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Abstract: Although PEGylation is a potential approach to prolong the half-lives and reduce the dosing frequency of therapeutic proteins, conjugation behaviors of polymer have pivotal effects on the remaining bioactivities of the derivatives. In this study, the PEGylation strategy of recombinant human interleukin-1 receptor antagonist was investigated. The random conjugation of polyethylene glycol to amino groups on the protein resulted in a severe loss of activity and only retained 9.8% of the activity. In contrast, the PEGylation at the thiol groups had moderate effects on the bioactivity of protein and 40% of activity was conserved. The results suggested that the thiol-target PEGylation was more beneficial for IL-1ra. [Copyright &y& Elsevier]

Abstract: Human serum albumin (HSA) and bovine hemoglobin (Hb) conjugate is a promising candidate as a blood substitute. However, preparation of the conjugate is problematic because both proteins tend to conjugate between themselves rather than crosslink each other. In this work, a facile process for conjugation of Hb and HSA was developed through control strategy of the reaction. The reaction was carried out in a buffer containing borax-borate and mannite. The borax-borate was used for pH buffering while mannite was used as a pH switch and a reaction promoter. As a result, self-conjugation of Hb and self-conjugation of HSA were minimized. After the one-step conjugation reaction in aqueous solution, followed by the one-step purification by ion-exchange chromatography, the conjugate of HSA and Hb was obtained with the total yield about 50%. The P 50 and the Hill coefficient for the product were 16.1mmHg and 1.82, respectively. [Copyright &y& Elsevier]

One novel cyanide-bridged mixed-valence {FeIII 2 (μ -CN) 4 FeII 2 } square cluster exhibits thermally-induced, reversible, complete spin transition behaviour at two out of four metal centers. • One novel cyano-bridged mixed-valence bimetallic {FeIII 2 (μ -CN) 4 FeII 2 } cluster has been prepared. • The square cluster exhibits thermally-induced, reversible, complete spin transition behavior. One novel cyano-bridged mixed-valence bimetallic {FeIII 2 (μ -CN) 4 FeII 2 } cluster, {[(Tp)FeIII(CN) 3 ] 2 [FeII(Py 2 N 2)] 2 }·(PF 6) 2 (1), has been synthesized (Tp = hydrotris(pyrazolyl)borate, Py 2 N 2 = N,N'-bis(2-pyridylmethyl)-N,N'-bis(4-benzyl)-1,2-ethanediamine). The molecular structure has been determined by single-crystal X-ray diffraction. Compound 1 exhibit temperature driven Fe(II) spin crossover behaviour (SCO) associated with the high-spin (HS) ↔ low-spin (LS) transition with the transition temperature of 130 K at two out of four metal centers. The evolution of HS and LS Fe(II) ions with temperature was followed by FT-IR, X-ray crystallography, the variable temperature magnetic susceptibility. [ABSTRACT FROM AUTHOR]

Highlights: [•] Preparation of europium (III) ternary complexes with β-diketone and nitrogen heterocyclic ligands. [•] Photoluminescence behavior of europium (III) ternary complexes. [•] Analysis of the Judd–Ofelt intensity parameters (Ωt ), the lifetime (τ) and the luminescent quantum yield (η). [Copyright &y& Elsevier]

Three new CdII coordination polymers (CPs) based on a new flexible large π-electron-rich bis(pyridinyl-imidazole) ligand 9,10-bis((2-(pyridin-2-yl)-1 H -imidazole-1-yl)methyl)anthracene (bpima) have been synthesized under solvothermal conditions using a mixed-ligand strategy: {[Cd(bpima) 0.5 (nda)(H 2 O)]·DMF} (CP 1), {[Cd(bpima) 0.5 (oba)]·DMF·2H 2 O} (CP 2), {[Cd(bpima) 0.5 (ipa)(H 2 O)]·DMF·2H 2 O} (CP 3), (H 2 nda = naphthalene-1,4-dicarboxylic acid; H 2 oba = 4,4′-oxydibenzoic acid and H 2 ipa = 5-(tert -butyl)isophthalic acid). CP 1 and CP 2 both feature 2D layer structures with hcb and sql topology, respectively. CP 3 shows 1D ladder-like double-chain structure. In additional, luminescent properties of CP 1 and CP 3 have been systematically investigated and demonstrated multi-responsive luminescent sensitivities. Two compounds can be used for detection of Cr 2 O 7 2− and 2,4,6-trinitrophenol (TNP) with high sensitivity (High quenching efficiency K sv : for Cr 2 O 7 2−: 5.07 × 104 M−1 for CP 1 and 7.38 × 104 M−1 for CP 2 ; for TNP: 4.87 × 104 M−1 for CP 1 and 5.13 × 104 M−1 for CP 2. low detection limit values: for Cr 2 O 7 2−: 0.56 μM for CP 1 and 0.38 μM for CP 2 ; for TNP: 0.63 μM for CP 1 and 0.52 μM for CP 2) and as well as good recyclability. In addition, the sensing mechanism for Cr 2 O 7 2− and TNP is also discussed by experimental studies and theory calculations, which was attributed to the co-existence of competitive absorption (CA), fluorescence resonance energy transfer (FRET) and photoinduced electron transfer (PET) progress for TNP and CA progress for Cr 2 O 7 2−, respectively. Moreover, simple fluorescent filter paper based on CP 1 has been developed to achieve detection of Cr 2 O 7 2− and TNP via the unaided eye, which has great potential for practical applications. • Three new anthracene-based CdII-CPs with different structures were synthesized. • Two CPs both possess high sensitive detectability in sensing Cr 2 O 7 2− and TNP in water. • CA, PET and FRET progress contributed to luminescence quenching processes. [ABSTRACT FROM AUTHOR]

