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Copolymerization is a facile and effective approach to develop functional polymers from two or more types of monomers. In the present work, we report an unexpected photoluminescence (PL) of poly[(methylenelactide)-co-(2-vinylpyridine)] (PLVPs) random copolymers, which possess intense blue emission in dilute solution with a quantum yield higher than 20%. Also, the PL of PLVPs exhibits the concentration quenching feature. Such intrinsic PL of PLVPs is attributed to the intra-chain and inter-chain interactions of pyridine and lactone rings. The dependence of emission on the molecular weights and monomer ratios of PLVPs, as well as excitation wavelength, in both solution and solid states was investigated. This work provides new insight into the design and preparation of luminescent polymers. [ABSTRACT FROM AUTHOR]

Magnetic materials display attractive properties for a wide range of applications. More recently, interest has turned to significantly enhancing their behaviour for advanced technologies, by exploiting the remarkable advantages that nanoscale materials offer over their bulk counterparts. Electrospinning is a high-throughput method that can continuously produce nanoscale fibres, providing a versatile way to prepare novel magnetic nanomaterials. This article reviews 20 years of magnetic nanomaterials fabricated via electrospinning and introduces their two primary production methods: electrospinning polymer-based magnetic fibres directly from solution and electrospinning fibrous templates for post-treatment. Continual advances in electrospinning have enabled access to a variety of morphologies, which has led to magnetic materials having desirable flexibility, anisotropy and high specific surface area. Post-treatment methods, such as surface deposition, carbonization and calcination, further improve or even create unique magnetic properties in the materials. This renders them useful in broad ranging applications, including electromagnetic interference shielding (EMS), magnetic separation, tissue engineering scaffolding, hyperthermia treatment, drug delivery, nanogenerators and data storage. The processing methods of electrospun magnetic nanofibres, their properties and related applications are discussed throughout this review. Key areas for future research have been highlighted with the aim of stimulating advances in the development of electrospun magnetic nanomaterials for a wide range of applications. [ABSTRACT FROM AUTHOR]

Amphiphobic fluorine materials hold great promise for fabricating self-cleaning membranes. However, the severely impeded water transport in hydrophobic fluorine-based membranes and the weak interaction with the substrate of the low-surface-energy fluorine materials represent two major obstacles for efficient water purification. Herein, we design an ultrathin fluorine-based membrane via coordination-driven metal-bridging assembly. An Fe3+-rich metal–organic layer is constructed on a porous substrate by coordination between polyphosphate ligands and Fe3+ ions, accompanied by the assembly of perfluorosulfonate polymer ligands (Nafion®) via the bridging effect of Fe3+ ions for the metal-bridging fluorine-based membrane (MBFM). By virtue of the flexible modulation of Fe3+ and unique self-assembly of Nafion®, a defect-free 58 nm-thick MBFM featuring an ultrahigh surface fluorine content (47.6 at%) and underwater superoleophobicity (∼160°) is achieved, which displays a superior water permeance of 125.2 L m−2 h−1 bar−1 (2–10 times higher than that of state-of-the-art membranes with dye rejections above 90%) and versatile resistance towards both spreading and non-spreading foulants (flux decline ratios below 8%). This metal-bridging assembly strategy may shed light on advanced membrane fabrication from rationally designed ligands and functional moieties. [ABSTRACT FROM AUTHOR]

Due to the complexity and heterogeneity of solid tumors, traditional clinical treatments often only achieve limited therapeutic effects. Tumor-associated macrophages (TAMs) play a key role in the development of solid tumors, and the elimination of solid tumors based on the tumor microenvironment has proven to be an effective therapeutic strategy. Here, we successfully developed Ru-based nanoparticles, Ru@ICG–BLZ NPs, with inflammation-responsive release ability, which could repolarize TAMs into M1 macrophages (with an antitumor role) and further produce hyperthermia and ROS to eliminate cancer cells. In vitro experiments showed that Ru@ICG–BLZ NPs had superior drug (ICG and BLZ-945) loading capacity and sensitive inflammation-responsive drug release behavior, which enhanced CT26 cell uptake and penetration ability. Furthermore, in vivo experiments showed that Ru@ICG–BLZ NPs could effectively up-regulate the expression of M1 markers (iNOS, and IL-12) and exert phototherapy to ablate solid tumor, without causing obvious damage to the surrounding tissues of the tumor. The lower toxicity and excellent antitumor ability of Ru@ICG–BLZ NPs could provide new ideas for the clinical transformation of nanomedicine. [ABSTRACT FROM AUTHOR]

