•Biocompatible gelatin was successfully grafted on the surface of ZnO nanoparticles and thus prevent the aggregation of ZnO.•The prepared ZnO@Gelatin showed low cytotoxicity and can be used as biocompatible antibacterial agent.•The surface coating method was universal, and can be used to conecct other amino contained polymer or peptide onto the surface of ZnO.ZnO has been widely investigated as important biomaterials and antibacterial materials. However, the aggregation of nanoparticles and its potential toxicity may hinder its final application. Herein, biocompatible gelatin chains were grafted on the surface of ZnO via mussel inspired method to prevent the aggregation of the ZnO nanoparticles. The in vitro test showed that the gelatin can greatly improve the biocompatibility of ZnO, while the antibacterial properties of ZnO against both E. coli and S. aureus were maintained.

A critical challenge in the preparation of reinforced polymer nanocomposites is to prevent the aggregation of nanofillers. In this work, a novel poly(γ-benzyl-L-glutamate) (PBLG)-modified silicon dioxide@graphene oxide nanofiller (SiO2@GO-g-PBLG) was prepared via a continuous electrostatic complex and ring-opening polymerization (ROP) method. The grafted PBLG prevented the aggregation of SiO2 nanoparticles and GO sheets, realized the colloid stability of SiO2@GO-g-PBLG in organic solvents, and thus increased its phase interaction in a polymer matrix. The hybrid nanofiller greatly enhanced the mechanical properties of poly(L-lactide) (PLLA). As a typical feature, the tensile strength of PLLA nanocomposites with only 5 wt% of SiO2@GO-g-PBLG was 88.9 MPa, about 45% higher than that of pure PLLA. In addition, the hybrid nanofillers also have some positive effects on improving the thermal stability of PLLA. Therefore, SiO2@GO-g-PBLG was a promising hybrid nanofiller to reinforce polymers such as PLLA.

Novel composites based on cubic binary nickel cobaltite oxide intimately standing on nitrogen doped reduced graphene sheets (NRGO–NiCoO2) were prepared by a simple one step hydrothermal synthesis. The results showed that the highly crystalline NiCoO2 nanoparticles with a uniform size were homogeneously distributed on nitrogen-doped reduced graphene sheets (NRGO). The homogeneous composites combined NiCoO2, which has high specific capacitance, and NRGO, which has efficient electronic conductivity, to consequently yield low resistance conduction between metal oxides and graphene due to a barrier-free contact. The synergistic effect of NRGO substrates and NiCoO2 nanoparticles promoted the electrochemical performance of the composites. The electrochemical properties of NRGO–NiCoO2 can be easily tuned by altering the amount of nitrogen-composed reducer. The NRGO–NiCoO2 composites exhibited a remarkable specific capacitance of 508 F g−1 at 0.5 A g−1, an excellent rate performance in cyclic voltammetry test (from 5 to 90 mV s−1) and good galvanostatic charge–discharge measurements (from 0.5 to 20 A g−1). The capacitance was maintained at 93% of the original value even after 2000 cycles. The flexible devices were assembled, which possessed a specific capacitance of 58 F g−1 at 0.5 A g−1. This facile one-step strategy is an effective method for developing excellent supercapacitor electrodes.

•A new biodegradable poly(butylene succinate) (PBS)/poly(Z-l-lysine) (PZlys) composites were successfully prepared through physical blend.•PZlys may greatly affected the crystallization behaviors of PBS without changing its crystalline structure.•The degradation speed of PBS may be greatly accelerated by introduction of PZlys in PBS matrix.A new type of biodegradable poly(butylene succinate) (PBS)/poly(Z-l-lysine) (PZlys) composites were prepared. The crystallization behaviors were investigated by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and polarizing optical microscopy (POM) and the results showed that PZlys can restrict the crystallization of PBS, the crystallization speed of PBS/PZlys were slower than that of PBS, and the crystallization degree of the composites were smaller than that of PBS. However, the WAXD results showed that the incorporation of PZlys did not change the crystalline structure of PBS. The in vitro degradation experiments demonstrated that the degradation speed of the composites were faster than that of PBS. Moreover, the mechanical properties of the composites showed that the composites with a proper composition (for example, 80/20) can keep the mechanical properties of PBS without evident difference, which implied that the composites might be potentially useful as biodegradable materials.

•The ZnO@PNIPAM hybrid was prepared via ATRP.•The ZnO@PNIPAM hybrid showed thermal responsive properties.•The ZnO@PNIPAM hybrid can work as a thermal and pH responsive drug delivery system.A smart ZnO@PNIPAM hybrid was prepared by grafting thermal responsive poly(N-isopropylacrylamide) (PNIPAM) on zinc oxide (ZnO) nanoparticles via surface-initiated atom transfer radical polymerization (ATRP). The thermal gravimetric analysis (TGA) shows that the grafting amount of PNIPAM was about 38%, and the SEM images show that the PNIPAM chains can prevent the aggregation of ZnO nanoparticles. The responsive properties of ZnO@PNIPAM were measured by photoluminescence spectra, and the results demonstrate that the PNIPAM chains grafted on ZnO surfaces can realize reversible thermal responsive and photoluminescence properties. An anticancer drug, doxorubicin (Dox), was used as a model drug and loaded into the hybrid nanoparticles, and an in vitro drug release test implied that ZnO@PNIPAM could work as a thermal responsive drug delivery system. Furthermore, pH sensitive drug releases were carried out in acetate buffer at pH 5.0 and pH 6.0 and in water at pH 7.0, and the results showed evident pH dependency, showing its pH responsive properties.In this manuscript, thermal responsive poly(N-isopropylacrylamide) (PNIPAM) was grafted on the surface of ZnO nanoparticles. The obtained ZnO@PNIPAM hybrid showed reversible thermal responsive photoluminescent properties, and can also work as a thermal and pH responsive drug delivery system.

Novel composites based on cubic binary nickel cobaltite oxide intimately standing on nitrogen doped reduced graphene sheets (NRGO–NiCoO2) were prepared by a simple one step hydrothermal synthesis. The results showed that the highly crystalline NiCoO2 nanoparticles with a uniform size were homogeneously distributed on nitrogen-doped reduced graphene sheets (NRGO). The homogeneous composites combined NiCoO2, which has high specific capacitance, and NRGO, which has efficient electronic conductivity, to consequently yield low resistance conduction between metal oxides and graphene due to a barrier-free contact. The synergistic effect of NRGO substrates and NiCoO2 nanoparticles promoted the electrochemical performance of the composites. The electrochemical properties of NRGO–NiCoO2 can be easily tuned by altering the amount of nitrogen-composed reducer. The NRGO–NiCoO2 composites exhibited a remarkable specific capacitance of 508 F g−1 at 0.5 A g−1, an excellent rate performance in cyclic voltammetry test (from 5 to 90 mV s−1) and good galvanostatic charge–discharge measurements (from 0.5 to 20 A g−1). The capacitance was maintained at 93% of the original value even after 2000 cycles. The flexible devices were assembled, which possessed a specific capacitance of 58 F g−1 at 0.5 A g−1. This facile one-step strategy is an effective method for developing excellent supercapacitor electrodes.