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Dicopper(ii) metal–organic frameworks constructed from fluorinated ligands exhibit ultra-high propyne storage under ambient conditions, which results from the suitable pore space and strong propyne⋯propyne interactions.

Here, a hexanuclear Co

Astrocytes are intimately linked with brain vessels, a relationship that is critical for neuronal health and function. However, astroglial factors driving these physical and functional associations during postnatal brain development have yet to be identified. We characterized structural and transcriptional changes in mouse cortical astrocytes and microvessels during the first two postnatal weeks and found that high-mobility group box 1 (Hmgb1), normally upregulated with injury and involved in adult cerebrovascular repair, was highly expressed in astrocytes at birth and then decreased rapidly. Astrocyte-selective ablation ofHmgb1at birth affected astrocyte morphology and endfoot placement, altered distribution of endfoot proteins connexin43 and aquaporin-4, induced transcriptional changes in astrocytes related to cytoskeleton remodeling, and profoundly disrupted endothelial ultrastructure. While lack of astroglialHmgb1did not affect the blood-brain barrier or angiogenesis postnatally, it impaired neurovascular coupling and behavior in adult mice. These findings identify astroglialHmgb1as a key player in postnatal gliovascular maturation.

Herein, a MOF with cavities decorated with high-density electronegative F and O sites for the challenging separation of a ternary equimolar mixture of C2H2, C2H4, and CO2 is presented.

Francisella tularensis subspecies tularensis (Ftt) is extremely virulent for humans when inhaled as a small particle aerosol (Ftt became a primary candidate for biological weapons development. To counter this threat, the USA developed a live vaccine strain (LVS), that showed efficacy in humans against inhalation of virulent Ftt. However, the breakthrough dose was fairly low, and protection waned with time. These weaknesses triggered extensive research for better vaccine candidates. Previously, we showed that deleting the clpB gene from virulent Ftt strain, SCHU S4, resulted in a mutant that was significantly less virulent than LVS for mice, yet better protected them from aerosol challenge with wild-type SCHU S4. To date, comprehensive searches for correlates of protection for SCHU S4 ΔclpB among molecules that are critical signatures of cell-mediated immunity, have yielded little reward. In this study we used transcriptomics analysis to expand the potential range of molecular correlates of protection induced by vaccination with SCHU S4 ΔclpB beyond the usual candidates. The results provide proof-of-concept that unusual host responses to vaccination can potentially serve as novel efficacy biomarkers for new tularemia vaccines.

Xe/Kr separation is industrially important but remains a daunting issue in chemical separations. Herein, a fluorinated metal-organic framework (MOF), [Ni

Inspired by the unique properties of fluorous compounds, the deliberate replacement of H atoms with F atoms in organic linkers of metal–organic frameworks (MOFs) could be of highly interesting. Herein we rationally developed a fluorinated MOF of JXNU-12(F) derived from the parent MOF of JXNU-12 in the presence of the pore partition agent. Remarkably, H/F substitution maintains the crystal structures of MOFs but dramatically enhances the C2H2/CO2 separation properties. The C2H2 uptake of JXNU-12(F) (298 K and 1 bar) is 1.48 times higher than that of JXNU-12 even though the pore volume of JXNU-12(F) is 84% of JXNU-12. Whereas both MOFs exhibit the same CO2 uptakes under the same conditions. The C2H2/CO2 adsorption selectivity of JXNU-12(F) at 1 bar and 298 K is 2 times that of JXNU-12, emphasizing the importance of fluorine substitution. An excellent C2H2/CO2 separation with a large C2H2 captured amount of 4.7 mmol g−1 was achieved with JXNU-12(F), ranking among the best-performing MOFs. The significant performance enhancement in JXNU-12(F) is rationalized by the large electronegativity and polarizability of fluorine groups exposed on the pore surfaces and the well-matched pore spaces generated by pore partition for trapping C2H2, which collaboratively enhance framework-C2H2 interactions as revealed by computional simulations.

