Search

Organoid culture is a popular model to study gene function as the easy manipulating and time saving compared with in vivo experiments. This is widely used in auditory system for studying supporting cells (SCs) or hair cells (HCs) as only very few SCs or HCs can be harvested in both human and murine cochlea. However, the use of organoids is still a challenge due to the low efficiency in genetic modification. Here we took Lin28b as an example and compared Lin28b gain-of-function (GOF) and loss-of-function (LOF) with different genetic engineering methods and found that TetOn induced GOF or LOF was more efficient compared with lipofection or lentiviral transduction in the experimental conditions we used. Cell apoptosis in TetOn induction system was lowest compared with the other methods in this study. Our study is the first to compare the efficiency of different genetic engineering techniques in cochlear organoid culture, which may also apply to organoids established with other tissues.

By 5-h reaction of cis-[RuIICl2(DMSO)4] (M2) with K10[α2-P2W17O61] (M3) in ice-cooled, HCl-acidic aqueous solution, a water-soluble 1:2-type diamagnetic ruthenium(II) complex of formula K18[RuII(DM...

Polyoxometalates (POMs) show considerable catalytic performance toward the selective oxidation of alkenes to aldehydes, which is commercially valuable for the production of pharmaceuticals, dyes, perfumes, and fine chemicals. However, the low specific surface area of POMs as heterogeneous catalysts and poor recyclability as homogeneous catalysts have hindered their wide application. Dispersing POMs into metal-organic frameworks (MOFs) for the construction of POM-based MOFs (POMOFs) suggests a promising strategy to realize the homogeneity of heterogeneous catalysis. Herein, we report two new POMOFs with chemical formulas of [Co(BBTZ)2][H3BW12O40]·10H2O (1) and [Co3(H2O)6(BBTZ)4][BW12O40]·NO3·4H2O (2) (BBTZ = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene) for the selective oxidation of alkenes to aldehydes. Compound 1 possesses a non-interpenetrated three-dimensional (3D) cds-type open framework with a 3D channel system. Compound 2 displays a 3D polyrotaxane framework with one-dimensional channels along the [100] direction. In the selective oxidation of styrene into benzaldehyde, compound 1 can achieve a 100% conversion in 4 h with 96% selectivity toward benzaldehyde, which is superior to that of compound 2. A series of control experiments reveal that the co-role of [BW12O40]5- and Co2+ active center as well as a more open framework feature co-promote the catalytic property of the POMOFs in this case. This work may suggest a new option for the development of POMOF catalysts in the selective oxidation of alkenes.

Two new hybrid compounds with chemical formulas [Co(L1)2(H2O)2]2[SiW12O40]·6H2O (1) and [Cu2(C9H22 N)2(L2)2][SiW12O40]·2H2O (2) (L1 = 3,3′-diamino-5,5′-bis(1H-1,2,4-triazole), L2 = 1,2-bis(3-(2-pyridyl)pyrazole-1-ylmethyl)benzene, C9H22 N = tripropylamine) were prepared in a hydrothermal reaction system containing Keggin-type polyoxometalates (POMs), transition metal (TM) salts (cobalt salts and copper salts), and chelate L1/L2 ligands. X-ray structural analysis reveals that 1 and 2 possess 3-D supramolecular host frameworks with large cavities and the polyoxoanions SiW12 reside in these cavities as the guest templates. The photocatalytic activities of 1 and 2 were investigated. Both compounds show efficient catalytic activity for degradation of RhB with 1 > 2. The loading amount of the POM units and the structural features of these POM-based organic-inorganic hybrid compounds may be necessary factors that affect the activity of catalysts in the photocatalytic degradation.

