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A new surface imprinting technique was reported to synthesize multi-walled carbon nanotubes-molecularly imprinted polymers (MWNTs-MIPs) using erythromycin as the template, acryloyl-β-cyclodextrin (acryloyl-β-CD) and methacrylic acid (MAA) as the binary functional monomers. The MWNTs-MIPs were characterized by transmission electron microscopy (TEM), scanning electron micrograph (SEM) and Fourier transform-infrared spectroscopy (FT-IR). Adsorption experiments indicated the MWNTs-MIPs prepared with acryloyl-β-CD and MAA have high selective for erythromycin. The feasibility of the MWNTs-MIPs as solid-phase extraction (SPE) sorbent was evaluated, and the results showed that it can selectively extract erythromycin from chicken muscle samples with the recoveries ranging from 85.3% to 95.8%. The molecularly imprinted solid-phase extraction (MISPE) method could be applied for preconcentration and purification of erythromycin from chicken muscle samples.

The complete sequences of the mitochondrial DNA genome from Garrulax perspicillatus was determined by 21 pairs of primers using the polymerase chain reaction method. The genome (17,873 bp in length) contained 37 genes (2 rRNA genes, 22 tRNA genes and 13 protein-coding genes) 2 control regions (CR) at two different locations of mitogenome. All the protein-coding genes in G. perspicillatus were distributed on the H-strand, except for the ND6 subunit gene and eight tRNA genes which were encoded on the L-strand.

The grey-backed thrush (Turdus hortulorum) is an endangered bird species, which is mainly distributed in northern China, Korean Peninsula and Vietnam. In this study, the complete nucleotide sequence of the mitochondrial genome of T. hortulorum is determined. The circle genome was 16,759 bp in length and consisted of 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes and 1 control region (D-loop). The mtDNA of T. hortulorum is similar to the typical mtDNA of birds and other vertebrates.

The complete sequence of the mitochondrial DNA genome from Garrulax cineraceus was determined using the polymerase chain reaction method. The genome (17,800 bp in length) contained 37 genes (13 protein-coding genes, 2 rRNA genes and 22 tRNA genes) and 2 control regions (D-loop) at two different locations of mitogenome, which is similar to the typical mtDNA of vertebrates. All the protein-coding genes in G. cineraceus were distributed on the H-strand, except for the ND6 subunit gene and eight tRNA genes which were encoded on the L-strand.

A sensitive and selective electrochemical sensor based on a polyaniline modified carbon electrode for the determination of L-phenylalanine has been proposed by utilizing β-cyclodextrin (β-CD) incorporated multi-walled carbon nanotube (MWNT) and imprinted sol-gel film. The electrochemical behavior of the sensor towards L-phenylalanine was investigated by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and amperometric i-t curve. The surface morphologies of layer-by-layer assembly electrodes were displayed by scanning electron microscope (SEM). The response mechanism of the imprinted sensor for L-phenylalanine was based on the inclusion interaction of β-CD and molecular recognition capacity of the imprinted film for L-phenylalanine. A linear calibration plot was obtained covering the concentration range from 5.0 × 10(-7) to 1.0 × 10(-4) mol L(-1) with a detection limit of 1.0 × 10(-9) mol L(-1). With excellent sensitivity, selectivity, stability, reproducibility and recovery, the electrochemical imprinted sensor was used to detect L-phenylalanine in blood plasma samples successfully.

A core-shell complex-imprinted polymer (CIP) was synthesized and evaluated for selective extraction of melamine from dairy products. The CIP synthesis based on surface modification of home-made silicon microspheres was conducted via a metal complex as functional monomer, ethylene glycol dimethylacrylate as cross-link and melamine as template. The resulting CIP was characterized by SEM and Fourier transform infrared spectroscopy. When the amount of silica microspheres was 100 mg and the molar ratio of copper(II) methacrylate to EDGMA was 1:10, well-dispersed particles were obtained. The complex-imprinted SPE condition was optimized and the maximum enrichment factor of melamine can be up to 40. The reliability of complex-imprinted SPE for extraction and enrichment of melamine was investigated and proved by using spiked samples including milk and milk powder with the recoveries ranging from 87 to 92%.

