Here, we report the scalable synthesis and characterization of low-density, porous, three-dimensional (3D) solids consisting of two-dimensional (2D) hexagonal boron nitride (h-BN) sheets. The structures are synthesized using bottom-up, low-temperature (∼300 °C), solid-state reaction of melamine and boric acid giving rise to porous and mechanically stable interconnected h-BN layers. A layered 3D structure forms due to the formation of h-BN, and significant improvements in the mechanical properties were observed over a range of temperatures, compared to graphene oxide or reduced graphene oxide foams. A theoretical model based on Density Functional Theory (DFT) is proposed for the formation of h-BN architectures. The material shows excellent, recyclable absorption capacity for oils and organic solvents.

Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine. Here, we have synthesized zinc oxide (ZnO) nanorods using zinc acetate and hexamethylenetetramine as precursors followed by characterizing using X-ray diffraction, fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy. The growth of synthesized zinc oxide nanorods was found to be very close to its hexagonal nature, which is confirmed by X-ray diffraction. The nanorod was grown perpendicular to the long-axis and grew along the [001] direction, which is the nature of ZnO growth. The morphology of synthesized ZnO nanorods from the individual crystalline nucleus was confirmed by scanning and transmission electron microscopy. The length of the nanorod was estimated to be around 21 nm in diameter and 50 nm in length. Our toxicology studies showed that synthesized ZnO nanorods exposure on hela cells has no significant induction of oxidative stress or cell death even in higher concentration (10 μg/ml). The results suggest that ZnO nanorods might be a safer nanomaterial for biological applications.Keywords: Zinc oxide [ZnO]; Nanorods; XRD; SEM & TEM; Cytotoxicity Citation: R. Gopikrishnan, K. Zhang, P. Ravichandran, S. Baluchamy, V. Ramesh, S. Biradar, P. Ramesh, J. Pradhan, J. C. Hall, A. K. Pradhan and G. T. Ramesh, "Synthesis, characterization and biocompatibility studies of zinc oxide (ZnO) nanorods for biomedical application", Nano-Micro Lett. 2, 31-36 (2010). doi: 10.5101/nml.v2i1.p31-36 Nanotechnology has extraordinary potential to change our lives by improving existing products and enabling new ones. It facilitates the development of new materials in the 1a100 nm range, comparable to the size range of biological molecules and structures [1]. Nanomaterials are very attractive materials for the manipulation, sensing and detection of biological structures and systems [2]. The principal factors which make nanomaterials different from their bulk counterparts include an increase in their relative surface area and quantum effects, which affect their physical and chemical properties [2]. This is due to the large surface area-to-volume ratio of nanoparticles, which increases surface free energy to a point that is comparable to their lattice energy. For example, a particle of 30 nm size has 5% of its atoms on its surface compared to 50% of the atoms on the surface of a 3 nm particle [3]. The altered properties of nanomaterials, and their size similarity to naturally occurring cell structures, will allow them to interact readily with bio molecules and potentially affect the cellular responses in a dynamic and selective manner. Materials that exploit these characteristics are becoming increasingly attractive for use in novel biomedical applications.Nano structured materials exhibit unique properties related to their size, and are used in an array of applications such as optoelectronics, nano/microelectronics, sensors, transducers, cosmetics as w...

The synthesis of nanoparticles and their functionalization to effectively utilize them in biological applications including drug delivery is currently a challenge. Calcium carbonate among many other inorganic nanosized particles offers promising results for such applications. We have synthesized calcium carbonate nanoparticles using polymer mediated growth technique, where one of the ions bound within polymer matrix and the other diffuses and reacts to form desired compound. The synthesized nanoparticles are characterized using X-ray diffraction, Scanning Electron Microscopy and spectroscopic techniques such as Fourier-Transform Infra-red spectroscopy and UV-Vis spectroscopy. The diameter of the calcium carbonate nanoparticles is estimated to be 39.8 nm and their biocompatibility studies showed no significant induction of oxidative stress or cell death even at higher concentrations (50 microg) upon exposure to HeLa and LE cells. Here, we report that the synthesized calcium carbonate nanosized particles using polymer mediated growth technique are biocompatible and can be safely used for biomedical applications.

Hydroxyapatite (HAp) nano-ceramic powder was synthesized successfully via microwave irradiation technique.

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