The novel sulfonate-carboxylate ligand of 5,7-disulfonate-1,4-naphthalenedicarboxylic acid (H4-DSNPDC) was synthesized, and its series of lanthanide compounds {[Ln3(μ2-OH)(DSNPDC)2(H2O)x]·yH2O}n (J...

A novel fluorinated biphenyldicarboxylate ligand of 3,3',5,5'-tetrafluorobiphenyl-4,4'-dicarboxylic acid (H2-TFBPDC) and its terbium metal-organic framework, {[Tb2(TFBPDC)3(H2O)]·4.5DMF·0.5H2O}n (denoted as JXNU-6), were synthesized. JXNU-6 exhibits a three-dimensional (3D) framework built from one-dimensional (1D) terbium carboxylate helical chains bridged by TFBPDC2- linkers. The 3D framework of JXNU-6 features 1D fluorine-lined channels. The gas adsorption experiments show that the activated JXNU-6 (JXNU-6a) displays distinct adsorption behavior for propyne (C3H4) and propylene (C3H6) gases. The effective removal of a trace amount of C3H4 from C3H6 was achieved by JXNU-6a under ambient conditions, which is demonstrated by the column-breakthrough experiments. The modeling studies show that the preferential binding sites for C3H4 are the exposed F atoms on the pore surface in 1D channels. The strong C-H···F hydrogen bonds between C3H4 molecules and F atoms of TFBPDC2- ligands dominate the host-guest interactions, which mainly account for the excellent C3H4/C3H6 separation performance of JXNU-6a. This work provides a strategy for specific recognition toward C3H4 over C3H6 through the C-H···F hydrogen bond associated with the fluorinated organic ligand.

Due to the intrinsic coordination preference of the linear uranyl unit, uranyl-organic frameworks (UOFs) are generally prone to exhibiting low-dimensional structures. Reactions of uranyl nitrate with biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid dipotassium salt (K2H2BPDSDC) under different conditions led to three UOFs, namely, {(Me2NH2)[K2(UO2)3(μ3-O)(μ3-OH)2(μ2-OH)(BPDSDC)(H2O)3]·4DMF}n (1), {[K2(UO2)(μ3-O)(BPDSDC)0.5(H2O)2]}n (2), and {(Me2NH2)2.5[K1.5(UO2)(BPDSDC)1.5(H2O)3]}n (3). Compounds 1 and 2 contain one-dimensional (1D) ribbon structures formed from UO22+ units bridged by μ3-O atoms and carboxylate groups. The 1D ribbons in 1 are linked by K+ atoms to form a two-dimensional (2D) layer, which is further pillared by the biphenyl units to give a three-dimensional (3D) framework. For 2, the oxygen atoms of UO22+ units in each 1D ribbon bridge the K+ atoms to form four -[K-O-K]n- infinite chains located above and below the ribbon. The 1D ribbons in 2 are bridged by sulfonate groups to generate a 3D substructure featuring 1D channels occupied by biphenyl moieties. In 3, each mononuclear [(UO2)(COO)3] unit is bridged by three K+ atoms to form a 3D substructure featuring 1D small left-handed and large righted helical channels occluded by biphenyl moieties. Compound 2 exhibits an excellent proton conductivity with the highest conductivity of 1.07 × 10-3 S cm-1. The inner walls of 1D channels of 2 are full of the hydrophilic sulfonate groups, which boost enrichment of the guest water molecules, thus resulting in a high proton conductivity. Finally, temperature dependence of fluorescent studies showed that compounds 1 and 2 display the characteristic uranyl emissions. This work presents the elegant examples of the rarely explored 3D UOFs and expands the potentials of UOFs.

