This review focuses on the synthesis of multicompartment block copolymer nanoparticles (MBCNs) via solution self-assembly and polymerization-induced self-assembly (PISA).

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Osteoarthritis (OA) is a degenerative joint disease mainly characterized by cartilage degradation. Interleukin-1β (IL-1β) contributes to OA pathogenesis by enhancing oxidative stress and inflammation. Melatonin reportedly elicits potent protection against OA. However, the role of melatonin and underlying mechanism in IL-1β-stimulated chondrocytes remain largely unclear. In this study, we found that melatonin inhibited IL-1β-induced toxicity and sirtuin 1 (Sirt1) enhancement in human chondrocytes. Melatonin reduced the IL-1β-increased nicotinamide phosphoribosyltransferase (NAMPT) expression and the NAD+ level in chondrocytes in a Sirt1-dependent manner. In turn, the inhibitory effect of melatonin on Sirt1 was mediated by NAMPT. Moreover, melatonin suppressed IL-1β-induced Sirt1-mediated matrix metalloproteinase (MMP)-3 and MMP-13 production. Melatonin also decreased the Sirt1-steered nuclear factor of activated T cells 5 (NFAT5) expression in IL-1β-challenged chondrocytes. NFAT5 depletion mimicked the suppressive effects of melatonin on IL-1β-elevated production of inflammatory mediators, including tumor necrosis factor-α (TNF-α), IL-1β, prostaglandin E2 (PGE2), and nitric oxide (NO) in chondrocytes. TNF-α, IL-1β, PGE2, or NO decrease caused the similar reduction of MMP-3 and MMP-13 by melatonin in IL-1β-insulted chondrocytes. Highly consistent with in vitro findings, in vivo results demonstrated that melatonin repressed the expression of relevant genes in rat OA pathogenesis in anterior cruciate ligament transection model. Overall, these results indicate that melatonin effectively reduced IL-1β-induced MMP production by inhibiting Sirt1-dependent NAMPT and NFAT5 signaling in chondrocytes, suggesting melatonin as a potential therapeutic alternative for chondroprotection of OA patients.

We report high-performance star brush block copolymer electrolytes (SBBCEs) composed of 2-arm star polymer of [poly[poly(ethylene glycol) methyl ether acrylate]b-polystyrene] 2 . The physically crosslinked structure endows SBBCEs with excellent thermal stability and considerable mechanical strength, high ionic conductivity of 2.1 × 10 −4 S cm −1 at 28 °C, wide electrochemical stability window up to 5.6 V, and good interfacial compatibility with lithium anode. A s s e m b l e d L i F e P O 4 | S B B C E | L i a n d N i -r i c h L i -Ni 0.89 Co 0.09 Mg 0.02 O 2 |SBBCE|Li cells deliver superior ambienttemperature cycling performance with high reversible capacities, high Coulombic efficiency, and outstanding cyclic stability at considerable rate of 0.5 C. This proposed idea of employing physically crosslinked structure of brush block copolymer without any chemical crosslinker may broaden a new way to design high-performance polymer electrolytes.

Autonomous indication of mechanical damage and self-healing epoxy materials was conducted using 2′,7′-dichlorofluorescein (DCF) and glycidyl methacrylate (GMA) solution.

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A repeatable self-healing epoxy composite mechanically enhanced by graphene nanosheets (GNS) was prepared from an epoxy monomer with Diels-Alder (DA) bonds, octanediol glycidyl ether (OGE) and polyether amine (D230). The GNS/epoxy composites, with a maximum tensile modulus of 14.52 AE 0.45 MPa and elongation at break more than 100%, could be healed several times under Infrared (IR) light with the healing efficiency as high as 90% through the molecule chain mobility and the rebonding of reversible DA bonds between furan and maleimide. Also, they displayed excellent recyclable ability by transforming into a soluble polymer, which offers a wide range of possibilities to produce epoxy flexible materials with healing and removable abilities. † Electronic supplementary information (ESI) available: Comparison of the prepared self-healing epoxy polymers in this paper with other conventional epoxy polymer, TEM graph of GNS/FDB/OGE/D230 epoxy composite lled with 0.5 wt% GNS. See Scheme 1 The preparation schematic diagram of GNS/epoxy flexible composites embedded with DA bonds.This journal is