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Lung cancer is still the most common cancer globally. Early screening remains the key to improve the prognosis of patients. There is currently a lack of specific and sensitive methods for early screening of lung cancer. In recent years, studies have found that microRNA plays an important role in the occurrence and development of lung cancer and become a biological target in the early diagnosis of lung cancer. In this study, lung cancer cells, subcutaneous xenografts of lung cancer in nude mice, and Lox-Stop-lox K-ras G12D transgenic mice were used as models. The transgenic mice displayed the dynamic processes from normal lung tissue to atypical hyperplasia, adenomas, carcinoma in situ and lung adenocarcinoma. It was found that miR-155 and somatostatin receptor 2 (SSTR2) were expressed in all the disease stages of transgenic mice. Through molecular beacon (MB) technology and nanotechnology, chitosan-molecular beacon (CS-MB) nanoparticles and targeted octreotide (OCT) were conjugated and synthesized. The octreotide-conjugated chitosan-molecular beacon nanoparticles (CS-MB-OCT) can specifically bind to SSTR2 expressed by the lung cancer cells to achieve the goal of identification of lung cancer cells and imaging miR-155 in vivo and in vitro. Fluorescence imaging at different disease stages of lung cancer in Lox-Stop-lox K-ras G12D transgenic mice was performed, and could dynamically monitor the occurrence and development of lung cancer by different fluorescence intensity ranges. The current research, in turn, provides new idea, new method, and new technology for the early screening of lung cancer.

Lung cancer is the major cause of cancer-related deaths worldwide, thus developing effective methods for its early diagnosis is urgently needed. In recent years, microRNAs (miRNAs, miR) have been reported to play important roles in carcinogenesis and have become potential biomarkers for cancer diagnosis and treatment. Molecular beacon (MB) technology is a universal technology to detect DNA/RNA expression in living cells. As a natural polymers, chitosan (CS) nanoparticles could be used as a carrier for safe delivery of nucleic acid. In this study, we developed a probe using nanoparticles of miR-155 MB self assembled with CS (CS-miR-155 MB) to image the expression of miR-155 in cancer cells. Hybridization assay showed that the locked nucleic acid (LAN) modified miR-155 MB could target miR-155 effectively and sensitively. The miR-155 MB self-assembly with CS nanoparticles formed stable complexes at the proper weight ratio. The CS nanoparticles showed higher fluorescence intensity and transfection efficiency than the lipid-based formulation transfection agent by confocal microscopy and flow cytometry analysis. The CS-MB complexes were found to be easily synthesized and exhibited strong enzymatic stability, efficient cellular uptake, high target selectivity and biocompatibility. The CS-MB complexes can also be applied in other cancers just by simply changing for a targeted miRNA highly expressed in those cancer cells. Therefore, it is a promising vehicle used for detecting miRNA expression in living cells.

In recent years, organic-inorganic hybrid materials have demonstrated exceptional performance in nonlinear optics, attracting widespread attention. However, there are relatively few examples of coordination compounds synthesized with Cu as the metal center that exhibit excellent nonlinear optical properties. In this study, we successfully synthesized a pair of enantiomers named R/S-Cu2I2 by reacting chiral ligands with CuI. The crystal structure reveals a one-dimensional copper-iodide chain structure built by Cu2I2 clusters, and its ordered arrangement in space provides not only a strong second harmonic generation (SHG) signal (1.24 × KDP) but also a large birefringence (0.15@1064 nm). Under excitation at 395 nm, the crystals exhibit red fluorescence peaked at 675 nm. The CD spectra of R/S-Cu2I2 show a distinct mirror-symmetric Cotton effect, and their CPL signals are corresponding and opposite in the emission range, with a maximum glum of approximately ±2.5 × 10-3. Theoretical calculations using density functional theory were also carried out to enhance our understanding of the correlation between their structures and optical properties. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of various 3D porous cobalt-organic frameworks are studied. These compounds are shown to exhibit spin-canted antiferromagnetism and field-induced spin-flop transition.

Systematic syntheses, structures, visible luminescence and magnetic properties of a series of new lanthanide hybrids are described. The structures contain trigonal dodecahedral chains and clustered lanthanide oxide ring tunnels and 3D Ln-O-Ln connectivity.

