To systematically explore the effect of polynuclear complexes on photocatalytic degradation of the organic dyes, a series of coordination complexes containing CdII clusters, formulated as {[Cd3L2(H2O)5]·H2O} n (1), {[Cd3L2(hbmb)(H2O)2]·2.5H2O} n (2), {[Cd3L2(btbb)(H2O)2]·2EtOH·1.5H2O} n (3), and {[Cd6L4(bipy)2(H2O)6]·3H2O} n (4) (H3L = 3,4-bi(4-carboxyphenyl)-benzoic acid, hbmb = 1,1′-(1,6-hexane)bis(2-methylbenzimidazole), btbb = 1,4-bis(2-(4-thiazolyl)benzimidazole-1-ylmethyl)benzene, 4,4′-bipy = 4,4′-bipyridine), have been designed and synthesized. Complex 1 based on trinuclear CdII clusters exhibits a new (3,3,6)-connected 3D framework. 2 belongs to a (3,3,8,8)-connected tfz-d topology net with pillar-layered frameworks assembled by two kinds of trinuclear CdII clusters. 3 is a 3D pillar-layered framework, which features a (3,8)-connected tfz-d net based upon one kind of trinuclear CdII cluster. 4 presents a new 3D (3,6,10)-connected framework with dinuclear and tetranuclear clusters. The photocatalytic properties of complexes 1–4 have been studied in detail. Remarkably, 1–4 all reveal good photocatalytic activity in MB/MO degradation. The optical energy gap calculated by the diffuse reflectivity spectra of 1–4 are consistent with their degradation rates. Moreover, the experimental results further demonstrate that the cluster complexes containing different kinds of nuclei may exert different impact on the decomposition of disparate organic dyes.

It remains an unresolved challenge to achieve spatial and temporal monitoring of drug release from nanomedicines (NMs) in vivo, which is of crucial importance in disease treatment. To tackle this issue, we constructed core− satellite ICG/DOX@Gel-CuS NMs, which consist of gelatin (Gel) nanoparticles (NPs) with payloads of near-infrared fluorochrome indocyanine green (ICG) and chemo-drug doxorubicin (DOX) and surrounding CuS NPs. The fluorescence of ICG was initially shielded by satellite CuS NPs within the intact ICG/DOX@Gel-CuS NMs and increased in proportion to the amount of DOX released from NMs in response to enzyme-activated NMs degradation. For more comprehensive understanding of the drug-release profile, a theoretical model derived from computer simulation was employed to reconstruct the enzyme-activatable drug release of the ICG/DOX@Gel-CuS NMs, which demonstrated the underlying kinetics functional relationship between the released DOX amount and recovered ICG fluorescence intensity. The kinetics of drug release in vivo was assessed by administrating ICG/DOX@Gel-CuS NMs both locally and systemically into MDA-MB-231 tumor-bearing mice. Upon accumulation of ICG/DOX@Gel-CuS NMs in the tumor, overexpressed enzymes triggered the degradation of the gelatin scaffold as well as the release of DOX and ICG, which can be visually depicted with the ICG fluorescence signal increasing only in the tumor area by fluorescence imaging. Additionally, the photoacoustic signal from CuS NPs was independent from the physical status of ICG/DOX@Gel-CuS NMs and hence was utilized for real-time NMs tracking. Thus, by taking advantage of the core−satellite architecture and NMs degradability in tumor site, the DOX release profile of ICG/DOX@Gel-CuS NMs was monitored by fluorescence and photoacoustic dual-modal imaging in a real-time noninvasive manner.

To explore new 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY)-derived metal-organic frameworks (MOFs), we employed 2,6-dicarboxyl-1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroboradiazaindacene (H2L) as a ligand to successfully synthesize five coordination polymers, namely, {[Zn2(L)2(bpp)]·2H2O·2EtOH}n (1), {[Cd2(L)2(bpp)]·2H2O·EtOH}n (2), {[Cd2(L)(bpe)3(NO3)2]·2H2O·DMF·EtOH}n (3), {[Cd(L)(bpe)0.5(DMF)(H2O)]}n (4), and {[Cd(L)(bpe)0.5]·1.5H2O·DMF}n (5) (bpp = 1,3-bi(4-pyridyl)propane, bpe = 1,2-bi(4-pyridyl)ethane). Except for two 2D-layer coordination polymers 3 and 4, the rest samples exhibit 3D metal-organic frameworks with certain pore sizes, especially MOFs 1 and 5. Spectroscopic and crystallographic investigations demonstrate that the absorption and emission energies of the BODIPY chromophores are sensitive to the coordination modes. Moreover, in case 2, the transition metal centers coordinated with the dicarboxylate ligands L(2-) are capable of forming the two BODIPY units in coplanar arrangements (θ = 37.9°), simultaneously suppressing the uncommon J-dimer absorption band centered at 705 nm with a long tail into the near-infrared region at room temperature. On the other hand, in comparison with the ligand H2L, the emission of monomer-like BODIPY in case 3 is enhanced in the solid state by a considerably long distance between the parallel BODIPY planes (about 14.0 Å).