The separation of C2H2 and CO2 is of industrial significance but is highly challenging due to their close similarities in physical–chemical properties. Metal–organic frameworks (MOFs) with tailored pore structures and tunable pore surfaces for the separation of C2H2/CO2 mixture are described in this perspective article. In terms of adsorption selectivity, MOF is classified into C2H2-selective MOF and CO2-selective MOF, which are discussed separately. Herein, we intend to present a short summary of the important advancements in C2H2/CO2 separation with MOFs. The relationship between the separation performance and structural features of MOFs, together with the separation mechanisms, has been discussed in detail. The challenges, research trends and opportunities in C2H2/CO2 separation with MOFs are highlighted.

Two rare-earth (RE) metal-organic frameworks (MOFs) formulated as {(Me

A novel metal-organic framework (MOF) of [Co8(OH)4(TCA)4(H2O)4]n (abbreviation: JXNU-9) based on the unique octanuclear Co8(μ3-OH)4 clusters linked by 4,4',4″-nitrilotribenzoate (TCA3-) ligands featuring small caged structures and one-dimensional channels was prepared and characterized. JXNU-9 shows a high C2H6 uptake capacity of 3.60 mmol g-1 (4.46 mmol cm-3) at 298 K and 1 atm with a small isosteric heat of adsorption (23.6 kJ mol-1) and a moderate C2H6/C2H4 adsorption selectivity of 1.7, resulting in excellent C2H6/C2H4 separation performance. The pore walls decorated by plenty of aromatic rings provide π-electron-cloud-surrounding environments to accommodate the large polarizable C2H6 molecules. The calculations demonstrate that the rich π-systems in JXNU-9 facilitate an adsorption affinity for large C2H6 molecules through multiple C-H···π interactions. Additionally, the open metal sites located in the concave pores with a close Co···Co separation (4.21 A) in octanuclear Co8(μ3-OH)4 clusters make the open metal sites inaccessible for the C2H4 molecule with a kinetic diameter of 4.163 A. Thus, the annihilation of open metal sites in this structure is achieved, which further facilitates the C2H6-selective C2H6/C2H4 separation.

Compound {(Me2NH2)3[Eu7(μ3-O)2(TBAPy)5(H2O)6]·12.5DMF}n (JXNU-5), constructed from the 1,3,6,8-tetrakis(4-carboxylphenyl)pyrene (TBAPy4–) ligand and one-dimensional (1D) europium carboxylate rods, is presented. JXNU-5 has a three-dimensional framework with 1D channels. The strong coordination bonds between EuIII ions with high charge densities and carboxylate O atoms as well as strong π···π-stacking interactions between pyrenes lead to a water-resistant JXNU-5, which was verified by powder X-ray diffraction and surface area measurements. The breakthrough simulations and experiments demonstrate that an efficient C2H2/CO2 (50/50 mixture) gas separation at ambient conditions was achieved with JXNU-5. The calculation results show that the dominating interactions between the absorbed C2H2 molecules and host framework are hydrogen bonds associated with the carboxylate O atoms exposed on the pores. Thus, an elegant example of a water-stable metal–organic framework for effective C2H2/CO2 separation is demonstrated.

A π-rich aromatic organic ligand, 4'-(3,5-dicarboxyphenyl)-2,2′,6′,2″-terpyridine (H2-DCPTP), and four new lanthanide coordination polymers, {[Ln(DCPTP)(NO3)]·(H2O)}n (Ln = Tb, Eu, Gd) and {[Tb0.9064Eu0.0936(DCPTP)(NO3)]·(H2O)}n (termed Tb0.9064Eu0.0936-DCPTP), were prepared. Compound {[Ln(DCPTP)(NO3)]·(H2O)}n is a 3D framework based on the dinuclear Ln2(μ2-COO)2] units linked by the tridentate DCPTP2− ligands. The H2-DCPTP ligand with an appropriate triplet excited state confirmed by DFT calculations and experiments, is a light-harvesting ligand for efficiently sensitizing of Tb3+ and Eu3+ simultaneously, thus enhancing the overall luminescent properties of Tb0.9064Eu0.0936-DCPTP. The Tb0.9064Eu0.0936-DCPTP behaves as a high-performance luminescent thermometer ranging from 150 to 300 K with a large relative thermal sensitivity (Sm) of 21.5% K−1 and a high energy transfer efficiency (η) of 84% at 300 K.

