A supercapacitor electrode composed of a polyindole (PIn)-modified carbon nanotubes (CNTs) composite (CNTs/PIn) decorated with Co3O4 nanoparticles was synthesized to enhance the electrochemical performance. The PIn shell could improve the electric conductivity and the dispersion of CNTs, and the functional groups of PIn are conducive to anchoring the Co3O4 particles on the CNTs/PIn composite with large effective surface area, leading to a high specific capacitance of 442.5 F g−1. Moreover, the all-solid-state supercapacitor exhibits a high energy density (42.9 W h kg−1) at a power density of 0.4 kW kg−1 and excellent cycling performance (90.2% capacitance retention after 5000 cycles), demonstrating its promising application as an efficient electrode material for electrochemical capacitors.

Blood compatibility and cytocompatibility are key requirements of blood-contacting biomaterials for biomedical applications. Here, we showed the general zwitterionic surface modification of cellulose membrane (CM) substrates, via surface-initiated atom transfer radical polymerization (SI-ATRP), to enhance the anti-biofouling ability without compromising the cytocompatibility of the substrates. Robust X-ray photoelectron spectroscopy (XPS) characterization revealed the successful construction of three zwitterionic brushes, which significantly increased the hydrophilicity of the CM substrates. The zwitterionic brushes-modified CM substrates can significantly reduce the non-specific adsorption of proteins, platelet adhesion and cell attachment, indicating a generally and significantly improved anti-biofouling ability, which is comparable to that of the benchmark anti-fouling poly(ethylene glycol) (PEG) surface. Inspired by the varied in situ cell morphology observed on different substrates, we further investigated the cytocompatibility of the zwitterionic coatings and showed the general cytocompatibility of zwitterionic brush-modified CM surfaces based on both 2D (cell cultured with zwitterionic surfaces) and 3D cell cultures (cell encapsulation in zwitterionic hydrogels). This work provides a promising general approach to enhancing the blood compatibility of cellulose-based materials without compromising their cytocompatibility. The cytocompatibility observation may enrich the perceptions of the zwitterionic modification of substrates and may be beneficial for the in vivo applications of zwitterionic materials.

Highly dispersed polypyrrole nanowires are decorated on reduced graphene oxide sheets using a facile in situ synthesis route. The prepared composites exhibit high dispersibility, large effective surface area, and high electric conductivity. All-solid-state flexible supercapacitors are assembled based on the prepared composites, which show excellent electrochemical performances with a specific capacitance of 434.7 F g–1 at a current density of 1 A g–1. The as-fabricated supercapacitor also exhibits excellent cycling stability (88.1% capacitance retention after 5000 cycles) and exceptional mechanical flexibility. In addition, outstanding power and energy densities were obtained, demonstrating the significant potential of prepared material for flexible and portable energy storage devices.Keywords: energy storage; flexible; highly dispersed; polypyrrole nanowire; reduced graphene oxide; supercapacitors

Poly(3-trimethoxysilyl-propyl-methacrylate) (PMPS) and poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) with various compositions was synthesized for the surface modification of currently commercially available lenses. The properties of these anti-biofouling contact lenses were investigated, which indicated that the modified contact lenses had significant surface-wettability improvement, superior antibacterial adhesion properties and resistance to protein adsorption. PMPS-b-PMPC can be immobilized on currently commercially available lenses by one-step modification while maintaining their excellent clinical performance and biocompatibility. The prepared anti-biofouling contact lenses may be realized in a more convenient and feasible way.

•Facile surface modification of silicone rubber with functional brushes•Modified SR surfaces have improved resistance to nonspecific protein adsorption.•Modified SR surfaces have excellent resistance to platelet adhesion.•Zwitteironic surface significant improvement in blood compatibility•Could inspire many creative uses of SR based materials for biomedicalA facile approach to modify silicone rubber (SR) membrane for improving the blood compatibility was investigated. The hydrophobic SR surface was firstly activated by air plasma, after which an initiator was immobilized on the activated surface for atom transfer radical polymerization (ATRP). Three zwitterionic polymers were then grafted from SR membrane via surface-initiated atom transfer radical polymerization (SI-ATRP). The surface composition, wettability, and morphology of the membranes before and after modification were characterized by X-ray photoelectron spectroscopy (XPS), static water contact angle (WCA) measurement, and atomic force microscopy (AFM). Results showed that zwitterionic polymers were successfully grafted from SR surfaces, which remarkably improved the wettability of the SR surface. The blood compatibility of the membranes was evaluated by protein adsorption and platelet adhesion tests in vitro. As observed, all the zwitterionic polymer modified surfaces have improved resistance to nonspecific protein adsorption and have excellent resistance to platelet adhesion, showing significantly improved blood compatibility. This work should inspire many creative uses of SR based materials for biomedical applications such as vessel, catheter, and microfluidics.

