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The catalyst employed in industries for the hydrogen evolution reaction in seawater electrolyte suffers from scarcity, unsatisfactory catalytic activity and stability at large current density. To produce hydrogen under large current densities, the electrode requires both robust mechanical stability and high intrinsic catalytic activity. It remains challenging to create an electrode that ensures the exposure of catalytic sites while strengthening the binding force between the substrate and the catalyst, particularly in natural alkaline seawater electrolytes. In this work, the multi-heterostructure H2–NiCo2O4@NiMoO4 electrocatalyst with multi-interface was developed through a facile hydrothermal strategy, followed by a thermal reduction strategy. In 1 M KOH aqueous solution, the H2–NiCo2O4@NiMoO4 exhibited an overpotential of 216 mV at 1000 mA cm−2 and a low Tafel slope of 29 mV dec−1. Furthermore, a low Tafel slope of 31 mV dec−1 and a current density of 1000 mA cm−2 could be achieved with only 249 mV in seawater electrolytes (pH = 14). Remarkably, the H2–NiCo2O4@NiMoO4 electrocatalyst required only 445 and 345 mV to reach an ultra-high current density of 4000 mA cm−2 in 1 M KOH and alkaline natural seawater electrolyte, respectively. Additionally, the H2–NiCo2O4@NiMoO4 electrocatalyst demonstrated excellent long-term stability of over 12 h in both 1 M KOH and alkaline seawater electrolyte. This work may pave a novel avenue for the development of excellent non-noble metal catalysts for hydrogen evolution reactions in industrial applications. [ABSTRACT FROM AUTHOR]

The importance of bioink suitability for extrusion bioprinting tissue‐like constructs cannot be overemphasized. Owing to their excellent accessibility, alginate (Alg) ‐based bioinks are widely used. However, the printability accuracy and post‐printing stability of current Alg‐based bioinks remain challenging, especially for large‐size fabrication. Herein, an improvement strategy for pre‐crosslinking and post‐crosslinking of methacrylated Alg (AlgMA) bioinks in extrusion bioprinting is presented via introduction of methacrylated ɛ‐polylysine (ɛ‐PLMA) as a small‐molecule polycationic crosslinker. Due to their electrostatic interaction and covalent bonding, ɛ‐PLMA significantly reinforce the operability and prolong stability of AlgMA bioinks, in comparison with single‐molecule Ca2+ or large‐molecule methacrylated gelatin as pre‐crosslinkers. Meanwhile, attributed to their regulation of a charged microenvironment (−345.25 to 121.55 mV) and hydrophilicity (26.64° to 52.00°), the cells in bioprinted AlgMA/PLMA constructs demonstrated improved viability and vitality. Therefore, such a strategy of introducing small‐molecule cationic crosslinker ɛ‐PLMA is a promising booster for improving Alg‐based extrusion bioprinting, potential to extend its biomedical applications. [ABSTRACT FROM AUTHOR]

A tetraphenylethene-based Pd2L4 metallacage was self-assembled from four TPE-pyridine ligands with two Pd2+ ions. This metallacage with D4 symmetry exhibited a classical aggregation-induced emission property in different solvents and reversible stimuli-responsive behaviour with chloride ions and silver ions, successively. [ABSTRACT FROM AUTHOR]

A crystalline nanotubular framework was constructed by cucurbit[8]uril (CB[8]) molecules in the presence of a molecular chaperone. Compared with amorphous CB[8], the framework exhibits highly selective adsorption for CO2 over N2, CH4, and H2. [ABSTRACT FROM AUTHOR]