The demand for fractionating organic molecules and salt ions via a membrane is increasing in various industries, but the sub-nanoscale difference in solute size makes it a critical challenge. Herein, amino-functionalized polyhedral oligomeric silsesquioxane (POSS) nanoparticles were employed as a molecular-level regulator to manipulate the nanopores of a polydopamine (PDA) membrane via a facile co-deposition process. By physical intercalation and chemical bonding of multifunctional POSS, increased nanoporosity was achieved within a narrow mean nanopore size range of 1.04–1.07 nm. The optimized POSS-PDA/PAN membrane exhibited desirable dye rejection (＞90%) and salt permeation (＞90%) with a high permeance of 1099 L m−2 h−1 MPa−1, which was 2–4 times higher than that of previously reported membranes with a similar dye rejection. Additionally, the rigid cage-like POSS nanoparticles cross-linked with the PDA membrane contributed to the reinforced alkali and compaction resistance. The synergy of mussel-inspired chemistry and multifunctional nanomaterials provided a novel strategy to engineer nanoporous membranes with a favorable physiochemical nanostructure for efficient and selective transport of both molecules and ions. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune disease and there is a lack of effective treatments. Nitric oxide (NO) plays an important role in inflammatory diseases, but the exact mechanism is not clear. We selected ruthenium complexes [Ru(Phen)2(4idip)](ClO4)2 (Ru) to induce the generation of NO in cells. SeNPs–PEG–RGD@Ru (Se@RuNPs) were prepared by modifying selenium nanoparticles with PEG, RGD and Ru. Se@RuNPs can promote uptake by Human Umbilical Vein Endothelial Cells (HUVECs) and trace the internalization and biodistribution. Experiments showed that Se@RuNPs target the abundant neovascular network of inflammatory sites to induce NO and promote the apoptosis of HUVECs and inhibit the growth of new vessels in local tissue. Moreover, NO activates autophagy by modulating signaling pathways related to AMPKα and mTOR, increasing the flux of autophagy, inhibiting the activity of NF-κB-p65, and modulating the levels of inflammatory cytokines. The exact mechanism of the inflammatory response regulated by NO is revealed. Histopathological analysis showed that the Se@RuNPs effectively reduced synovitis, cartilage corrosion and inflammatory cytokine expression levels, achieving satisfactory therapeutic effects. These unexpected results provide an effective strategy for target treatment of RA. [ABSTRACT FROM AUTHOR]

