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A new strategy was developed to prepare nanoscale porous carbon spheres (PCSs) using cross‐linked chitosan/poly(γ‐glutamic acid) colloidal particles as precursor. The fabricated cross‐linked chitosan/poly(γ‐glutamic acid) colloidal particles (Ca2+/CS/γ‐PGA CPs) were prepared from the self‐assembly of negatively charged poly(γ‐glutamic acid) and positively charged chitosan, and the cross‐linking of Ca2+ in aqueous solution, via the electrostatic interaction. After lyophilization, the Ca2+/CS/γ‐PGA CPs power was obtained, followed by carbonization in a tube furnace under N2 atmosphere. Finally, the products were washed by hydrochloric acid, obtaining PCSs with hierarchical pore structure and super‐hydrophobicity. The prepared PCSs exhibited excellent separation performance for oil‐in‐water emulsions. [ABSTRACT FROM AUTHOR]

Introducing lysozyme (Lys) to dopamine-modified poly (γ-glutamic acid) (PGA-DA), the self-assembled colloidal nanoparticles (Lys/PGA-DA) were obtained through the electrostatic, hydrogen bonding and hydrophobic interactions. After mixing vigorously colloidal nanoparticles and white oil, o/w gel-like emulsion formed. The influences of ionic strength on the properties and emulsifying performances of colloidal nanoparticles and the activity of Lys in emulsions were investigated in detail. Scanning electron microscopy (SEM) characterization and rheological measurements demonstrated that emulsifying properties of colloidal nanoparticles were significantly improved with increasing salt concentration. Moreover, fluorescence and circular dichroism (CD) measurements showed that the addition of salt might induce conformational changes of Lys in colloidal nanoparticles resulting in a more ordered secondary structure, thereby leading to an increase in enzyme activity. In vitro cytotoxicity of emulsions revealed that emulsions showed a low cytotoxicity and a high bioactivity. All results verified that the obtained emulsion could have potential application in food, pharmaceutical, and cosmetic fields. [ABSTRACT FROM AUTHOR]

Abstract: The contact form of the heterojunction interface has an importance effect on interfacial photoelectron transfer and photocatalytic property. Here, C/C3N4 heterojunction with three types of interface contact between C and C3N4 have been constructed, including C/C3N4-I, C/C3N4-HI, C/C3N4-D. The physico-chemical properties of the prepared catalysts were characterized by TEM, XRD, XPS, Raman, FT-IR, UV-VIS DRS and UPS. The results indicate that the interface composition (Cg/Cs, Nt/Ns) and valence band characteristic of the photocatalysts are strongly dependent on the interface contact form of C and C3N4. Compared with the C/C3N4-HI and C/C3N4-D, the sample C/C3N4-I present higher ratios of Cg/Cs and Nt/Ns, stronger light response and appropriate band locations. These findings reveal that the C deposited on the surface of C3N4 promotes the efficiencies of light harvest and charge carrier separation, ultimately resulting in an enhanced photocatalytic performance for pure water splitting.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Dopamine modified γ-polyglutamic acid ( γ-PGA-DA) copolymer and melamine (Mel) can self-assemble into Mel/ γ-PGA-DA micelles via weak intermolecular interactions in aqueous solution containing small amount of methanol. When Mel/ γ-PGA-DA micellar solution was cast on the surface of formvar stabilized with carbon support films, the lotus-like nano-architectures were formed on the surface of substrate via hierarchical assembly of micelles. The size of lotus-like nanoarchitectures was approximately 200 nm×500 nm. The possible driving forces for hierarchical assembly of micelles were the solution fluid and interaction between micelles. The hierarchical assembly of micelles was similar to the fractal aggregation of inorganic particles and a possible reason was discussed. [ABSTRACT FROM AUTHOR]