Two coordination polymers, {[Ln2(BPDSDC)(BDC)(H2O)6]·4H2O}n (Ln = Tb(1) and Eu(2)), constructed from biphenyl-3,3′-disulfonyl-4,4′-dicarboxylate (BPDSDC4–) and 1,4-benzenedicarboxylate (BDC2–) ligands were synthesized and structurally characterized. The solid state structure of {[Ln2(BPDSDC)(BDC)(H2O)6]·4H2O}n consists of one-dimensional (1D) Ln-BPDSDC double chains and two-dimensional (2D) Ln-BDC squares featuring the Ln2(COO)4 paddle-wheel units and the nanosized grids. Each grid of the 2D squares is threaded by a 1D Ln-BPDSDC double chain, wherein the two parts are interacted through coordination bonds between lanthanide centers of the 2D squares and sulfonate oxygen atoms from 1D chains. Thus the 1D Ln-BPDSDC double chains are threaded through the 2D squares stacked in an eclipsed fashion to give a three-dimensional (3D) distinct architecture. The two compounds emit the characteristic Tb(III) and Eu(III) emissions in the solid state, respectively. Temperature-dependent luminescent studies show the emission intensities for both compounds decrease as temperature increases, which indicates these compounds have the potential for sensing temperature.

An inorganic-organic hybrid compound (H2DPA)2(SiF6) (1) constructed from the di(pyridine-4-yl)amine (DPA) ligands and octahedral SiF62− anions was presented. The protonated H2DPA cations and SiF62− anions are linked by the N H⋯F hydrogen bonds to give a one-dimensional (1D) helical chain, which is further linked by the N H⋯F hydrogen bonds to generate a three-dimensional (3D) framework featuring helical chains. Compound 1 crystallizes in an acentric space group and exhibits a phase-matchable second-harmonic-generation (SHG) response of 1.4 times that of potassium dihydrogen phosphate (1.4 × KDP). The nonlinear organic ligand with inherent dipole and the distorted [SiF6] octahedra, as well as the helical chains in a parallel packing mode contribute the SHG activity for 1.

Two thorium–organic frameworks of [Th6O4(OH)4(TFBPDC)6(H2O)6]n (Th-TFBPDC) and [Th6O4(OH)4(TFBPDC)4(HCOO)4(H2O)6]n (Th-TFBPDC-i) constructed from the 3,3′,5,5′-tetrakis(fluoro)biphenyl-4,4′-dicarbo...

Three cadmium(II) coordination polymers constructed from 5,7-disulfonate-1,4-naphthalenedicarboxylate and N-containing ligands, {[Cd2(DSNPDC)(phen)(H2O)4]·2.5H2O}n (1), {[Cd2(DSNPDC)(phen)2(H2O)4]·3H2O}n (2) and [Cd2(DSNPDC)(bpy)2(H2O)4]n (3) (H4-DSNPDC = 5,7-disulfonate-1,4-naphthalenedicarboxylic acid, phen = 1,10-phenanthroline, and bpy = 2,2′-bipyridine), were synthesized and characterized. Compound 1 displays a two-dimensional (2D) layered structure. In 2 and 3, the dinuclear [Cd2(COO)2] units are connected by DSNPDC4– ligands to generate one-dimensional (1D) chains. Due to the presence of the terminal chelating phen/bpy ligands, all compounds show low dimensional structures. Compounds 1–3 exhibit fluorescence emissions centered at 378, 419 and 376 nm, respectively, which are assigned to ligand-centered emissions or ligand-to-metal charge transfer.