Five novel Zn(II)/Cd(II) coordination polymers (CPs) based on the V-shaped ligand 1H-3,5-bisIJpyrazinyl)- 1,2,4-triazole (Hbpt) and different polycarboxylates, {[Cd(bpt)(H2O)]·ClO4·H2O} (1), {[Cd4(bpt)2(suc)2.5(OH)]· 3H2O} (2), {[Cd4(bpt)3)1,3-bdc)2.5]·4H2O} (3), {[Cd9(bpt)6(1,4-bdc)6(H2O)2]·4H2O} (4) and {[Zn2(bpt)(H3bhc)- (H2O)6]·H2O} (5) (H2suc = succinic acid, 1,3-H2bdc = isophthalic acid, 1,4-H2bdc = terephthalic acid, H6bhc = benzene-1,2,3,4,5,6-hexacarboxylic acid), have been successfully synthesized. Their structures have been characterized using single-crystal X-ray crystallography, powder X-ray diffraction (PXRD) analyses, elemental analyses, IR spectroscopy, and thermogravimetric analyses (TGA). Complex 1 bears a two-dimensional (2D) layered (3,3) network, which is further extended into the resulting three-dimensional (3D) supramolecular architecture via π...π stacking interactions between the terminal pyrazine groups of bpt- ligands. In 2, Cd(II) ions and bpt- ligands construct a 2D Cd-bpt layer and two 1D zigzag chains, which are further connected by suc2- ligands to form a 2D + 1D → 3D (4,5)-connected framework. Complex 3 contains two kinds of grids, and their alternating arrangement gives a final complicated 3,4,5-connected network with a stoichiometry of (3-c)6(4-c)9(5-c)2. In 4, the bpt- ligands act as tetradentate ones to connect neighbouring Cd(II) ions into an infinite 1D Cd-bpt chain. The completely deprotonated 1,4-bdc2- ligands further link the adjacent Cd-bpt chains to generate a novel 3,4,6-connected 3D topological network with (3-c)2(4-c)14(6-c). Complex 5 displays an infinite 1D coordination chain. There are strong π...π stacking interactions between adjacent chains in 5 with a centroid-centroid distance of 3.860 Å and 3.862 Å, resulting in a 3D supramolecular structure. The results show that Hbpt can act as a versatile building block for the construction of various coordination polymers. Moreover, the fluorescence properties of 1-5 in the solid state have also been investigated. [ABSTRACT FROM AUTHOR]

By employment of a tripodal phosphoric carboxylate ligand, tris(4-carboxyl phenyl )phosphin e oxide (H,TPO), two novel porous metal--organic frameworks, namely, [Zn4(μ3OH)2(TPO)2(H2O)2] (l) and [Zn6(μ6-O)(TPO)2] (NO3)4-3H2O (2), have been synthesized by solvothermal methods. Complexes 1 and 2 exhibit three-dimensional microporous frameworks with flu and pyr topologies and possess rare butterfly-shaped Zn4(μ3-OH)2(CO2)6 and octahedral Zn6(μ6-O)(CO2)6 secondary building units, respectively. Large cavities and one-dimensional channels are observed in these two frameworks. Gas-sorption measurements indicate that complex 2 has a good H2 uptake capacity of 171.9 cm g-1 (1.53 wt %) at 77 K and 1.08 bar, and its ideal adsorbed solution theory calculation predicts highly selective adsorption of CO2 over N2 and CH4. Furthermore, complexes 1 and 2 exhibit excellent blue emission at room temperature. [ABSTRACT FROM AUTHOR]

Reaction of europium sulfate octahydrate with p-terphenyl-3,3'',5,5''-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.5H2O}n (1), {[Me2H2N] 2 [Eu2(ptptc)2(H2O)(DMF)]·1.5DMF·7H2O}n (2), and {[Eu(Hptptc)(H2O)4]·0.5DMF·H2O}n (3). Complex 1 exhibits a three-dimensional (3D) metal--organic framework based on {Eu2(μ 2-COO)2 (COO)4}n chains, complex 2 shows a 3D metal--organic framework constructed by [Eu2(μ 2-COO) 2(COO)6]2- dimetallic subunits, and complex 3 features a 2D layer architecture assembling to 3D framework through π···π interactions. All complexes exhibit the characteristic red luminescence of Eu(III) ion. The triplet state of ligand H4ptptc matches well with the emission level of Eu(III) ion, which allows the preparation of new optical materials with enhanced luminescence properties. The luminescence properties of these complexes are further studied in terms of their emission quantum yields, emission lifetimes, and the radiative/nonradiative rates. [ABSTRACT FROM AUTHOR]