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Six fascinating coordination polymers (CPs) showed good photocatalytic activities for the degradation of methylene blue (MB).

Summary As the most abundant and genetically diverse biological entities, viruses significantly influence ecological, biogeographical and evolutionary processes in the ocean. However, the biogeography of marine viruses and the drivers shaping viral community are unclear. Here, the biogeographic patterns of T4‐like viruses and the relative impacts of deterministic (environmental selection) and dispersal (spatial distance) processes were investigated in the northern South China Sea. The dominant viral operational taxonomic units were affiliated with previously defined Marine, Estuary, Lake and Paddy Groups. A clear viral biogeographic pattern was observed along the environmental gradient from the estuary to open sea. Marine Groups I and IV had a wide geographical distribution, whereas Marine Groups II, III and V were abundant in lower‐salinity continental or eutrophic environments. A significant distance‐decay pattern was noted for the T4‐like viral community, especially for those infecting cyanobacteria. Both deterministic and dispersal processes influenced viral community assembly, although environmental selection (e.g. temperature, salinity, bacterial abundance and community, etc.) had a greater impact than spatial distance. Network analysis confirmed the strong association between viral and bacterial community composition, and suggested a diverse ecological relationship (e.g. lysis, co‐infection or mutualistic) between and within viruses and their potential bacterial hosts.

A series of novel Cd(II) coordination complexes, formulated as {[Cd(btbb)0.5(p-phda)]·H2O}n (), [Cd(btbb)0.5(oba)]n (), {[Cd2(btbb)(m-bdc)2(H2O)]·2H2O}n (), {[Cd(btbb)0.5(btec)0.5(H2O)]·2H2O}n (), [Cd(btbb)0.5(o-bdc)]n () and {[Cd2(btbb)(bptc)(H2O)]·4H2O}n () (btbb = 1,4-bis(2-(4-thiazolyl)benzimidazol-1-ylmethyl)benzene, H2phda = phenylenediacetic acid, H2oba = 4,4'-oxybis(benzoic acid), m-H2bdc = 1,3-benzenedicarboxylic acid, H4btec = 1,2,4,5-benzenetetracarboxylate, o-H2bdc = 1,2-benzenedicarboxylic acid, H4bptc = 3,3',4,4'-benzophenone tetracarboxylic acid), have been obtained by solvothermal/hydrothermal reactions for the exploration of efficient photocatalytic degradation of organic dye pollutants. Complex features a 6-connected 3D pcu α-Po primitive cubic topology net with the point symbol 4(12)·6(3). Interestingly, complexes , and contain left- and right-handed helical chains (: a 2-fold interpenetrating 3D architecture with {4(12)·6(3)}-pcu topology network; : a (3,6)-connected net with a vertex symbol (4(2)·5(4)·6(6)·7·8(2))(4·6(2)); : a (3,4)-connected 3,4L83 topology net with point symbol (4(2)·6)(4(2)·6(3)·8)). Complex exhibits a (3,4)-connected 3,4T48 topology net with point symbol (8(4)·10(2))(8·10(2)), while complex possesses a (3,5)-connected 3,5L2 topology with the point symbol (4(2)·6)(4(2)·6(7)·8). Furthermore, the photophysical studies indicate that the relatively narrow optical energy gaps of complexes (<2.30 eV) calculated from the diffuse reflectivity spectra reflect their outstanding semiconductive nature. The photocatalytic properties of complexes were studied in detail, and the results demonstrate their good photocatalytic activities in methylene blue (MB) degradation reactions, especially for complexes , and (: 91.4%, : 92.7%, : 86.7%).

In our continuing quest to develop a metal-organic framework (MOF)-catalyzed tandem pyrrole acylation-Nazarov cyclization reaction with α,β-unsaturated carboxylic acids for the synthesis of cyclopentenone[b]pyrroles, which are key intermediates in the synthesis of natural product (±)-roseophilin, a series of template-induced Zn-based (1-3) metal-organic frameworks (MOFs) have been solvothermally synthesized and characterized. Structural conversions from non-porous MOF 1 to porous MOF 2, and back to non-porous MOF 3 arising from the different concentrations of template guest have been observed. The anion-π interactions between the template guests and ligands could affect the configuration of ligands and further tailor the frameworks of 1-3. Futhermore, MOFs 1-3 have shown to be effective heterogeneous catalysts for the tandem acylation-Nazarov cyclization reaction. In particular, the unique structural features of 2, including accessible catalytic sites and suitable channel size and shape, endow 2 with all of the desired features for the MOF-catalyzed tandem acylation-Nazarov cyclization reaction, including heterogeneous catalyst, high catalytic activity, robustness, and excellent selectivity. A plausible mechanism for the catalytic reaction has been proposed and the structure-reactivity relationship has been further clarified. Making use of 2 as a heterogeneous catalyst for the reaction could greatly increase the yield of total synthesis of (±)-roseophilin.