The phenomenon and potential mechanisms of trans-kingdom RNA silencing (or RNA interference, RNAi) are among the most exciting topics in science today. Based on trans-kingdom RNAi, host-induced gene silencing (HIGS) has been widely applied to create crops with resistance to various pests and pathogens, overcoming the limitations of resistant cultivars. However, a lack of transformation technology in many crops limits the application of HIGS. Here, we describe the various fates of trans-kingdom RNAs in recipient organisms. Based on the assumption that small RNAs can be transferred between the host and its microbiome or among microbiome members, we propose a possible alternative strategy for plant protection against pathogens without the need for crop genetic modification., This review briefly summarizes recent progress in trans-kingdom RNAs and describes the various fates of trans-kingdom RNAs in recipient organisms. Based on the assumption that trans-kingdom RNAs can transfer to different recipients and be retained in the recipient genome, a strategy for using beneficial microbes to generate sRNAs for crop protection is proposed.

The diphenylsulfone-3,3′-disulfo-4,4′-dicarboxylic acid (H4-DPSDSDC) ligand and its coordination polymers, [K2Zn(C14H6S3O12)(H2O)4]n (1) and {[Cu3(μ3–OH)2(C14H6S3O12)(H2O)3(DMF)]·3(H2O)}n (2) (C14H...

Receptor-mediated transcytosis (RMT) is a principal pathway for transport of macromolecules essential for brain function across the blood-brain barrier (BBB). Antibodies or peptide ligands which bind RMT receptors are often co-opted for brain delivery of biotherapeutics. Constitutively recycling transferrin receptor (TfR) is a prototype receptor utilized to shuttle therapeutic cargos across the BBB. Several other BBB-expressed receptors have been shown to mediate transcytosis of ligands including insulin receptor (INSR) and insulin-like growth factor-1 receptor (IGF1R), lipid transporters LRP1, LDLR, LRP8 and TMEM30A, solute carrier family transporter LAT1 (subunit CD98hc) and leptin receptor (LEPR). In this study, we analyzed expression patterns of genes encoding RMT receptors in isolated brain microvessels, brain parenchyma and peripheral organs of the mouse and the human using RNA-seq approach. IGF1R, INSR and LRP8 were highly enriched in mouse brain microvessels compared to peripheral tissues. In human brain microvessels only INSR was enriched compared to either the brain or the lung. The expression levels of SLC2A1, LRP1, IGF1R, LRP8 and TFRC were significantly higher in the mouse compared to human brain microvessels. The protein expression of these receptors analyzed by quantitative Western blot and immunofluorescent staining of the brain microvessels correlated with their transcript abundance. This study provides a molecular transcriptomics map of key RMT receptors in mouse and human brain microvessels and peripheral tissues, important to translational studies of biodistribution, efficacy and safety of antibodies developed against these receptors.

While the neuronal underpinnings of autism spectrum disorder (ASD) are being unraveled, vascular contributions to ASD remain elusive. Here, we investigated postnatal cerebrovascular development in the 16p11.2df/+ mouse model of 16p11.2 deletion ASD syndrome. We discover that 16p11.2 hemizygosity leads to male-specific, endothelium-dependent structural and functional neurovascular abnormalities. In 16p11.2df/+ mice, endothelial dysfunction results in impaired cerebral angiogenesis at postnatal day 14, and in altered neurovascular coupling and cerebrovascular reactivity at postnatal day 50. Moreover, we show that there is defective angiogenesis in primary 16p11.2df/+ mouse brain endothelial cells and in induced-pluripotent-stem-cell-derived endothelial cells from human carriers of the 16p11.2 deletion. Finally, we find that mice with an endothelium-specific 16p11.2 deletion (16p11.2ΔEC) partially recapitulate some of the behavioral changes seen in 16p11.2 syndrome, specifically hyperactivity and impaired motor learning. By showing that developmental 16p11.2 haploinsufficiency from endothelial cells results in neurovascular and behavioral changes in adults, our results point to a potential role for endothelial impairment in ASD.