Reactions of a tripodal ligand, N,N′,N″-tris(3-pyridinyl)phosphoric triamide (TPPA), and a series of transition-metal ions result in the assembly of five discrete M6L8 coordination cages [M6(TPPA)8(H2O)12](ClO4)12·57H2O [M = Ni2+ (1), Co2+ (2), Zn2+ (3), Cd2+ (4)] and [Pd6(TPPA)8]Cl12·22H2O (5). X-ray structural analyses reveal that the cages have large internal cavities and flexible windows. The flexible ligand TPPA adopts the syn conformation in cages 1-4, but it transforms to the anti conformation in cage 5. Because of the conformational transformation, the sizes of the windows and the volume of the internal cavity of cage 5 are increased. 1H NMR and electrospray mass spectrometric studies show that cage 5 maintains its structural integrity in solution. Additionally, compounds 3 and 4 exhibit strong blue fluorescent emissions, which are 1 order of magnitude higher than that of the free ligand. [ABSTRACT FROM AUTHOR]

Four nickel(II)-5-aminodiacetic isophthalate coordination polymers with different auxiliary ligands are synthesized by the solvothermal method. {[Ni4(adip)2(H2O)10]·6H2O}n(1) (H4adip = 5-aminodiacetic isophthalic acid) is a supermolecular structure assembled by two-dimensional (2D) layers, and it can be viewed as a novel binodal (3,4)-connected topological net with a Schläfli symbol of (4.6.8)4(62.82.102) which has not been reported in the literature. When dipyridyl auxiliary ligands with different spacers are engaged in the reactions to pillar the 2D layers of 1, the 3D frameworks of complexes 2–4are obtained. {[Ni3(Hadip)2(bpy)2(H2O)4]·9H2O}n(2) (bpy = 4,4′-bipyridine) was crystallographically characterized to be a three-dimensional (3D) coordination network with SPC519 type topology. {[Ni8(adip)4(bpy)(H2O)18]·10H2O}n(3) as a 3D framework exhibits a scarcely reported (3,5)-connected topology with a Schläfli symbol of (4.6.8)4(62.86.102). {[Ni2(adip)(bpp)(H2O)2]·2H2O}n(4) (bpp = 1,3-bis (4-pyridyl)propane) features a 3D chiral framework composed of the achiral reagents adip4–and bpp, resulting a new (4.52)(4.53.72.84) topology. Meanwhile, the influences of configuration and length of the auxiliary ligands on the structures are investigated. The magnetic studies indicate antiferromagnetic behaviors for complexes 1and 3, and as their metal–metal distances in the dinulcear units increase the antiferromagnetic interactions become stronger. [ABSTRACT FROM AUTHOR]

A series of luminescent lanthanide coordination complexes, [Eu2(hqc)6(H2O)4]·8H2O (1), [Ln2(hqc)6(H2O)2(DMF)2]·2H2O (Ln = Eu (2), Dy (3), Ho (4)), and [Ln2(hqc)6(H2O)4]·2H2O·2DMF (Ln = Ce (5), La (6), Pr (7); Hhqc =2-hydroxyquinoline-4-carboxylic acid), have been synthesized via evaporative crystallization and then characterized by single-crystal X-ray diffraction. Complexes 1−7are nine-coordinated lanthanide(III) complexes with distorted tricapped trigonal prism geometry around each metal center. The dinuclear units in 1−7form the two-dimensional square networks and further extend to three-dimensional supramolecular frameworks through the π−π stacking and strong hydrogen bonding interactions. The optical properties of complexes 1−7in both the solid state and solution state were investigated in detail at room temperature and 10 K. The results show that the Eu3+ions in 1and 2could be highly sensitized by the hqc−ligands and thus emit intense red luminescence with long lifetimes, while complexes 3and 5−7exhibit the characteristic blue luminescence. Furthermore, X-ray diffraction and thermogravimetric analysis of 1−7are also studied, which demonstrate their high purities and good thermal stabilities. [ABSTRACT FROM AUTHOR]

