0,1,2,3D nanostructures, types of bulk nanostructured materials, and drug nanocrystals: An overview

Functional materials are required to meet the needs of society, such as environmental protection, energy storage and conversion, integrated product production, biological and medical processing. bulk nanostructured materials are a research concept that combines nanotechnology with other research fields such as supramolecular chemistry, materials science, and life science to develop logically functional materials from nanodevices. In this review article, nanostructures are synthetized by different methods based on the types and nature of the nanomaterials. In a broad sense "top-down" and "bottom-up" are the two foremost methods to synthesize nanomaterials. In top-down method bulk materials have been reduced to nanomaterials, and in case of bottom-up method, the nanomaterials are synthesized from elementary level. The different methods which are being used to synthesize nanomaterials are chemical vapor deposition method, thermal decomposition, hydrothermal synthesis, solvothermal method, pulsed laser ablation, templating method, combustion method, microwave synthesis, gas phase method, and conventional Sol-Gel method. We also briefly discuss the various physical and chemical methods for producing nanomaterials. We then discuss the applications of functional materials in many areas such as energy storage, supercapacitors, sensors, wastewater treatment, and other biological applications such as drug delivery and drug nanocrystals. Finally, future challenges in materials nanoarchitecture and concepts for further development of functional nanomaterials are briefly discussed.

Magnetron Sputtering as a Versatile Tool for Precise Synthesis of Hybrid Iron Oxide-Graphite Nanomaterial for Electrochemical Applications

Iron oxide nanomaterials are promising candidates for various electrochemical applications. However, under operating conditions high electric resistance is still limiting performance and lifetime. By incorporating the electronically conductive carbon into a nanohybrid, performance may be increased and degeneration due to delamination may be prevented, eliminating major drawbacks. For future applications, performance is an important key, but also cost-effective manufacturing suitable for scale-up must be developed. A possible approach that shows good potential for up-scale is magnetron sputtering. In this study, a systematic investigation of iron oxides produced by RF magnetron sputtering was carried out, with a focus on establishing correlations between process parameters and resulting structural properties. It was observed that increasing the process pressure was favourable with regard to porosity. Over the entire pressure range investigated, the product consisted of low-crystalline Fe3O4, as well as Fe2O3 as a minor phase. During sputtering, a high degree of graphitisation of carbon was achieved, allowing for sufficient electronic conductivity. By means of a new alternating magnetron sputtering process, highly homogeneous salt-and-pepper-type arrangements of both nanodomains, iron oxide and carbon were achieved. This nano-containment of the redox-active species in a highly conductive carbon domain improves the material's overall conductivity, while simultaneously increasing the electrochemical stability by 44%, as confirmed by cyclic voltammetry.

Understanding fluorometric interactions in ion-responsive sustainable polymer nanocomposite scaffolds

The fluorescent colour in biodegradable and biocompatible flexible polymer nanocomposite gels was modulated in order to gain insight into the interfacial interactions of functional scaffolds with metal ions. The hybrid nanomaterials were introduced into the polymer matrix to obtain mechanically robust porous morphologies where the intrinsic luminescence matrix was found to critically enhance the threshold of the visual detection limits. The quenching of fluorescence intensity has been predominantly attributed to the interactions of functional receptors of luminescent nanofillers with respect to the chromophores of the fluorescent matrix. The chromium ion is selected to understand the change in fluorescence intensity of the nanocomposite gel with the degree of metal ion adsorption. The number of functional nanomaterials loaded into the matrix and the luminescence nature of the base polymer are varied with the purpose of gaining insight into the remote sensing mechanism of the colorimetric fluorescent probe.

Microphase separation in oriented polymeric chains at the surface of nanomaterials during nanofiber formation

The presence of low-dimensional functional nanofillers during the formation of morphological phase boundaries in polymeric nanofibers by electrospinning was highlighted in this study. PAN and TPU were both selected with differential viscosities to understand the phase-segregated internal supramolecular structures on functional surfaces of different length scales. The low-dimensional carbon nanofillers displayed a significant role in the topological orientation of the polymeric chains in TPU due to the presence of hard and soft segments in the geometry of TPU. The nano-hybrid shish-kebab-type microphase separation was observed on 1D nanofillers, whereas the anisotropic hierarchical microdomains were formed in the presence of 0D nanofillers. The 2D functional surface produced highly folded nanoscale lamellae by molecular interactions with polymeric chains. By combining different dimensional nanofillers, the hybrid 1D-2D networks created multifaceted structural hierarchies with epitaxial growth on the planar surface and shish-kebab geometry on the 1D functional backbone. Our study has demonstrated the significance of the configuration of nanoscale functional surfaces on the texture of polymeric chain assemblies during electrospinning for controlled flexible scaffolds.

Mitoferrin-1 is Involved in the Progression of Alzheimer's Disease Through Targeting Mitochondrial Iron Metabolism in a Caenorhabditis elegans Model of Alzheimer's Disease

In mammals, mitoferrin-1 and mitoferrin-2, two homologous proteins of the mitochondrial solute carrier family are required for iron delivery into mitochondria. However, there is only one kind, called W02B12 (mitoferrin-1 or mfn-1), in Caenorhabditis elegans and its regulatory mechanism is unknown. In this study, we used C. elegans strains CL2006 and GMC101 as models to investigate what role mitoferrin-1 played in Alzheimer's disease (AD). We found that knockdown of mitoferrin-1 by feeding-RNAi treatment extended lifespans of both strains of C. elegans. In addition, it reduced the paralysis rate in the GMC101 strain. These results suggest that mitoferrin-1 may be involved in the progression of Alzheimer's disease. Knockdown of mitoferrin-1 was seen to disturb mitochondrial morphology in the CB5600 strain. We tested whether knockdown of mitoferrin-1 could influence mitochondrial metabolism. Analysis of mitochondrial iron metabolism and mitochondrial ROS showed that knockdown of mitoferrin-1 could reduce mitochondrial iron content and reduce the level of mitochondrial ROS in the CL2006 and GMC101 strains. These results confirm that knockdown of mitoferrin-1 can slow the progress of disease in Alzheimer model of C. elegans and suggest that mitoferrin-1 plays a major role in mediating mitochondrial iron metabolism in this process.

Effect of Reinforcement at Length Scale for Polyurethane Cellular Scaffolds by Supramolecular Assemblies

This study is aimed to represent the role of carbonaceous nanofillers to reinforce the commercially available polyurethane porous structure. The effect of dimensionality of fillers to anchor the construction of stable three-dimensional (3D) cellular architectures has been highlighted. The cellular frameworks of commercially available thermoplastic polyurethane (TPU) have been fabricated through the thermoreversible supramolecular self-assembly route. It was established that the minimum shrinkage of TPU lattice structures occurred when the solid-state network is strengthened by the topologically engineered 3D hierarchical nanofillers, where the amount of reinforcement was found to play a critical role. It has been established by series of structure-property correlations that reinforcing the cellular structure to endure the capillary stress is equally effective as supercritical drying for producing low-density porous morphologies. The removal of liquid phase from gel is as important as the presence of 3D fillers in the matrix for reinforcing the cellular structures when replacing the solvent phase with air to generate a two-phase solid-gas engineered morphology. The insight into the polyurethane network structure revealed that the dimensionality, amount, and distribution of fillers in the matrix are critical for reinforcing the cellular scaffolds in solid gel without any cross-linking.