The novel sulfonate-carboxylate ligand of 5,7-disulfonate-1,4-naphthalenedicarboxylic acid (H

Receptor-mediated transcytosis (RMT) is a principal pathway for transport of macromolecules essential for brain function across the blood-brain barrier (BBB). Antibodies or peptide ligands which bind RMT receptors are often co-opted for brain delivery of biotherapeutics. A constitutively recycling transferrin receptor (TfR) is a prototype receptor utilized to shuttle therapeutic cargos across the BBB. Several other BBB-expressed receptors have been shown to mediate transcytosis of ligands including insulin receptor (INSR) and insulin-like growth factor-1 receptor (IGF1R), lipid transporters LRP1, LDLR, LRP8 and TMEM30A, solute carrier family transporter LAT1 (subunit CD98hc) and leptin receptor (LEPR). In this study, we analyzed expression patterns of genes encoding RMT receptors in isolated brain microvessels, the brain and peripheral organs of the mouse and the human using RNAseq approach. IGF1R, INSR and LRP8 were highly enriched in the mouse brain microvessels compared to peripheral tissues. In the human brain microvessels only INSR was enriched compared to either the brain or the lung. The expression levels of LRP1, IGF1R, LRP8 and TFRC were significantly higher in the mouse compared to the human brain microvessels. The protein expression of these receptors analyzed by quantitative Western blot and immunofluorescent staining of the brain microvessels correlated with their transcript abundance. This study provides a molecular transcriptomics map of key RMT receptors in mouse and human brain microvessels and peripheral tissues, important sot translational studies of biodistribution, efficacy and safety of antibodies developed against these receptors.

Two coordination polymers, [Co2(DPSDSDC)(H2O)6]n (1) and {[Cu4(DPSDSDC)2(bpy)4(H2O)2]·11.5(H2O)}n (2) (H4-DPSDSDC =diphenylsulfone-3,3′disulfo-4,4′-dicarboxylic acid and bpy = 4,4'-bipyridine), were prepared and characterized. Compound 1 shows a two-dimensional (2-D) layered structure featuring hydrophilic interlayered spaces and a moderate proton conductivity of 5.22 × 10−5 S cm−1 at 95% RH and 85 °C. Compound 2 contains the linear trinuclear Cu3 units and mononuclear copper(II) units, which are connected by diphenylsulfone-3,3′-disulfo-4,4′-dicarboxylate and 4,4'-bipyridine ligands to afford a 3-D framework. Compound 2 exhibits low proton conductivity resulting from the hydrophobic aromatic rings on the pore walls.

A 3D coordination polymer [CdK6(μ2-H2O)2(BODSDC)2(H2O)]n (1) based on the novel benzophenone-3,3′-disulfonyl-4,4′-dicarboxylate (BODSDC4−) ligand was synthesized and structurally characterized. The carboxylate and sulfonate groups of the organic ligands as well as the bridging water molecules connect the Cd2+ and K+ ions to produce a 2D layer, which is linked by the benzophenone moieties to give a 3D pillared framework. Compound 1 crystallizes in an acentric space group of Cc and has a large second-harmonic-generation (SHG) response of 1.3 times that of potassium dihydrogen phosphate (KDP) in the particle size of 25–210 μm. Further SHG measurements revealed that the material is type-I phase-matchable. The observed SHG efficiency is associated with the unsymmetrical geometry of the organic ligand and the distorted coordination polyhedrons of metal centers.

A novel compound, [Ni(DCPTP)]n (termed Ni-DCPTP), based on the 4'-(3,5-dicarboxyphenyl)-2,2',6',2 `'-terpyridine (DCPTP2-) ligand was presented here. Ni-DCPTP has a three-dimensional structure with a the topology featuring one-dimensional (1D) helical channels. Ni-DCPTP shows an efficient removal of a trace amount of C2H2 from a C2H2/C2H4 (1/99) mixture with an excellent C2H4 productivity as demonstrated by both the transient breakthrough simulations and breakthrough experiments, generating the polymer-grade C2H4 gas (C2H2