Two new polyoxometalate(POM)-based entangled coordination networks with chemical formula of [Mn2(H2O)2(BBPTZ)5][SiW12O40] (1) and [Ni2(H2O)2(BBPTZ)5][SiMo12O40]·6H2O (2) (BBPTZ = 4.4′-bis(1,2,4-triazol-1-ylmethyl)biphenyl), were prepared in a hydrothermal reaction system. Compounds 1–2 were characterized by elemental analyses, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. In compound 1, dangling arms thread in quadrangular window of the adjacent 2-D layers, thus resulting in a rare 2-D → 3-D polythreading motif. Compound 2 exhibits a rare 2-D → 3-D zipper-closing motif. Using the degradation of methylene blue (MB) as the model, the photocatalytic activities of compounds 1–2 were investigated. Both compounds show efficient catalytic activity for the degradation of MB with the order of 2 > 1. It is found that the POM species of compounds 1–2 play the main role in the photocatalytic degradation process.

A new cationic triazole-based metal-organic framework encapsulating Keggin-type polyoxometalates, with the molecular formula [Co(BBPTZ)3][HPMo12O40]⋅24 H2O [compound 1; BBPTZ = 4,4'-bis(1,2,4-triazol-1-ylmethyl)biphenyl] is hydrothermally synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. The structure of compound 1 contains a non-interpenetrated 3D CdSO4 (cds)-type framework with two types of channels that are interconnected with each other; straight channels that are occupied by the Keggin-type POM anions, and wavelike channels that contain lattice water molecules. The catalytic activity of compound 1 in the oxidative desulfurization reaction indicates that it is not only an effective and size-selective heterogeneous catalyst, but it also exhibits distinct structural stability in the catalytic reaction system.

Three new polyoxometalate (POM)-based metal–organic coordination networks (MOCNs) with chemical formulae of [Co(BBTZ)1.5(HBBTZ)(H2O)2][PW12O40]·H2O (1), [Co2.5(BBTZ)4(H2O)2] [BW12O40]·4H2O (2) and [Cu(BBTZ)2]5[BW12O40]2·4H2O (3) (BBTZ = 1,4-bis-(1,2,4-triazol-1-ylmethyl)benzene) were hydrothermally synthesized in a reaction system containing Keggin-type POMs, transition metal salts (cobalt salts and copper salts) and BBTZ ligands. All compounds were characterized by elemental analyses, IR, powder X-ray diffraction, TG analyses and single-crystal X-ray diffraction analyses. Compound 1 exhibits a POM-encapsulated 3-D supramolecular network, while compounds 2 and 3 display POM-supported 3-D coordination networks. Using the oxidative desulfurization of dibenzothiophene (DBT) as the model, the catalytic activities of compounds 1–3 are investigated. All three compounds show efficient catalytic activity for the oxidation of DBT with the order of 2 > 3 > 1. It is found that the POM species of compounds 1–3 play the main role in the catalytic oxidative desulfurization process, while the TM ions, the loading amounts of POMs, and the structural features of these POM-based MOCNs are also necessary factors that affect the catalytic activities. Furthermore, a surfactant-assisted hydrothermal synthesis method has been developed to prepare nanocrystal 2. SEM reveals that the as-synthesized nanocrystalline 2 is about 245 nm in diameter. The catalytic oxidative desulfurization experiments show that nanocrystal 2 possesses much higher catalytic activities than those of the large single-crystal products of 2.

Three new organic–inorganic hybrid compounds, namely [CuILp]2[W6O19]·H2O (1), [CuILp]3[W6O19]Cl (2) and [CuILp]2[W6O19]·2H2O (3) (Lp=α,α′-bis-[3-(2-pyridyl)pyrazol-1-yl]-1,4-dimethylbenzene) based on copper(I) ion, a neutral N-donor bichelate-bridging ligand (Lp) and a Lindqvist-type polyoxometalate (POM) [W6O19]2−, have been hydrothermally prepared under different synthetic conditions and structurally characterized by elemental analyses, IR spectra, TG analyses, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction analyses. Compounds 1 and 2 contain two different but topologically similar meso-helical chainlike coordination moieties. Compound 3 contains both left- and right-handed chiral “mobius strip” units. These cationic meso-helical chains and “mobius strip” units in compounds 1–3 are further combined with Lindqvist-type polyoxoanions to form 3-D supramolecular assemblies through extensive electrostatic forces and/or π–π interactions. The photo-luminescent properties of 1–3 have also been investigated, which are mainly attributed to the Lp ligand-centered emission.

