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Background: Treatment for lower respiratory tract infection caused by multidrug-resistant organisms (MDRO) are often limited. This study explored the activity of different metal nanoparticles against several respiratory pathogens including MDROs. Methods: Clinical isolates of carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Klebsiella pneumoniae (CRKP), Pseudomonas aeruginosa, Haemophilus influenzae, methicillin-resistant Staphylococcus aureus (MRSA), and Streptococcus pneumoniae were tested for in vitro susceptibilities to various antibiotics and nanoparticles. Minimum inhibitory concentrations (MICs) of silver-nanoparticle (Ag-NP), selenium-nanoparticle (Se-NP), and three composites solutions ND50, NK99, and TPNT1 (contained 5 ppm Ag-NP, 60 ppm ZnO-nanoparticle, and different concentrations of gold-nanoparticle or ClO2) were determined by broth microdilution method. Results: Fifty isolates of each bacterial species listed above were tested. Ag-NP showed lower MICs to all species than Se-NP. The MIC50s of Ag-NP for CRAB, CRKP, P. aeruginosa, and H. influenzae were 50 ppm and 50 ppm. Among CRAB, CRKP and P. aeruginosa, the MIC50s of ND50, NK99, and TPNT1 for CRAB were the lowest (1/8 dilution, 1/8 dilution, and 1/8 dilution, respectively), and those for CRKP (>1/2 dilution, 1/2 dilution, and 1/2 dilution, respectively) were the highest. Both MRSA and S. pneumoniae showed high MIC50s to ND50, NK99, and TPNT1. Conclusions: Metal nanoparticles had good in vitro activity against Gram-negative bacteria. They might be suitable to be prepared as environmental disinfectants or inhaled agents to inhibit the growth of MDR Gram-negative colonizers in the lower respiratory tracts of patients with chronic lung diseases.

The application and extraordinary properties of ZnO nanowire in emerging nanoelectronics is discussed. An overview of basic nanowire synthesis and fundamental electrical properties based on field-effect transistor configuration is also presented.

Highly ordered anodic titanium oxide (ATO) TiO2nanotube film has been synthesized via a typical two-step anodization method. Following a reductive doping approach, metallic materials (copper and nickel) can be efficiently electrodeposited into the nanotubes. This versatile process yields reproducible tubular structures in ATO membranes, because of the conductive nature of crystallized TiO2, yielding promising potential for nanotemplate applications. In this paper, we present a dye-sensitized solar cell constructed by employing such ATO films. It is observed that the reductive doping treatment can also enhance the solar cell’s short current density and fill factor, resulting in an improved energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Highly ordered anodic titanium oxide (ATO) TiO2nanotube film has been synthesized via a typical two-step anodization method. Following a reductive doping approach, metallic materials (copper and nickel) can be efficiently electrodeposited into the nanotubes. This versatile process yields reproducible tubular structures in ATO membranes, because of the conductive nature of crystallized TiO2, yielding promising potential for nanotemplate applications. In this paper, we present a dye-sensitized solar cell constructed by employing such ATO films. It is observed that the reductive doping treatment can also enhance the solar cell’s short current density and fill factor, resulting in an improved energy conversion efficiency. [ABSTRACT FROM AUTHOR]

Quasione-dimensional Ga2O3 nanowires are synthesized via catalytic chemical vapor deposition method. Their morphology and crystal structure are characterized by electron microscopy and x-ray diffraction techniques, and their optical property is studied by photoluminescence measurement. To develop their future application in nanoelectronic devices, the as-grown Ga2O3 nanowires are doped with zinc to increase its carrier concentration and subsequently fabricated into field-effect transistors. Electron transport measurements show that the doped nanowires exhibit p-type semiconducting behavior with a significant enhancement of conductivity. [ABSTRACT FROM AUTHOR]

Single crystal ZnO nanowires are synthesized and configured as field-effect transistors. Photoluminescence and photoconductivity measurements show defect-related deep electronic states giving rise to green-red emission and absorption. Photocurrent temporal response shows that current decay time is significantly prolonged in vacuum due to a slower oxygen chemisorption process. The photoconductivity of ZnO nanowires is strongly polarization dependent. Collectively, these results demonstrate that ZnO nanowire is a remarkable optoelectronic material for nanoscale device applications. [ABSTRACT FROM AUTHOR]

A correction to the article "High-performance ZnO nanowire field effect transistors" that was published in the 2006 issue is presented.