Nonlinear optical switches that reversibly convert between on/off states by thermal stimuli are promising for applications in the fields of photoelectronics and photonics. Currently one main drawback for practical application lies in the control of their switch temperature, especially for the temperature range near room temperature. By mixed melting treatment, here we describe an alloy-like nonlinear optical switch with tunable switch temperature via a dual solid solution approach within the coordination polymer system. We initially prepare a coordination polymer (i-PrNHMe2)[Cd(SCN)3], which functions as a high-contrast thermoresponsive nonlinear optical switch originating from a phase transition at around 328 K. Furthermore, by taking advantage of a synergistic dual solid solution effect, the melt mixing of it with its analogue (MeNHEt2)[Cd(SCN)3], which features an unequal anionic chain templated by an isomeric ammonium, can afford coordination polymer solid solutions with switch temperatures that are tunable in a range of 273–328 K merely by varying the component ratio., Switching of nonlinear optical signals is attractive for photoelectronics and photonics, but development is hindered by a lack of control over the switch temperature. Here the authors report a coordination polymer system that serves as an alloy-like nonlinear optical switch with a tunable switch temperature.

An anionic three-dimensional metal-organic framework of JXNU-4 with one-dimensional channels occupied by the extraframework dimethylammonium cations was chosen as a parent compound to host Eu3+ cations by uncoordinated carboxylate oxygen atoms in its pores through a cation exchange experiment. The Eu3+-incorporated sample Eu3+@JXNU-4 is structurally characterized and displays excellent Eu3+ luminescence and good fluorescence stability in aqueous solution, which is resulted from the sensitization and protection provided by the parented framework. The Eu3+@JXNU-4 was developed as a fluorescent probe for urine 1-hydroxypyrene (1-HP), which is a biomarker of polycyclic aromatic hydrocarbons (PAHs) carcinogens and represents the internal dose of PAHs exposure in the human body. In the presence of 1-HP, the 1-HP emission emerges and Eu3+@JXNU-4 exhibits 1-HP- and Eu3+-based dual emission. The intensity of the 1-HP emission increases with the concentration of 1-HP increasing, while the Eu3+ emission recedes in the meantime. The ratio value of 1-HP emission at 502 nm (I502) and Eu3+ emission at 616 nm (I616) versus the concentration of 1-HP reveals a good linear relationship, which indicates the Eu3+@JXNU-4 is an excellent candidate for ratiometric fluorescence sensing for 1-HP. Finally, the fluorescence mechanism was discussed.

In this study, an antimicrobial peptide composed of three tandem repeats of Mytichitin-A (3 × Mytichitin-A) with a designed molecular weight of approximately 25 kDa was expressed in the green alga Chlamydomonas reinhardtii. The yield of 3 × Mytichitin-A reached 0.28% of the total soluble protein of the 3 × Mytichitin-A-expressing transgenic cells and the expression level was stable following continuous passaging of the cells for six months. Compared to its natural and yeast-produced recombinant counterparts, which showed a very low level of growth inhibition of gram-negative bacteria, the 3 × Mytichitin-A inhibited the growth of gram-negative bacteria at a minimum inhibition concentration value ranging between 60 and 80 μg/ml. The expressed 3 × Mytichitin-A did not show toxicity to HEK293 cells. Its bioactivity was hardly affected by temperature and pH but was impaired to some extent by the proteinase treatment. Taken together, our study showed that C. reinhardtii can be used as a cellular factory to produce bioactive Mytichitin-A in a multimeric format.

Benefiting from its bent molecular structure, 3,6-pyridazinyl contained tetracationic cyclophane ( 1 ) is synthesized by template-directed method with high isolated yield up to 92%. This template-directed strategy is further utilized to efficiently construct [2]rotaxane.

