Biotemplated synthesis of functional nanomaterials has received increasing attention for applications in energy, catalysis, bioimaging, and other technologies. This approach is justified by the unique abilities of biological systems to guide sophisticated assembly and organization of molecules and materials into distinctive nanoscale morphologies that exhibit physicochemical properties highly desirable for specific purposes. Here, we present a high-performance, flexible nanogenerator using anisotropic BaTiO3 (BTO) nanocrystals synthesized on an M13 viral template through the genetically programmed self-assembly of metal ion precursors. The filamentous viral template realizes the formation of a highly entangled, well-dispersed network of anisotropic BTO nanostructures with high crystallinity and piezoelectricity. Even without the use of additional structural stabilizers, our virus-enabled flexible nanogenerator exhibits a high electrical output up to ∼300 nA and ∼6 V, indicating the importance of nanoscale structures for device performances. This study shows the biotemplating approach as a facile method to design and fabricate nanoscale materials particularly suitable for flexible energy harvesting applications.

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Influenza is a serious public health concern worldwide, as it causes significant morbidity and mortality. The emergence of drug-resistant viral strains requires new approaches for the treatment of influenza. In this study, Rubus coreanus seed (RCS) that is left over from the production of wine or juice was found to show antiviral activities against influenza type A and B viruses. Using the time-of-addition plaque assay, viral replication was almost completely abolished by simultaneous treatment with the RCS fraction of less than a 1-kDa molecular weight (RCSF1). One of the polyphenols derived from RCSF1, gallic acid (GA), identified by liquid chromatography-tandem mass spectrometry, showed inhibitory effects against both influenza type A and B viruses, albeit at relatively high concentrations. RCSF1 was bound to hemagglutinin protein, inhibited hemagglutination significantly and disrupted viral particles, whereas GA was found to only disrupt the viral particles by using transmission electron microscopy. In BALB/c mice infected with influenza virus, oral administration of RCSF1 significantly improved the survival rate and reduced the viral titers in the lungs. Our results demonstrate that RCSF1 and GA show potent and broad antiviral activity against influenza A and B type viruses and are promising sources of agents that target virus particles.

Hydrogen was produced by methanol decomposition over cold-rolled foils of intermetallic compound Ni 3 Al which is known as an excellent high-temperature structural material. We found high catalytic activity and selectivity for methanol decomposition in flat cold-rolled Ni 3 Al foils. The catalytic activity was enhanced above 713 K by the spontaneous formation of fine Ni particles dispersed on carbon nanofibers during the reaction, resulting in high catalytic performance. The results demonstrate that the Ni 3 Al foils can be used both as catalyst precursors and as structural materials of microreactors for hydrogen production.

Interpretations of the interactions of nanocarriers with biological cells are often complicated by complex synthesis of materials, broad size distribution, and heterogeneous surface chemistry. Herein, the major capsid proteins of an icosahedral T7 phage (55 nm in diameter) are genetically engineered to display a gold-binding peptide and a prostate cancer cell-binding peptide in a tandem sequence. The genetically modified phage attracts gold nanoparticles (AuNPs) to form a cluster of gold nanoparticles (about 70 nanoparticles per phage). The cluster of AuNPs maintains cell-targeting functionality and exhibits excellent dispersion stability in serum. Under a very low light irradiation (60 mW cm(-2)), only targeted AuNP clusters kill the prostate cancer cells in minutes (not in other cell types), whereas neither nontargeted AuNP clusters nor citrate-stabilized AuNPs cause any significant cell death. The result suggests that the prostate cancer cell-targeted clusters of AuNPs are targeted to only prostate cancer cells and, when illuminated, generate local heating to more efficiently and selectively kill the targeted cancer cells. Our strategy can be generalized to target other types of cells and assemble other kinds of nanoparticles for a broad range of applications.