Reactions of 2,2′-dihydroxyl-[1,1′]-binaphthalene-3,3′-dicarboxylate acid (H2bna) with manganese chloride by a solvent or solvothermal method in the presence of pyridine (py) or 4-picoline (pic) give birth to three 1D to 3D frameworks: [Mn(bna)(DMF)2(H2O)2]n·nDMF (1), {(Hpic)2[Mn3(bna)4(C2H5OH)2(H2O)2]·5H2O}n(2), and {(Hpy)2[Mn3(bna)4(py)2(H2O)2]·4H2O}n(3) (DMF = N,N′-dimethylformamide). Crystal structure analyses reveal that 1is a mesomer with equivalent R- and L-helical rectangular tubes constructed from homochiral ligands, which is further assembled into a 3D supramolecular network through hydrogen bonds and C−H···π interactions. Complex 2consists of a (4,4) grid chiral layer structure, while 3features a 3D cubic diamond network with Schläfli symbol 66topology, though they both comprise of [Mn3(μ2-COO)6(COO)2] pinwheel molecular building blocks which act as 4-connected nodes and bna2−as linkers. Magnetic studies indicate that antiferromagnetic couplings exist in both 2and 3. [ABSTRACT FROM AUTHOR]

Five indium(iii) compounds with 2,5-pyridine dicarboxylate ligands: {[4,4′-Hbipy] [In(Hpdc)(H2O)Cl3]·2H2O}n(1), {[4,4′-H2bipy]4[In2(pdc)7(H2O)]·7H2O}n(2), {[4,4′-H2bipy]3[In2(pdc)6(H2O)]·6H2O}n(3), {[In2(pdc)2(bpno)(H2O)2Cl2]·2H2O}n(4) and [In2(pdc)2(2,2′-bipy)Cl2]n(5), (H2pdc = 2,5-pyridine-dicarboxylic acid, 4,4′-bipy = 4,4′-bipyridine, bpno = 4,4′-bipyridine N,N-dioxide, 2,2′-bipy = 2,2′-bipyridine) were hydrothermally or solvothermally synthesized and their structures were determined by X-ray single-crystal diffraction. Compounds 1and 2are both mononuclear structures, which are assembled into 3-D supramolecular structures by various hydrogen bonding; compound 3consists of two types of infinite 1-D indium(iii)-carboxylate chains; compound 4is a 2-D wave-like plane structure formed by bpno linked indium(iii)-carboxylate chains. An unprecedented 3-D chiral framework of compound 5with three kinds of helices along [010] direction is observed, considering that the construction of a chiral structure by rigid achiral ligands is rare. A topological analysis using TOPOS4.0 indicates that compound 5is a unique and novel example of self-penetrated (4,8)-connected binodal lattice with a {32.64}{34.44.58.69.72.8} Schläfli symbol. The above-mentioned compounds were also characterized by X-ray powder diffraction (XRD), thermal gravity analysis (TGA) and photoluminescent studies. [ABSTRACT FROM AUTHOR]

Through an in situ hydrolysis reaction of the bishydrazone ligandH4L1 [H4L1=(HOC6H4)CH=NNHCO(C5H3N)- CONHN=CH(C6H4OH)], in the presence of Fe(III) ions, an interwoven trigonal metallamacrocycle [Fe3L3(H2O)3].9H2O (1) [H3 L = (HOC6H4)CH=NNHCO(C5H3N)CO2H] containing unusually double-layered capsule-likewater hexamerswas obtained and characterized by elemental analysis, FT-IR, TGA, ESI-MS and X-ray crystallography. [ABSTRACT FROM AUTHOR]

Abstract  Single crystals of [W11Ni1P1O39(Hbpy)](H2bpy)2 · 4.25H2O (1) and (W11Zn1P1O39)(H2bpy)2(Hbpy) · 1.5H2O (2) have been hydrothermally synthesized at 160 °C and both characterized by IR, elemental and single-crystal structural analyses. Compound 1 has a ladder-like chain structure by hydrogen bonding interactions, whereas 2 contains an unprecedented chain of Keggin polyoxotungstates by oxo-bridges and form a 2-D layer via hydrogen bonds. [ABSTRACT FROM AUTHOR]