The slow diffusion reactions of a double-betaine-containing ligand with YbH[SiMo12O40]·nH2O and Ca2[SiMo12O40]·nH2O led to the isolation of two new organic–inorganic hybrid assemblies, [Yb(O)(HL)2(H2L)0.5(H2O)3][SiMo12O40]·2.5CH3CN·1.5H2O (1) and [Ca(HL)2(L)0.5(H2O)4] [SiMo12O40]·5CH3CN·H2O (2) (L = 1,4-bis(pyridinil-4-carboxylato)-l,4-dimethylbenzene). Compounds 1–2 were characterized by elemental analyses, TG, IR, XPS and single-crystal X-ray diffraction. Compound 1 contains the dinuclear [(YbO)(HL)2(H2O)3]2 coordination moieties and discrete protonated L ligands, which are connected together by H-bonds and π–π interactions to form a 3D supramolecular framework with the Keggin-type [SiMo12O40]4 − polyoxoanions and solvent molecules encapsulated. Compound 2 possesses discrete [Ca(HL)2(L)0.5(H2O)4]2 coordination units that are linked by the extensive intermolecular H-bonds and π–π interactions to form a 3D supramolecular framework with the [SiMo12O40]4 − polyoxoanions and solvent molecules are encapsulated in the interbedded cavities. The structural motifs of the metal–organic coordination units can be obviously modulated by the use of chemically different cationic nodes. The degradation of Rhodamine-B (RhB) under UV irradiation with compounds 1 and 2 as heterogeneous photocatalysts were investigated, both exhibiting good photocatalytic properties. Furthermore, these hybrid compounds display luminescent properties induced by organic ligands.

Investigation into a hydrothermal reaction system with transition-metal (TM) ions, 1,4-bis(1,2,4-triazol-1-lmethyl)benzene (BBTZ) and various charge-tunable Keggin-type polyoxometalates (POMs) led to the preparation of four new entangled coordination networks, [Co(II) (HBBTZ)(BBTZ)2.5 ][PMo12 O40 ] (1), [Cu(I) (BBTZ)]5 [BW12 O40 ]⋅H2 O (2), [Cu(II) (BBTZ)]3 [AsW(V) 3 W(VI) 9 O40 ]⋅10 H2 O (3), and [Cu(II) 5 (BBTZ)7 (H2 O)6 ][P2 W22 Cu2 O77 (OH)2 ]⋅6 H2 O (4). All compounds were characterized by using elemental analysis, IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. The mixed valence of W centers in compound 3 was further confirmed by using XPS spectroscopy and bond-valence sum calculations. In the structural analysis, the entangled networks of 1-4 demonstrate zipper-closing packing, 3D polythreading, 3D polycatenation, and 3D self-penetration, respectively. Moreover, with the enhancement of POM negative charges and the use of different TM types, the number of nodes in the coordination networks of 1-4 increased and the basic metal-organic building motifs changed from a 1D zipper-type chain (in 1) to a 2D pseudorotaxane layer (in 2) to a 3D diamond-like framework (in 3) and finally to a 3D self-penetrating framework (in 4). The photocatalytic properties of compounds 1-4 for the degradation of methylene blue under UV light were also investigated; all compounds showed good catalytic activity and the photocatalytic activity order of Keggin-type species was initially found to be {XMo12 O40 }{XW12 O40 }{XW12-n TMn O40 }.