Reactions of Cd(NO3)2·4H2O with 2-quinolinecarboxylic acid (H-QLC) in the presence of 1,4-benzenedicarboxylic acid (H2-BDC) or 1,3,5-benzenetricarboxylic acid (H-BTC) in DMF/H2O solvent afforded two compounds, namely, [Cd(QLC)(BDC)1/2(H2O)]n (1) and [Cd(QLC)(BTC)1/3]n (2). Both compounds are two-dimensional (2D) frameworks but feature different cadmium-carboxylate clusters as a result of the presence of the polycarboxylate ligands with different geometries and coordination preference. The dinuclear Cd2(QLC)2 units in 1 are bridged by the pairs of bridging water ligands to give a one-dimensional (1D) chain, which is further linked by the second ligand of BDC2– to form a 2D structure. Compound 2 is constructed from unique hexanuclear macrometallacyclic Cd6(QLC)6 clusters, which are linked by the surrounding BTC3– ligands to generate a 2D structure. Photoluminescence studies showed both compounds exhibit ligand-centered luminescent emissions with emission maxima at 405 and 401 nm, respectively.

A metal–organic framework (MOF), {(Me2NH2)2[Zn6(μ4-O)(ad)4(BPDC)4]}n (JXNU-4; ad– = adeninate), with an anionic three-dimensional (3D) framework constructed from one-dimensional (1D) columnar [Zn6(ad)4(μ4-O)]n secondary building units (SBUs) and 4,4′-biphenyldicarboxylate (BPDC2–) ligand, was prepared. The anionic 3D framework has 1D square channels with an aperture of about 9.8 A and exhibits a carboxylate-O-decorated pore environment. The microporous nature of JXNU-4 was established by the N2 adsorption data, which gives Langmuir and Brumauer–Emmett–Teller surface areas of 1800 and 1250 m2 g–1, respectively. Noticeably, JXNU-4 shows potential as a separation agent for the selective removal of propane and ethane from natural gas with high selectivities of 144 for C3H8/CH4 (5:95) and 14.6 for C2H6/CH4 (5:95), respectively. Most importantly, JXNU-4 shows an aqueous-phase adsorption of a positively charged ion of methylene blue selectively over a negatively charged ion of resorufin, which is pertinent to th...

Reactions of DyCl3·6H2O or Dy2O3 with 2-quinolinecarboxylic acid (H-QLC) yielded two compounds, namely, [Dy4(QLC)12(H2O)6]·4H2O (1) and [Dy(QLC)3(H2O)2]n (2). Compound 1 is a linear tetranuclear structure with one central [Dy2(QLC)4(H2O)4] subunit and two terminal [Dy(QLC)3(H2O)] subunits linked by bridging QLC− ligands. Compound 2 has a one-dimensional (1D) chain wherein the [Dy(QLC)2] unit formed by two QLC− ligands chelating a Dy(III) ion is connected by the bridging QLC− ligands. Compounds 1 and 2 exhibit slow magnetic relaxation behaviour in the absence of a static magnetic field, which is rarely observed in lanthanide-carboxylate compounds. During the structural evolution from a linear Dy4 cluster of 1 into a 1D chain of 2, the anisotropy energy barrier (Ueff) is enhanced from 45.4(2) to 144.2(1) K. Though the Dy(III) centers in 1 and 2 all are eight-coordinated with square antiprismatic coordination environments, the higher energy barrier observed for 2 could be the result of a more favorable crystal field for the Dy(III) ions in 2.

A 3D terbium-organic framework [TbK(BPDSDC)(DMF)(H2O)2]n (1) with the bifunctional carboxylate-sulfonate ligand of biphenyl-3,3′-disulfonyl-4,4′-dicarboxylate (BPDSDC4 −) was synthesized and characterized. The Tb3 + and K+ ions are briged by the carboxylate and sulfonate groups to give a 2D layer, which is linked by the biphenyl moieties to form the 3D pillared framework with the sulfonate groups pointing at the pores. The sulfonate groups on the pores act as the basic sites for the Cr3 + ion sensing by luminescence quenching, highlighting the potential for recognition of Cr3 + ion for compound 1 with the characteristic bright green color.