsWe used a mouse model in which PCOS-like hyperandrogenemia was induced by subcutaneous injection of testosterone propionate. In this model, we observed the effect of hyperandrogenemia and flutamide on the decidualization, angiogenesis and uNK cells by methods of immunohistochemistry, quantitative PCR, western blotting and Dolichos biflorus agglutinin (DBA) lectin staining.ResultsTestosterone and flutamide treatment did not significantly influence the numbers of implanted embryo compared with the control group. However, different doses of testosterone significantly increased the ratio of resorbed /implanted embryo, decreased the level of prl8a2 mRNA and cyclin D3 protein, inhibited the uterine angiogenesis and reduced the numbers of uNK cells, but combined treatment with flutamide markedly decreased the resorbed embryos, increased expressions of prl8a2 mRNA and cyclin D3 protein and angiogenesis and numbers of uNK cells.ConclusionFlutamide treatment can efficiently ameliorate the hyperandrogenemia-induced the disorders in aspects of decidualization, angiogenesis and uNK cells, which further improve the poor endometrial receptivity in PCOS patients.

In this chapter, the synthesis and preparation of upconverting phosphor particles will be introduced. The components of rare earth upconversion luminescence materials are the activator, the sensitizer, and the host. There are many kinds of upconversion luminescence materials that have been discovered so far. Although they are mainly related compounds of rare earth elements, they can be classified into vanadates, phosphates, sulfides, sulfur oxides, oxides, oxyhalides, molybdates, etc. At present, the synthesis of high-quality rare earth halide upconversion luminescence nanomaterials mainly includes precipitation method, water/solvothermal method, pyrolysis method and sol-gel method. In order to apply UCNPs biologically, the hydrophilic modification of the surface, such as addition of carboxyl, amino or aldehyde groups, is very important and necessary. At the end, the main challenges of rare earth upconversion luminescence materials will be discussed.

Electrolytes with improved thermal and oxidative stability must be developed to achieve greater power and energy densities without compromising safety in modern energy storage devices. Because of their much-reduced solvent vapor pressure and expanded electrochemical windows, solvate ionic liquids (SILs) of lithium salts have recently attracted significant attention in this regard. The current palette of SILs is, however, limited to only a few suitable anions with limited chemical functionality. Guided by fundamental physical organic chemistry principles, we designed a new family of S-substituted fluorinated aryl sulfonamide-tagged anions that feature variable numbers of electronically neutral or withdrawing sulfide, sulfoxide, and sulfone substituents. Several salts of these electron deficient anions display very high electrochemical oxidative stability, good solubility, and a weakly coordinating nature that enables the synthesis of Li-based SILs with high thermal and electrochemical oxidative stability. This new family of functional, noncoordinating anions will potentially expand the scope of applications of SILs as safe electrolytes in battery devices.

We developed a colloidal synthesis of CsPbBr3 perovskite nanocrystals (NCs) at a relative low temperature (90 °C) for the bright blue emission which differs from the original green emission (∼510 nm) of CsPbBr3 nanocubes as reported previously. Shapes of the obtained CsPbBr3 NCs can be systematically engineered into single and lamellar-structured 0D quantum dots, as well as face-to-face stacking 2D nanoplatelets and flat-lying 2D nanosheets via tuning the amounts of oleic acid (OA) and oleylamine (OM). They exhibit sharp excitonic PL emissions at 453, 472, 449, and 452 nm, respectively. The large blue shift relative to the emission of CsPbBr3 bulk crystal can be ascribed to the strong quantum confinement effects of these various nanoshapes. PL decay lifetimes are measured, ranging from several to tens of nanoseconds, which infers the higher ratio of exciton radiative recombination to the nonradiative trappers in the obtained CsPbBr3 NCs. These shape-controlled CsPbBr3 perovskite NCs with the bright blue e...

To obtain higher device performance, the ideal bulk heterojunction (BHJ) morphology should feature both nanophase separation to increase charge generation and bi-continuous percolating networks to increase charge transport. In this paper, solvent additive, 1,8-diiodooctane (DIO), was used in PTB7-Th:PC71BM blend to improve BHJ morphology. The effect of DIO on charge generation and charge transport were studied carefully. Experimental study indicated that the effect of DIO on charge generation and charge transport are conflicted. Positive effects of DIO, which were induced by nanophase separation for charge generation in BHJ, are proved by the results of internal quantum efficiency (IQE) and photocurrent density (Jph), and negative effects of DIO on charge transport has been investigated according to the time-of-flight secondary ion mass spectrometer (TOF-SIMS).