The preparation of high lignin content hydrogels with good mechanical and multifunctional properties remains a huge challenge. In this study, a novel polymer-nanoparticle hydrogel was developed by a covalent crosslinking strategy, which not only preserved the characteristics of nanoparticles but also gives them good mechanical properties. Herein, lignin-silver nanoparticles (Lig-Ag NPs) were prepared from industrial lignin starting material and crosslinked into hydrogel with poly(ethylene glycol) diglycidyl ether. The obtained hydrogel (Lig-Ag NPs/PEG, LANP) exhibited good mechanical properties (elongation at break 53%, tensile strength 94.67 kPa, toughness 277.32 kJ m−3), adhesiveness, conductivity, pressure- and pH-stimuli-responsiveness, which benefited from the appropriate degree of crosslink, the generated catechol groups and redox-active quinone/semiquinone free radicals from Lig-Ag NPs. These functional properties can also be tuned by the contents of Lig-Ag NPs. Based on the above properties, a LANP sensor was assembled and showed good application for pressure- and pH-monitoring. This work provides a green and facile strategy of lignin valorization towards new multi-functional and smart applications. • Lignin-silver nanoparticles/PEG hydrogel (LANP) was fabricated by covalent bonds. • The mechanical properties of LANP can be tuned and improved by Lig-Ag NPs. • LANP has good adhesiveness, pressure sensitivity, and pH-stimuli-responsiveness. • LANP showed good application for pressure- and pH-monitoring. [ABSTRACT FROM AUTHOR]

Abstract: Inulin, a plant-source polysaccharide, was cross-linked and evaluated as a new potential plasma expander in vitro and in vivo. The cross-linked inulin (CLI) in three different molecular sizes (54, 100 and 146kDa) was characterized by gel filtration chromatography coupled with multi-angle laser light scattering. Their in vivo physiological properties, including blood pressure and organ function, were tested in a rabbit model. Compared to the other two CLI samples, the CLI2 with a molecular weight (M w) of 100kDa is advisable as a potential plasma expander for its strong expansion efficacy and no organ dysfunction. Moreover, CLI2 showed a high colloid osmotic pressure (COP) where the COP of 3% CLI2 is equal to that of 6% HES. Thus, much less CLI2 can be infused with the same effects as normal HES, and its potential side effects can be minimized. [Copyright &y& Elsevier]

• Green and non-toxic cellulose as the carbonaceous material for C-doping. • Combination of hydrothermal impregnation, calcination, and self-assembly. • Porous structure and superior high specific area of H-g-C 3 N 4 /WO 3. • Good photocatalytic performance of H-g-C 3 N 4 /WO 3 for tetracycline degradation. The preparation of heteroatom doping heterojunction photocatalysts with nontoxic carbonaceous materials and simple method still remains a challenge. Herein, ternary Z-scheme C-doped graphitic carbon nitride/tungsten oxide (C-doped g-C 3 N 4 /WO 3) was successfully fabricated via the hydrothermal impregnation with cellulose nanocrystal, high-temperature calcination, and electrostatic self-assembly with WO 3 nanocuboids in turns. Benefiting from the porous structure, high specific areas (57.20 m2 g−1), C-substitution, and the formation of Z-scheme heterojunction, the resulting photocatalyst exhibited narrower band-gap, enhanced visible-light absorption and separation of charge carrier, faster interfacial charge transfer, good oxidation/reduction capacities, and thus improved the photocatalytic activity performance. As such, this investigation will provide an effective route for not only incorporating semiconductors and heteroatoms into g-C 3 N 4 but also developing more heterojunction with markedly improved photocatalytic performance. [ABSTRACT FROM AUTHOR]