The heptamolybdate [NH4]6[Mo7O24], as a common polyoxometalate (POM) precursor with dynamic configuration transformation in aqueous solution by changing the pH, has been introduced into the hydrothermal reaction system containing copper ions and bichelate-bridging ligands, leading to the isolation of seven new organic–inorganic hybrid compounds [CuI2Lo2][Mo6O19] (1), [CuII2Lo2][β-Mo8O26]·2H2O (2), [CuII4Lo2(pypz)4][α-Mo8O26]·3H2O (3), [CuII4Lp4(H2O)4][α-Mo8O26][β-Mo8O26]·4H2O (4), [CuI4Lp3][β-Mo8O26]·H2O (5), [CuI4Lp4][α-Mo8O26] (6), and [CuI2Lp2(Emim)2][β-Mo8O26] (7) (bis(3-(2-pyridyl)pyrazole-1-ylmethyl)benzene = bppmb, Lo = 1,2-bppmb, Lp = 1,4-bppmb, pypz = 3-(2-pyridyl)pyrazole, Emim = 1-ethyl-3-methylimidazolium). All compounds were characterized by elemental analysis, IR spectroscopy, TG analysis, powder X-ray diffraction and single-crystal X-ray diffraction analysis. The structural analyses show that the isopolymolybdate clusters act as a type of “molecular adaptor”, which modulate the coordination mode of metal–organic subunits, leading to a series of new metal–organic secondary building units, such as the “Mobius-Ring”-type binuclear unit, “S”-type binuclear unit, butterfly-type unit, helical chain and mesomeric helical chain. As a result, the POM anions and the metal–organic subunits have suitable matching modes to form new hybrid self-assemblies. The photocatalytic properties of compounds 1–7 for the degradation of Rhodamine-B (RhB) under UV irradiation were investigated. All compounds showed good catalytic activity. Furthermore, the luminescent properties of compounds 1–7 have also been explored, indicating an organic ligand-based emission mode for all compounds.

A new organic–inorganic hybrid compound (NH4)2[{Mn(salen)(H2O)}6V6O18](NO3)2·30H2O (salen2− = N,N′-(ethylene)bis(salicylideneiminate)) (1) was synthesized by the reaction between NH4VO3 and [Mn(salen)(H2O)2]ClO4 in a methanol–water solution with pH = 5.0 adjusted by nitric acid. Compound 1 was characterized by elemental analyses, TG, IR, UV–vis, XPS and the single-crystal X-ray diffraction. Compound 1 possesses a discrete cyclic hexanuclear vanadates, which is unprecedentedly grafted by six [Mn(salen)(H2O)2] units. Such a new hybrid compound displays good UV photocatalytic activity for RhB degradation.

The reaction between a double-betaine-containing ligand and DyH[PMo11VO40]·nH2O led to a new polyoxometalate-based lanthanide-organic hybrid compound with the molecular formula [Dy(HL)(L)1.5(H2O)3][PMo11VO40]·8H2O (1) (L = 1,4-bis(pyridinil-4-carboxylato)-l,4-dimethylbenzene). Compound 1 was characterized by elemental analyses, TG, IR, XPS and the single-crystal X-ray diffraction. Compound 1 possesses a cationic 1D polymeric chain [Dy(HL)(L)1.5(H2O)3]n4n+ with cyclic-, chain- and semi-cyclic-like fragments, corresponding to three different configurations of the double-betaine-containing ligand. These 1D chains are connected together by the H-bonds and π–π interactions to form a 3D supramolecular framework, encapsulating the vanadium-substituted Keggin-type polyoxoanions [PMo11VO40]4−and the solvent molecules. This composite compound displays electrocatalytic activities towards the reduction of nitrite and the luminescent property.

A triple-wavelength overlapping resonance Rayleigh scattering (TWO-RRS) method was developed to detect dextran sulfate sodium (DSS) with crystal violet (CV). At pH 10.0 Britton Robinson buffer solution medium, the interaction of CV with DSS occurred which greatly enhanced the RRS intensity with the new RRS peaks appearing at 340, 501 and 671 nm and all these three peaks enhanced with the increase of DSS concentration in the range of 0.04-2.5 microg ml(-1) and the detection limit for the three single peaks was 0.024, 0.027, and 0.027 microg ml(-1), respectively, whereas that of the TWO-RRS method was 0.013 microg ml(-1). The TWO-RRS method was found to have much better flexibility and high sensitivity than the single-wavelength method. In this paper, the interaction conditions were optimized. The affecting factors and characteristics of RRS for the interaction of DSS with CV were investigated and a sensitive method for the determination of trace amounts of DSS using the TWO-RRS method was developed.

