Although gold is the subject of one of the most ancient themes of investigation in science, its renaissance now leads to an exponentially increasing number of publications, especially in the context of emerging nanoscience and nanotechnology with nanoparticles and self-assembled monolayers (SAMs). We will limit the present review to gold nanoparticles (AuNPs), also called gold colloids. AuNPs are the most stable metal nanoparticles, and they present fascinating aspects such as their assembly of multiple types involving materials science, the behavior of the individual particles, size-related electronic, magnetic and optical properties (quantum size effect), and their applications to catalysis and biology. Their promises are in these fields as well as in the bottom-up approach of nanotechnology, and they will be key materials and building block in the 21st century. Whereas the extraction of gold started in the 5th millennium B.C. near Varna (Bulgaria) and reached 10 tons per year in Egypt around 1200-1300 B.C. when the marvelous statue of Touthankamon was constructed, it is probable that “soluble” gold appeared around the 5th or 4th century B.C. in Egypt and China. In antiquity, materials were used in an ecological sense for both aesthetic and curative purposes. Colloidal gold was used to make ruby glass 293 Chem. Rev. 2004, 104, 293−346

Gold nanoparticles: assembly, supramolecular chemistry, quantum-size-related properties, and applications toward biology, catalysis, and nanotechnology.

Polydopamine and Its Derivative Materials: Synthesis and Promising Applications in Energy, Environmental, and Biomedical Fields

Approaches, Derivatives and Applications Vasilios Georgakilas,† Michal Otyepka,‡ Athanasios B. Bourlinos,‡ Vimlesh Chandra, Namdong Kim, K. Christian Kemp, Pavel Hobza,‡,§,⊥ Radek Zboril,*,‡ and Kwang S. Kim* †Institute of Materials Science, NCSR “Demokritos”, Ag. Paraskevi Attikis, 15310 Athens, Greece ‡Regional Centre of Advanced Technologies and Materials, Department of Physical Chemistry, Faculty of Science, Palacky University Olomouc, 17. listopadu 12, 771 46 Olomouc, Czech Republic Center for Superfunctional Materials, Department of Chemistry, Pohang University of Science and Technology, San 31, Hyojadong, Namgu, Pohang 790-784, Korea Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, v.v.i., Flemingovo naḿ. 2, 166 10 Prague 6, Czech Republic

Functionalization of Graphene: Covalent and Non-Covalent Approaches, Derivatives and Applications

Graphene has attracted tremendous research interest in recent years, owing to its exceptional properties. The scaled-up and reliable production of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), offers a wide range of possibilities to synthesize graphene-based functional materials for various applications. This critical review presents and discusses the current development of graphene-based composites. After introduction of the synthesis methods for graphene and its derivatives as well as their properties, we focus on the description of various methods to synthesize graphene-based composites, especially those with functional polymers and inorganic nanostructures. Particular emphasis is placed on strategies for the optimization of composite properties. Lastly, the advantages of graphene-based composites in applications such as the Li-ion batteries, supercapacitors, fuel cells, photovoltaic devices, photocatalysis, as well as Raman enhancement are described (279 references).

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Graphene-based composites

We review the present state of polymer nanocomposites research in which the fillers are single-wall or multiwall carbon nanotubes. By way of background we provide a brief synopsis about carbon nanotube materials and their suspensions. We summarize and critique various nanotube/polymer composite fabrication methods including solution mixing, melt mixing, and in situ polymerization with a particular emphasis on evaluating the dispersion state of the nanotubes. We discuss mechanical, electrical, rheological, thermal, and flammability properties separately and how these physical properties depend on the size, aspect ratio, loading, dispersion state, and alignment of nanotubes within polymer nanocomposites. Finally, we summarize the current challenges to and opportunities for efficiently translating the extraordinary properties of carbon nanotubes to polymer matrices in hopes of facilitating progress in this emerging area.