AB diblock copolymers comprised of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) and poly(3-methacryloxypropyl trimethoxysilane) (PMTSi) segments, which are used for biocompatible coatings, were investigated. Block copolymers with various compositions were synthesized by atomic transfer radical polymerization (ATRP). The obtained copolymers were dissolved in an ethanol solution, and dynamic light scattering showed that all block copolymers were capable of existing as micelles. After a convenient “one-step” reaction, the cellulose membranes could be covalently modified by these copolymers with stable chemical bonds (C–O–Si and Si–O–Si). Block copolymers with different PMPC chain length were applied to surface modification to find the most suitable copolymer. The functional MPC density can be controlled by adjusting the ratio of the two monomers (MPC and MTSi), which also affect surface properties, including the surface contact angle, surface morphology, and number of functional PC groups. The low-fouling properties were measured by protein adsorption, platelet adhesion and activation, and cell adhesion. Protein adsorption of bovine serum albumin (BSA), fibrinogen, and human plasma were also tested and a moderate monomer composite was attained. The protein adsorption behavior on the novel interfaces depends both on MPC density and PMPC chain length. Platelet adhesion and activation were reduced on all the modified surfaces. The adhesion of Human Embryonic Kidney 293 (293T) cells on the coated surfaces also decreased.Keywords: ATRP; biocompatibility; cellulose; copolymer; micelles; surface modification;

The viscosity of CaCO3/poly(acrylic acid) grafted methoxyl poly(ethylene oxide) (PAA-g-MPEO) aqueous suspensions was influenced by length of the branched-chain and content of PAA-g-MPEO. The viscosity of CaCO3/PAA-g-MPEO suspensions first decreased and then increased with increasing length of branched-chain of PAA-g-MPEO at the same PAA-g-MPEO content. The viscosity of CaCO3 suspensions containing PAA-g-MPEO with short branched-chain (\( \bar{M}_{n} \) = 200 g/mol and 600 g/mol) decreased with increasing the PAA-g-MPEO content. However, the viscosity of CaCO3 suspensions containing PAA-g-MPEO with long branched-chain (\( \bar{M}_{n} \) = 1500 g/mol) increased with increasing the PAA-g-MPEO content. The size distribution of CaCO3 particles in CaCO3 suspensions containing PAA-g-MPEO with the short branched-chain became narrower and the average size decreased with increasing length of the branched-chain. This is due to the steric hindrance of branched-chain of the PAA-g-MPEO adsorbing on surface of the CaCO3 particles increased with increasing length of the branched-chain. The size distribution of CaCO3 particles in CaCO3 suspensions containing PAA-g-MPEO with the long branched-chain had two regions, and the average size increased compared with that of CaCO3 particles in the CaCO3 suspensions containing PAA-g-MPEO with the short branched-chain. This is due to the flocculation of fractional CaCO3 particles induced by “tangle” between the long branched-chain of PAA-g-MPEO adsorbing on surface of CaCO3 particles.

A facile preparation of N-doped anatase TiO2 hollow spheres in sub-micron size with good morphology was developed in this work. Polystyrene latexes in size of 470 nm were used as the templates to fabricate polystyrene/TiO2 core–shell spheres in the sol–gel process. Here the ammonia/triethanolamine positive/negative catalyst pair was first employed to control the coating of TiO2 onto the surface of the PS templates. And synchronously triethanolamine served also as the N source. The N-doped TiO2 hollow spheres with good morphology were first obtained here after calcinations of the core–shell spheres. It was proved that the hollow spheres have distinct visible light response from 390 to 600 nm. The content of the N doping could be easily adjusted by changing the amount of triethanolamine added and the optical response of TiO2 hollow spheres shifted more to the visible light as the content of the N doping increasing. The N doping could increase the separation efficiency of the photoinduced electron and hole, so the intensity of photoluminescence decreased obviously with increased content of the N doping.