The introduction of an extended bridging bis(triazole) ligand, that is, 4,4′-bis(1,2,4-triazol-1- ylmethyl)biphenyl (BBPTZ), into the hydrothermal reaction system containing transition metal ions and Keggin-type polyoxometalates (POMs) led to the isolation of three new organic–inorganic hybrid entangled coordination networks, [CuI2CuII(BBPTZ)6][SiW12O40]⋅12 H2O (1), [Ni(BBPTZ)2(H2O)][H2SiW12O40]⋅11 H2O (2), and [Ni2(BBPTZ)4(H2O)2][SiW12O40]⋅3 H2O (3). All three compounds were characterized by elemental analysis, IR spectroscopy, TG analysis, powder X-ray diffraction, and single-crystal X-ray diffraction. Compound 1 contains a 2-D POM-based metal–organic layer entangled with 1-D ladder-like metal–organic chains. The adjacent 2-D networks are parallel to each other, further stacking into a 3-D supramolecular framework with 1-D channels. Compound 2 exhibits a 1-D cantilever-type loop-containing chain. The Keggin-type POMs act as the cantilever groups, leading to the adjacent catilever-type chains interwaving together to form a 3-D supramolecular open framework with two types of channels. Compound 3 possesses a 3-D open framework based on 2-D metal–organic undulated layer and Keggin-type POM clusters. Three sets of such frameworks further interpenetrate with each other to form an interesting three-fold interpenetrating framework. The photocatalytic activities of compounds 1–3 for the decomposition of methylene blue (MB) under UV light have been investigated.

The reaction of a double-betaine-containing ligand with LnPMo(12)O(40)·nH(2)O (Ln = Dy, Tb and Er) led to the isolation of new polyoxometalate-templated lanthanide-organic hybrid layers with the molecular formula [Ln(L)(1.5)(H(2)O)(5)][PMo(12)O(40)]·1.5CH(3)CN·2H(2)O (Ln = Dy (1), Tb (2) and Er (3); L = 1,4-bis(pyridinil-4-carboxylato)-l,4-dimethylbenzene). All compounds were characterized by elemental analyses, TG analyses, IR and the single-crystal X-ray diffraction. Compounds 1-3 are isostructural and possess a 2D undulating cationic network [Ln(L)(1.5)(H(2)O)(5)](n)(3n+) with the honeycomb-like cavities. Interestingly, the interval 2D networks are further connected by the H-bonds to form a 3D supramolecular framework. Moreover, two of such identical supramolecular frameworks are 2-fold interpenetrated with each other and encapsulate the α-Keggin-type [PMo(12)O(40)](3-) anionic templates and the solvent molecules. These composite compounds display both luminescent properties (induced by organic ligands and/or lanthanide ions) and electrocatalytic activities towards the reduction of nitrite.

Three new organic–inorganic hybrid compounds based on copper-bis(triazole) complexes and Keggin-type polyoxometalates (POMs) with different negative charges, [Cu(I)BBTZ]3[PMo12O40] (1), [Cu(I)BBTZ][Cu(I)(HBBTZ)2][SiMo12O40]·2.5H2O (2) and [Cu(I)BBTZ]6[SiWV2WVI10O40]·2H2O (3) (BBTZ = 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene), have been hydrothermally prepared and characterized by elemental analyses, IR spectra, TG analyses, XPS spectra, powder X-ray diffraction and single-crystal X-ray diffraction analyses. Compounds 1 and 2 exhibit the POM-templated 3D host–guest supramolecular frameworks. Compound 3 displays a POM-supported 3D open framework. In these three hybrid compounds, the structural transformation from host–guest framework to open framework were modulated by the introduction of Keggin-type polyoxoanions with different negative charges. Moreover, the electrochemical properties of compounds 1–3 were investigated and all these compounds show the electrocatalytic activities towards the reduction of nitrite.