A porous anionic framework with cubic symmetry and multi-intersecting open channels, H2tmdp3In6(btc)8·40H2On (1) (tmdp 4,4‘-trimethylene dipiperidine, H3btc1,3,5-benzenetricarboxylic acid), is reported. Complex1crystallizes in the cubic space group I3d (abc20.3732(8) Å, V8456.2(6) Å3, and Z2). Its cagelike units, In9(btc)11, constitute a large accessible void with 65.4% of the total volume. The cationic guests located in the channels can be exchanged with inorganic ions, such as K, NH4, Ca2, Sr2, and Ba2. [ABSTRACT FROM AUTHOR]

Two 3D lanthanide frameworks, [Ln7(DPA)5(NA)3(μ3-OH)8(H2O)3]·2.5H2O [H2DPA = diphenic acid; HNA = nicotinic acid; Ln = Gd (1), Dy (2)], were synthesized and structurally characterized. They were rarely seen examples of 3D frameworks constructed from heptanuclear trigonal-antiprismatic lanthanide clusters with mixed H2DPA and HNA ligands. Both 1 and 2 show typical antiferromagnetic interactions. Additionally, complex 1 possesses a large magnetocaloric effect of 34.15 J kg-1 K-1. [ABSTRACT FROM AUTHOR]

A luminescent homochiral 3D metal-organic framework, [Cd(dtba)(bpp)]3n (1) (H2dtba = 2,2'-dithiobisbenzoic acid, bpp = 1,3-bis(4-pyridyl)propane), with an unprecedented threefold interpenetrating uniform network (86), constructed from [Cd(dtba)]n single helices and [Cd(bpp)]n double-stranded helices, has been synthesized via hydrothermal reaction. [ABSTRACT FROM AUTHOR]

A luminescent homochiral 3D metal-organic framework, [Cd(dtba)(bpp)]3n (1) (H2dtba = 2,2'-dithiobisbenzoic acid, bpp = 1,3-bis(4-pyridyl)propane), with an unprecedented threefold interpenetrating uniform network (86), constructed from [Cd(dtba)]n single helices and [Cd(bpp)]n double-stranded helices, has been synthesized via hydrothermal reaction. [ABSTRACT FROM AUTHOR]

Two MMOFs with double-walled tubular structures have been presented: [In(aip)(µ2-OH)]n·3nH2O (1) and [In2(Hsip)2(µ2-OH)2(H2O)]n·2nH2O (2) (H2aip = 5-aminoisophthalic acid, NaH2sip = 5-sulfoisophthalic acid monosodium salt), which both consisted of alternatively arranged left- and right-handed nested coaxial bi-strand helices interconnected by the ligands. The channels in complex 2are functionalized by the unligated sulfonate anion groups as Lewis base functional groups which also act as windows of the channels. [ABSTRACT FROM AUTHOR]

A novel three-dimensional (3D) microporous lanthanide−organic framework [Nd(2,5-pydc)(Ac)(H 2O)] n·2 nH 2O ( 1) has been prepared under hydrothermal conditions. The results of an X-ray crystallographic analysis revealed that compound 1has a 3D nanotubular structure. From the topological point of view, the intricate 3D framework of compound 1can be specified by the Schläfli symbol (4 26 38) as a zeolite ABW net. The H 2adsorption isotherm at 77 K shows an uptake of 132 cm 3g −1at 1.0 atm. [ABSTRACT FROM AUTHOR]

In the title compound, C14H8O6S, the dihedral angle of the two phthalic fragments is 76.41 (10) Å. The molecule lies on a mirror plane. The C atoms of the benzene rings have bond lengths in the range 1.384 (2)–1.490 (2) Å and bond angles in the range 118.80 (16)–121.64 (15)°. Centrosymmetric rings of hydrogen-bonded carboxyl groups connect molecules into a zigzig chain. [ABSTRACT FROM AUTHOR]

The title compound, (C2H8N)2(C8H20N)2[H2V10O28], contains two crystallographically independent centrosymmetric polyvanadate clusters, each with a composition [V10O28H2]4−, with the H atoms attached to μ2-O atoms. A variety of O—H⋯O and N—H⋯O hydrogen bonds generate a two-dimensional network. [ABSTRACT FROM AUTHOR]