A novel sensitive and selective imprinted electrochemical sensor was successfully constructed for the direct detection of l -histidine by combination of a molecular imprinting film and multi-walled carbon nanotubes (MWNTs). The sensor was fabricated onto an indium tin oxide (ITO) electrode via stepwise modification of MWNTs and a thin film of molecularly imprinted polymers (MIPs) via sol–gel technology. The introduced MWNTs exhibited noticeable enhancement on the sensitivity of the MIPs sensor. Meanwhile, the molecularly imprinted film displayed high sensitivity and excellent selectivity for the target molecule l -histidine. The proposed imprinted sensor was characterized by using scanning electron microscope (SEM) and electrochemical methods involving cyclic voltammetry (CV), differential pulse voltammetry (DPV) and amperometric i–t curve. A linear ranging from 2.0 μmol L−1 to 1.0 mmol L−1 for the detection of l -histidine was observed with the detection limit of 5.8 × 10−9 mol L−1 for S/N = 3. This imprinted electrochemical sensor was successfully employed to detect l -histidine in human blood serum.

The rapid development in inorganic–organic hybrid frameworks has enabled the discovery of many structurally fascinating and technologically useful materials. The design of such hybrid crystals with noncentrosymmetric frameworks is particularly important because of their interesting electronic and optical properties. Several synthetic approaches, including the use of chiral and unsymmetric ligands, or spontaneous resolution via using achiral building blocks, have been applied to facilitate the formation of acentric and chiral hybrid materials. In this highlight, we will review another way to increase the chance of obtaining acentric and chiral frameworks by adding alkali or alkaline earth metals into heterometallic systems. The synthesis of these frameworks is discussed along with their potential NLO properties.

Two Cu(I) coordination polymers based on the in situ generated 1-(4-tetrazolephenyl)imidazole ligand show intriguing ABW and (4,8)-connected topologies, and both of them are promising luminescent materials for sensing of nitrobenzene.

By varying the stoichiometric ratio of Eu3+, Tb3+ and Gd3+ ions in a lanthanide metal–organic framework, a mixed-Ln MOF, [Eu0.0040Tb0.0460Gd0.9500(BTB)(DMSO)2]·H2O, has been designed to display white-light emission. In addition, the switch between blue, white, and yellow for this material has been achieved by controlling the energy transfer process.

Pseudo-achiral metal-centre driven spontaneous resolution occurred simultaneously in the formation of two Δ- and Λ-isomers of [CdBa(OBA)2(DMF)(CH3OH)(H2O)]·H2O (H2OBA = 4,4′-oxybis(benzoic acid)), which illustrated a clear relationship between chirality and helicity: the absolute sense of a double-helix made of achiral components is induced by metal centres in the two enantiomeric forms.

The structure of the title compound, C8H15NO2, is normal and contains a six-membered ring with a chair conformation. The crystal structure is stabilized by inter­molecular N—H⋯O hydrogen bonds.

Two classical metal clusters, CuI4I4 and CuI6S6, are introduced as functional connecting nodes to construct a novel multi-metal-cluster MOF [(CuI4I4)3(CuI6)2(3-ptt)12]n·24nDEF·12nH2O (1) that incorporate their inherent luminescent properties, induced by their respective metal–metal interactions. These two distinct clusters are combined together for the first time to perform as functional luminophores that display unusual dual emission with both thermochromic luminescence and near-infrared (NIR) character.

The first example of an inorganic-organic composite framework with a 3D inorganic Cd-O-M (M = Cd, Rb) connectivity, featuring a unique {Cd(7)Rb}(n) helix and nanoscale {Cd(16)Rb(4)} and {Cd(18)Rb(2)} rings, has been constructed and structurally characterized. This compound exhibits white-light emission and a wavelength-dependent photochromic response.

