Currently, sustainability initiatives that use green chemistry to improve and/or protect our global environment are becoming focal issues in many fields of research. Instead of using toxic chemicals for the reduction and stabilisation of metallic nanoparticles, the use of various biological entities has received considerable attention in the field of nanobiotechnology. Among the many possible natural products, polysaccharides and biologically active plant products represent excellent scaffolds for this purpose. Polysaccharides have hydroxyl groups, a hemiacetal reducing end, and other functionalities that can play important roles in both the reduction and the stabilisation of metallic nanoparticles. Among the various categories of compounds in plants that have potent biological activities, phytochemicals are emerging as an important natural resource for the synthesis of metallic nanoparticles. The focus of this review is the application of polysaccharides and phytochemicals in the green synthesis of gold and silver nanoparticles to afford biocomposites with novel uses in nanomedicine and as nanocomposites.

DNA vaccine is a third generation vaccine type based on concepts and techniques of molecular biology. It can closely mimic live infections and induce both antibody and cell mediated immune responses and thus has much potential for treating chronic viral infection and cancer. How do we transport the DNA vaccine to the right target cells in lymphoid tissues and organs? How do we achieve high and robust gene transfection efficiency while simultaneously inducing DC maturation and antigen presentation? These questions pose significant challenges and addressing them may require serious efforts in developing better biomaterials as carriers. This review is dedicated to the discussion of polymers as nanoscale carriers for the DNA vaccine. We summarize recent advances in polymer science and engineering to overcome multilevel hurdles for DNA vaccine delivery and conclude with thoughts on challenges and opportunities that may shape the future of polymers in DNA vaccination.

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Synthesis of hollow capsules by the polymerization-induced interfacial self-assembly (PIISA) approach is reported in this research. In a typical PIISA process, a hydrophilic polymer synthesized by reversible addition–fragmentation chain transfer (RAFT) polymerization is used as macro-CTA, toluene droplets in water are used as templates, and methyl methacrylate (MMA) is used as a monomer. Because of the insolubility in toluene, the initial chain extension of macro-CTA with MMA is performed in water. With an increase in PMMA block length, the formed block copolymer (BCP) chains migrate to the liquid–liquid interface with hydrophilic blocks in the aqueous phase and PMMA blocks in the oil phase, so that the interfacial tension is reduced. Because the concentration of MMA in the aqueous phase is lower than that in the oil phase, the interfacial RAFT polymerization of MMA exhibits an improved polymerization rate, as compared to the polymerization in the aqueous phase. Upon the addition of a cross-linker, cross-linked hollow capsules are synthesized. The average size of the cross-linked capsules decreases with an increase in the cross-linker content. It is demonstrated that inorganic particles and organic compounds can be encapsulated in the voids of the capsules. PIISA is a process combining chain extension and interface-directed self-assembly of BCP chains, and it is reasonable to expect that this approach will find applications in the synthesis of amphiphilic BCPs, colloidal particles, and drug carriers.

The purpose of this study was to develop a poly(γ‐glutamic acid) (γ‐PGA)‐based hydrogel loaded with superoxide dismutase (SOD) to accelerate wound healing. First, γ‐PGA was modified with taurine (γ‐PGAS), and then the SOD‐loaded γ‐PGAS/γ‐PGA hydrogel (SOD‐PGAS/PGA‐H) was prepared by cross‐linking of ethylene glycol diglycidyl ether. The swelling behavior and water vapor transmission rate revealed that PGAS/PGA‐H could create a moist environment for wound surface. In vitro kinetics of SOD release showed that SOD released from PGAS/PGA‐H maintained high activity and SOD‐PGAS/PGA‐H effectively scavenged the superoxide anion. The results of our fibroblast proliferation experiments showed that PGAS/PGA‐H had good cytocompatibility. The effects of SOD‐PGAS/PGA‐H on wound healing were examined in a Type I diabetic rat model with full‐thickness wounds. Twenty‐one days after grafted to wounds, SOD‐PGAS/PGA‐H exhibited a higher rate of wound healing than control group and showed increased collagen deposition and epithelialization. SOD‐PGAS/PGA‐H seems to promote better wound healing and thus might be a promising candidate for wound healing management. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42033.

Polymer-protein core-corona particles can be used as multifunctional platforms in biological and medical applications. In this research, we prepared poly(2-hydroxyethyl methacrylate)-bovine serum albumin (PHEMA-BSA) core-corona particles by the ''grafting from'' method. In order to prepare the particles, activators generated by electron transfer for atom transfer radical polymerizations (AGET ATRP) of HEMA initiated by a BSA macroinitiator were performed. The polymerizations were conducted in the presence of ppm amounts of transition metal catalyst and ascorbic acid. Transmission electron microscopy, atomic force microscopy, dynamic light scattering and x-potential measurements were used to characterize the core-corona particles. The average size and x-potentials of the particles are strongly dependent on the amounts of BSA used in AGET ATRP. The secondary structure and bioactivity of the protein molecules in the coronae of the particles were studied. In vitro cytotoxicity assays and cell uptake assays indicate that the biohybrid particles are nontoxic and can be internalized into the cells. The polymer-protein core-corona particles will find applications in drug delivery and biomedical imaging.

Nanoparticles with protein coronae can be used as promising multifunctional platforms for nanomedicine due to the possibility to perform surface functionalization on protein molecules and the achievement of the biomedical...

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