Polymer Nanocomposites Containing Carbon Nanotubes

The ability to manipulate and control the surface properties of nylons is of crucial importance to their widespread applications. In this work, surface-initiated atom-transfer radical polymerization (ATRP) is employed to tailor the functionality of the nylon membrane and pore surfaces in a well-controlled manner. A simple two-step method, involving the activation of surface amide groups with formaldehyde and the reaction of the resulting N-methylol polyamide with 2-bromoisobutyryl bromide, was first developed for the covalent immobilization of ATRP initiators on the nylon membrane and its pore surfaces. Functional polymer brushes of 2-hydroxyethyl methacrylate (HEMA) and poly(ethylene glycol)monomethacrylate (PEGMA) were prepared via surface-initiated ATRP from the nylon membranes. A kinetics study revealed that the chain growth from the membranes was consistent with a "controlled" process. The dormant chain ends of the grafted HEMA polymer (P(HEMA)) and PEGMA polymer (P(PEGMA)) on the nylon membranes could be reactivated for the consecutive surface-initiated ATRP to produce the corresponding nylon membranes functionalized by P(HEMA)-b-P(PEGMA) and P(PEGMA)-b-P(HEMA) diblock copolymer brushes. In addition, membranes with grafted P(HEMA) and P(PEGMA) brushes exhibited good resistance to protein adsorption and fouling under continuous-flow conditions.

Functionalization of nylon membranes via surface-initiated atom-transfer radical polymerization.

Silicone has been used for peritoneal dialysis (PD) catheters for several decades. However, bacteria, platelets, proteins, and other biomolecules tend to adhere to its hydrophobic surface, which may lead to PD outflow failure, serious infection, or even death. In this work, a cross-linked poly(poly(ethylene glycol) dimethacrylate) (P(PEGDMA)) polymer layer was covalently grafted on medical-grade silicone surface to improve its antibacterial and antifouling properties. The P(PEGDMA)-grafted silicone (Silicone-g-P(PEGDMA)) substrate reduced the adhesion of Staphylococcus aureus, Escherichia coli, and Staphylococcus epidermidis, as well as 3T3 fibroblast cells by ≥90%. The antibacterial and antifouling properties were preserved after the modified substrate was aged for 30 days in phosphate buffer saline. Further immobilization of a polysulfobetaine polymer, poly((2-(methacryloyloxy)ethyl)dimethyl-(3-sulfopropyl)ammonium hydroxide) (P(DMAPS)), on the Silicone-g-P(PEGDMA) substrate via thiol–ene click reaction...

Surface modification of silicone for biomedical applications requiring long-term antibacterial, antifouling, and hemocompatible properties.

Superparamagnetic Fe3O4 particles are successfully encapsulated inside polypyrrole (PPY) via emulsion polymerization using polyvinyl alcohol as a surfactant. The thus-obtained PPY-Fe3O4 nanoparticles have distinct spherical shape and size (80–100 nm in diameter) and are superparamagnetic with high magnetization values and good electrical conductivities. By varying the starting Fe3O4 : pyrrole monomer mass ratio, nanoparticles with varying Fe3O4 content can be synthesized. These nanoparticles are also cyto-compatible, and due to the electrically conducting PPY they display enhanced specific power absorption rates on the basis of per unit weight of Fe as compared to the seed Fe3O4 particles. The surfaces of these nanoparticles can be further functionalized with cell-targeting molecules such as folic acid. The potential of using folic acid-functionalized PPY-Fe3O4 nanoparticles in cancer cell targeting was investigated and it was observed that the uptake of these nanoparticles by MCF-7 breast cancer cells is significantly enhanced as compared to non-functionalized ones. Such nanoparticles with cancer cell targeting capability and enhanced specific power absorption rates hold great promise for use in the intracellular hyperthermia treatment of cancer tumors.

Synthesis and functionalization of polypyrrole-Fe3O4 nanoparticles for applications in biomedicine

Covalent immobilization of glucose oxidase on microporous membranes prepared from poly(vinylidene fluoride) with grafted poly(acrylic acid) side chains

Pseudo-Block Copolymer Based on Star-Shaped Poly(N-isopropylacrylamide) with a β-Cyclodextrin Core and Guest-Bearing PEG: Controlling Thermoresponsivity through Supramolecular Self-Assembly

En-Tang Kang

Papers

Functionalization of nylon membranes via surface-initiated atom-transfer radical polymerization.

Surface modification of silicone for biomedical applications requiring long-term antibacterial, antifouling, and hemocompatible properties.

Synthesis and functionalization of polypyrrole-Fe3O4 nanoparticles for applications in biomedicine

Covalent immobilization of glucose oxidase on microporous membranes prepared from poly(vinylidene fluoride) with grafted poly(acrylic acid) side chains

Pseudo-Block Copolymer Based on Star-Shaped Poly(N-isopropylacrylamide) with a β-Cyclodextrin Core and Guest-Bearing PEG: Controlling Thermoresponsivity through Supramolecular Self-Assembly