An unusual highly connected 3D framework, [K2Cd3(OBA)4(H2O)2(DMF)2](H2O)2 (1) that contains three windows along separate dimensions, has been constructed from a flexible V-shaped ligand 4,4′-oxydibenzoic acid (H2OBA) and a infinite linear {K2Cd3(COO)8}n cluster under solvothermal conditions. Owing to the existence of a polar Ccarboxyl–Ocore–Ccarboxyl moiety in the ligand and the coordinated hydrophilic DMF molecule, a hydrophilic environment is generated at the pore surface. Compound 1 shows high adsorption capacity for polar molecules, such as methanol (7.83%), ethanol (7.13%) and water (13.37%), but exhibits very low uptake capacity for non-polar molecules like methane (0.49%) and cyclohexane (0.68%). Furthermore, its luminescent properties including the quantum yield and lifetime value have also been investigated.

Two enantiomorphic 3D Zn(II)–carboxylate metal–organic frameworks [Zn(bpydc)(H2O)2] (1M and 1P) (H2bpydc = 2,2′-bipyridyl-5,5′-dicarboxylic acid) have been synthesized. They both contain an elegant double helix, self-organized through hydrogen bonds between the coordinated water molecules and uncoordinated carboxylate oxygen atoms. This double helical structure serves as a chiral source which transmits chiral information over the whole 3D framework.

New luminescent lanthanide-carboxylate frameworks, formulated as [Ln4(m-BDC)6(H2O)4(DMF)]·(H2O)2·(DMF) (Ln = Eu 1; Gd 2; Tb 3) (m-H2BDC = 1,3-benzenedicarboxylic acid) have been solvo(hydro)thermally synthesized. Single-crystal X-ray diffraction studies reveal that compounds 1–3 are isomorphous and each displays a layered structure constructed by helical lanthanide-carboxylate chains. DFT and TD-DFT calculations were conducted in detail to discuss the energy levels, including the HOMO, LUMO, singlet and triplet energies of the m-H2BDC ligand. The results indicate that the m-BDC2− dianion acts as an antenna chromophore that is able to efficiently absorb and transfer energy to the lanthanide ions. Compounds 1–3 all exhibit high thermostability and are stable up to 450 °C, as confirmed by the TGA and temperature-dependent PXRD experiments. Compounds 1 and 3 are strong luminescent materials. Compound 3 is among some of the best examples of luminescent lanthanide compounds, with highly efficient emission quantum yields of 81.40% at 77 K, 75.37% at room temperature and 56.64% after calcination at 450 °C, respectively. In addition, the energy transfer processes for compounds 1 and 3 have also been studied and illustrated in detail.

Through the in situ decomposition of DMSO (dimethyl sulfoxide), heterometallic inorganic frameworks, formulated as [KLn(SO4)2H2O] (Ln = Sm 1, Eu 2, Gd 3, Tb 4, Dy 5, Ho 6, Er 7) were synthesized under the help of facile and effective one-pot solvothermal reactions. These in situ reactions enhanced the reactivity and coordination ability of the sulfate anions, leading to the formation of new 3D lanthanum sulfate frameworks with optical and magnetic properties. Compounds 2 and 4 are strong luminescent materials which display characteristic Eu3+ and Tb3+ emission bands in the visible region with high quantum yields and long luminescent lifetimes. Variable-temperature magnetic susceptibility studies revealed that 3 and 5–7 show anti-ferromagnetic behaviors. Their thermal stability, demonstrated from the TGA profiles and temperature dependent XRD measurements, is among the highest of reported lanthanum sulfate frameworks. Additionally, the band structure calculations for 3, and 7, based on the density functional theory methods, were also performed.

A novel tetradecanuclear mixed-valent cobalt cluster, formulated as [Co(II)(10)Co(III)(4)(OH)(2)O(6)(hmp)(10)(pdm)(4)(CH(3)OH)(2)]·5H(2)O (1), was obtained using mixed ligands of 2-(hydroxymethyl)pyridine (hmpH) and 2,6-pyridinedimethanol (pdmH(2)). The cobalt ions in 1 are connected by ten chelating hmp(-) ligands, four tris-chelating pdm(2-) ligands and six μ(3)-oxide/hydroxide anions, forming a unique shield-like planar structure that is rarely observed for Co-based clusters. Compound 1 displays slight frequency dependence at static zero field below 4.5 K, suggesting that it might be a single molecule magnet (SMM).