Zwitterionic phosphobetaine bearing a hydroxyl and a zwitterionic group, 8-hydroxy-2-octyl phosphorylcholine (HOPC), was synthesized and constructed to the surface of silk fibroin(SF) films in order to improve the hemocompatibility of fibroin films by a an isocyanate head group. The surface characteristics of the modified films were measured by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and electron spectroscopy for chemical analysis (ESCA), displaying the successful immobilization of Zwitterionic phosphobetaine on the surface of these fibroin films. Moreover, the further platelet adhesion test in platelets rich plasma (PRP) of human beings showed the zwitterionic phosphobetaine led mainly to good nonthrombogenicity. The experimental results indicated a reasonable approach to improve the blood compatibility of fibroin films.

Novel ammonia and triethanolamine assisted sol–gel synthesis method was developed to fabricate the N-doped TiO2 hollow spheres. The prepared hollow spheres were in submicron size and had good morphology and high specific surface area. Polystyrene (PS) latexes in size of 470 nm were used as the templates to fabricate PS/TiO2 core–shell spheres. Here ammonia and triethanolamine was first employed together to control the sol–gel process. The N-doped TiO2 hollow spheres were got after calcinations of the core–shell spheres by using triethanolamine as N source, and the amount of doped N could be easily adjusted by changing the amount of triethanolamine. The hollow spheres had distinct visible light response, and the optical response shifted more to the visible region as the amount of doped N increases. The photodegradation of methylene blue expressed the high photocatalytic activity of the N-doped TiO2 hollow spheres under visible light.

A p-vinylbenzyl sulfobetaine was grafted from cellulose membrane (CM) using surface-initiated atom transfer radical polymerization for blood compatibility improvement. Surface structure, wettability, morphology, and thermal stability of the CM substrates before and after modification were characterized by attenuated total reflectance Fourier transform infrared spectra, X-ray photoelectron spectroscopy measurement, water contact angle measurement, atomic force microscopy, and thermogravimetric analysis, respectively. The results showed that zwitterionic brushes were successfully fabricated on the CM surfaces, and the content of the grafted layer increased gradually with the polymerization time. The blood compatibility of the CM substrates was evaluated by protein adsorption tests and platelet adhesion tests in vitro. It was found that all the CMs functionalized with zwitterionic brush showed improved resistance to nonspecific protein adsorption and platelet adhesion, even though the grafting polymerization was conducted for several minutes.

A supercapacitor electrode composed of a polyindole (PIn)-modified carbon nanotubes (CNTs) composite (CNTs/PIn) decorated with Co3O4 nanoparticles was synthesized to enhance the electrochemical performance. The PIn shell could improve the electric conductivity and the dispersion of CNTs, and the functional groups of PIn are conducive to anchoring the Co3O4 particles on the CNTs/PIn composite with large effective surface area, leading to a high specific capacitance of 442.5 F g−1. Moreover, the all-solid-state supercapacitor exhibits a high energy density (42.9 W h kg−1) at a power density of 0.4 kW kg−1 and excellent cycling performance (90.2% capacitance retention after 5000 cycles), demonstrating its promising application as an efficient electrode material for electrochemical capacitors.

Blood compatibility and cytocompatibility are key requirements of blood-contacting biomaterials for biomedical applications. Here, we showed the general zwitterionic surface modification of cellulose membrane (CM) substrates, via surface-initiated atom transfer radical polymerization (SI-ATRP), to enhance the anti-biofouling ability without compromising the cytocompatibility of the substrates. Robust X-ray photoelectron spectroscopy (XPS) characterization revealed the successful construction of three zwitterionic brushes, which significantly increased the hydrophilicity of the CM substrates. The zwitterionic brushes-modified CM substrates can significantly reduce the non-specific adsorption of proteins, platelet adhesion and cell attachment, indicating a generally and significantly improved anti-biofouling ability, which is comparable to that of the benchmark anti-fouling poly(ethylene glycol) (PEG) surface. Inspired by the varied in situ cell morphology observed on different substrates, we further investigated the cytocompatibility of the zwitterionic coatings and showed the general cytocompatibility of zwitterionic brush-modified CM surfaces based on both 2D (cell cultured with zwitterionic surfaces) and 3D cell cultures (cell encapsulation in zwitterionic hydrogels). This work provides a promising general approach to enhancing the blood compatibility of cellulose-based materials without compromising their cytocompatibility. The cytocompatibility observation may enrich the perceptions of the zwitterionic modification of substrates and may be beneficial for the in vivo applications of zwitterionic materials.

Correction for ‘Anti-biofouling ability and cytocompatibility of the zwitterionic brushes-modified cellulose membrane’ by Pingsheng Liu et al., J. Mater. Chem. B, 2014, 2, 7222–7231.