As a growth repair factor, mechano-growth factor (MGF) and its 24 amino acid peptide analogs corresponding to the unique C-terminal E-domain (MGF-Q24E) positively regulate bone regeneration. MGF-Q24E was introduced into the poly(D, L-lactic acid) (PDLLA) to improve bone regeneration in our previous study. MGF-Ct24E-grafted PDLLA was chemically characterized and showed potential as a biofunctional polymer. In this study, we evaluated the cytocompatibility of MGF-Ct24E chemically grafted and physically blended with maleic anhydride modified PDLLA, relative to maleic anhydride modified PDLLA (MPLA) as the control. The surface properties of these three polymer films were characterized with scanning electron microscopy and X-ray photoelectron spectroscopy. Rat calvarial osteoblasts were seeded on the three polymer films, and cell adhesion, spreading, and proliferation were assessed with an inverted microscope, laser scanning confocal microscope, and a cell counting kit-8, respectively. The alkaline phosphatase activity and extracellular calcium production were exploited to characterize the differentiation and mineralization of rat calvarial osteoblasts on various polymer films. The results revealed that compared with MPLA, MGF-024E-MPLA, and MGF-Q24E/MPLA blends promoted adhesion, spreading, proliferation, and the later differentiation and mineralization process of rat calvarial osteoblasts. In addition, the positive effect of MGF-Q24E-MPLA on rat calvarial osteoblasts was maintained longer than the MGF-Q24E/MPLA blends. In conclusion, MGF-Q24E-MPLA synthesized chemically might be a promising biomaterial for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Two kinds of shape-controllable and fluorescent supramolecular organic frameworks (cuboid or spheroid) are constructed hierarchically from CB[8] and tetraphenylethylene derivatives through host-guest interaction in water. These two fluorescent SOFs exhibit intriguing and varied photophysical properties, including large red-shifts (up to 82 nm) and stimuli-responsive behavior to competitive guest by binding with CB[8], the turn-on fluorescence of which is applied in cellular imaging., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

As a growth repair factor, mechano-growth factor (MGF) and its 24 amino acid peptide analogs corresponding to the unique C-terminal E-domain (MGF-Ct24E) positively regulate bone regeneration. MGF-Ct24E was introduced into the poly(D, L-lactic acid) (PDLLA) to improve bone regeneration in our previous study. MGF-Ct24E-grafted PDLLA was chemically characterized and showed potential as a biofunctional polymer. In this study, we evaluated the cytocompatibility of MGF-Ct24E chemically grafted and physically blended with maleic anhydride modified PDLLA, relative to maleic anhydride modified PDLLA (MPLA) as the control. The surface properties of these three polymer films were characterized with scanning electron microscopy and X-ray photoelectron spectroscopy. Rat calvarial osteoblasts were seeded on the three polymer films, and cell adhesion, spreading, and proliferation were assessed with an inverted microscope, laser scanning confocal microscope, and a cell counting kit-8, respectively. The alkaline phosphatase activity and extracellular calcium production were exploited to characterize the differentiation and mineralization of rat calvarial osteoblasts on various polymer films. The results revealed that compared with MPLA, MGF-Ct24E-MPLA, and MGF-Ct24E/MPLA blends promoted adhesion, spreading, proliferation, and the later differentiation and mineralization process of rat calvarial osteoblasts. In addition, the positive effect of MGF-Ct24E-MPLA on rat calvarial osteoblasts was maintained longer than the MGF-Ct24E/MPLA blends. In conclusion, MGF-Ct24E-MPLA synthesized chemically might be a promising biomaterial for bone tissue engineering.

Mechano-growth factor (MGF) is an alternative splicing variant of Insulin-like growth factor I. MGF and its 24 amino acid peptide analog corresponding to the unique C-terminal E-domain (MGF-Ct24E) are the positive regulator for tissue regenesis in bone. A novel biomimetic poly(D, L-lactic acid) (PDLLA) modification was designed and synthesized based on MGF-Ct24E grafted maleic anhydride modified PDLLA (MPLA). MGF-Ct24Es were grafted into the side chain of MPLA via a stable covalent amide bond using 1-ethyl-3-(3-dimethyllaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide as the condensing agent to produce biomimetic MPLA materials (MGF-Ct24E-MPLA). Fourier transform infrared spectrometry, amino acid analyzer, and elementary analysis were used to characterize the MGF-Ct24E-MPLA. The hydrophilicity of MGF-Ct24E-MPLA was evaluated by means of the water-uptake ratios and static water contact angle. Data revealed that the grafting efficiency of MGF-Ct24E was about 29.9%. MGF-Ct24E-MPLA had better hydrophilicity than PDLLA and MPLA. The osteoblasts behavior of proliferation, differentiation, and mineralization on PDLLA, MPLA, and MGF-Ct24E-MPLA films was investigated and the results indicated that the introduction of MGF-Ct24E could improve osteoblasts proliferation, mineralization, and delay differentiation. The MGF-Ct24E modified MPLA with higher bioactivity may have potential application for bone tissue engineering., (Copyright © 2012 Wiley Periodicals, Inc.)