Co-delivery of gene and drug therapies for cancer treatment remains a major goal of nanocarrier research. In this study, mesoporous silica nanoparticles (MSNs) were used to co-deliver siRNA and doxorubicin (Dox) for redox-controlled release. The present nanocarrier (MSNs-SS-siRNA@Dox) has mesoporous silica cores that can be loaded with Dox, while siRNA connects to the core surface by disulfide linkage and plays a gatekeeper role. Disulfide linkages were also utilized to target intracellular GSH, and their cleavage led to the release of Dox and siRNA. Release of siRNA and Dox was correlated with GSH concentrations, and rapid release at 10 mM GSH reflected reductive cleavage of intermediate disulfide linkages. Subsequent experiments using an in vitro Dox delivery and release assay indicated that MSNs-SS-siRNA@Dox significantly enhanced the accumulation of Dox in cells compared with that after treatment with free Dox. Moreover, MSNs-SS-siRNA@Dox has sufficient efficiency to knock down target protein expression. More importantly, MSNs-SS-siRNA@Dox displayed great potential for tumor targeting and achieved satisfactory therapeutic effects on tumor growth inhibition in vivo. In summary, the present nanoparticles may provide an effective strategy for the design and development of controlled release and co-delivery of siRNA and drugs for cancer therapy. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid perovskites have been widely recognized as highly luminescent materials for efficient light-emitting devices. Herein, we report a simple perovskite-based metal–insulator–semiconductor (MIS) device structure with green light emission. Electron tunnelling and subsequent recombination in the semiconductor–insulator interface region is confirmed as the working mechanism of the perovskite light-emitting devices. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT), by producing reactive oxygen species (ROS), inhibits cancer cells and is an emerging and pioneering cancer therapeutic modality which can eliminate some of the drawbacks of other traditional anticancer therapies. To combine near-infrared (NIR) mediated PDT, chemotherapy and gene therapy in a synergistic manner, a novel NIR light activated photosensitizer for PDT was designed based on TiO2-coated Fe3O4 nanoparticle core/shell nanocarriers (Fe3O4@TiO2@mTiO2). The chemotherapeutic drug doxorubicin hydrochloride (DOX) was conjugated to the surface of the TiO2 mesopores through pH-reversible hydrazone bond linking and β-catenin siRNA was loaded in the mesopores. Fe3O4@TiO2@mTiO2–DOX/siRNA delivery systems have features and functions of magnetic targeting, fluorescence imaging, MRI diagnosis, and combination therapy through the simultaneous maneuvering of a magnet and NIR-mediated PDT. In vitro, Fe3O4@TiO2@mTiO2–DOX/siRNA effectively silences β-catenin gene, induces tumor cell apoptosis and consequently significantly enhances the cancer suppression effect of the synergistic therapeutic agent. Meanwhile, under NIR irradiation, excess ROS produced can further trigger tumor cell apoptosis. In vivo investigation confirmed that Fe3O4@TiO2@mTiO2–DOX/siRNA exhibited high tumor targeted specificity through MRI and fluorescence imaging, and optimal anti-tumor efficacy. The results verified its significant therapeutic effects on tumors by combination therapy consisting of magnetic targeting and NIR-mediated PDT. [ABSTRACT FROM AUTHOR]

The photophysics of organolead trihalide perovskites are still not fully understood. Here we report that the photoluminescence (PL) lineshape, decay features, and intensity of solution-processed CH3NH3PbI3−xClx films are highly sensitive to the ambience. The radiative recombination actually consists of two decay channels corresponding to recombination of extended and localized states, respectively. The PL decay can be well described by a model considering the carrier localization, surface band bending, and trapping–detrapping of carriers. [ABSTRACT FROM AUTHOR]

Human islet amyloid polypeptide (hIAPP) was found as amyloid aggregate deposits in the pancreatic islets of patients with type-2 diabetes and studies showed that insulin and its derivatives were the potent inhibitors of hIAPP aggregation. However, several emerging therapies with this goal showed limited success due to the instability and inefficiency of insulin derivatives. Nanosized graphene oxide (nGO) possesses high stability and affinity toward aromatic rings. In this study, an insulin-derived peptide, EALYLV, was stabilized by loading on nGO@PEG to inhibit aggregation and hIAPP-induced cytotoxicity. The results showed that nGO@PEG@EALYLV (abbreviated as nGO@PEG@E) can effectively inhibit the aggregation of hIAPP via electrostatic adsorption and specific binding to the active sites of hIAPP. We further evaluated the protective effect of nGO@PEG@E on INS-1 cells in the presence of hIAPP. Treatment with nGO@PEG@E could significantly elevate the viability of INS-1 cells, decrease the level of intracellular reactive oxygen species, and stabilize mitochondrial membrane potential. All the results indicated that nGO@PEG@E could inhibit the aggregation of hIAPP, which reduces its cytotoxicity. [ABSTRACT FROM AUTHOR]