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Bismuth oxide is an important bismuth compound having applications in electronics, photo-catalysis and medicine. At the nanoscale, bismuth oxide experiences a variety of new physico-chemical properties because of its increased surface to volume ratio leading to potentially new applications. In this manuscript, we report for the very first time the synthesis of bismuth oxide (Bi 2 O 3 ) nano-flakes by pulsed laser ablation in liquids without any external assistance (no acoustic, electric field, or magnetic field). The synthesis was performed by irradiating, pure bismuth needles immerged in de-ionized water, at very high fluence ∼160 J cm −2 in order to be highly selective and only promote the growth of two-dimensional structures. The x - and y -dimensions of the flakes were around 1 μm in size while their thickness was 47.0 ± 12.7 nm as confirmed by AFM analysis. The flakes were confirmed to be α- and γ-Bi 2 O 3 by SAED and Raman spectroscopy. By using this mixture of flakes, we demonstrated that the nanostructures can be used as antimicrobial agents, achieving a complete inhibition of Gram positive (MSRA) and Gram negative bacteria (MDR-EC) at low concentration, ∼50 ppm. 

The burgeoning field of nanotechnology aims to create and deploy nanoscale structures, devices, and systems with novel, size-dependent properties and functions. The nanotechnology revolution has sparked radically new technologies and strategies across all scientific disciplines, with nanotechnology now applied to virtually every area of research and development in the US and globally. NanoFlorida was founded to create a forum for scientific exchange, promote networking among nanoscientists, encourage collaborative research efforts across institutions, forge strong industry-academia partnerships in nanoscience, and showcase the contributions of students and trainees in nanotechnology fields. The 2019 NanoFlorida International Conference expanded this vision to emphasize national and international participation, with a focus on advances made in translating nanotechnology. This review highlights notable research in the areas of engineering especially in optics, photonics and plasmonics and electronics; biomedical devices, nano-biotechnology, nanotherapeutics including both experimental nanotherapies and nanovaccines; nano-diagnostics and -theranostics; nano-enabled drug discovery platforms; tissue engineering, bioprinting, and environmental nanotechnology, as well as challenges and directions for future research. 

Bacterial infection of implanted biomaterials is a serious problem that increases health care costs and negatively affects a considerable fraction of orthopedic procedures. In this field, magnesium oxide nanoparticles (MgO NPs) have emerged as a promising material to combat bacterial infection while maintaining or improving bone cell functions. Here, MgO NPs were electrophoretically deposited onto poly‐L‐lactic acid (PLLA) sheets to achieve a coating of highly exposed MgO NPs that directly influenced cell‐substrate interactions at short time scales. Samples were characterized for their surface chemistry, crystal structure, roughness, wettability, degradation characteristics, and their ability to support the growth of human fibroblasts and osteoblasts, as well as their resistance to colonization byStaphylococcus aureus,Staphylococcus epidermidis, andPseudomonas aeruginosa. In general, increasing the applied voltage during deposition increased the surface coverage of the coating and significantly decreased the colonization of all three bacterial strains (up to a 90% reduction). Furthermore,S. aureuscells that did attach onto substrates prepared at high voltages exhibited trademark signs of membrane damage and cell death. Importantly, MTS cell viability assays indicated that osteoblast adhesion increased with increasing deposition voltage, while fibroblast adhesion exhibited the opposite trend. Thus, although requiring more studies, this research provides the first evidence that MgO NP coatings prepared at relatively high voltages (120–150 V) may have the ability to resist bacterial colonization, promote bone cell attachment, and curb fibrous capsule formation. Therefore, it is recommended that this technology be further investigated and developed for numerous orthopedic applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 3136–3147, 2017.