Nanostructure, key to property alteration, has been widely diverse by using two-dimensional nanoparticle in different stages of polymerization. Molecular level self-assembly starting from nanoscale 2-D molecular sheet to optically observable microscale crystallite has been unraveled stepwise for thermoplastic elastomer for the first time. The nature of self-assembly can be tuned by judicious choice of polymerization procedure in the presence of organically modified nanoclay. The effect of modulated nanostructure and self-assembly has been explored for the unusual property enhancement including electronic, thermal, mechanical, barrier, and biological (genotoxicity). Both the stiffness and toughness increase in nano-biohybrid without any trade-off. The unique splintering phenomenon and its variation under a dynamic frequency have been investigated by changing the synthesizing route of nanohybrids using a fixed concentration of nanoparticle. For understanding the controlled cellular responses to the implant new hybrid materials, cell adhesion and detailed genotoxicity reveal total biological recognition of the developed nano-biohybrids.

We have focused on the generation of various nanostructures of poly(3-caprolactone) (PCL) using surface modified layered silicate. The improved and diverse mechanical, thermal and surface properties have been explored depending upon the nanostructure of the nanohybrids. The incorporation of drug into those nanohybrids further alters the nanostructure and subsequent properties. The rate of biodegradation has been studied in detail, with plausible mechanisms in different enzyme media being suggested, their specificity and the tunability of the biodegradation rate was demonstrated, followed by their optimization. The scaffolds of PCL and its nanohybrids with and without drugs have been prepared through electrospinning to control the dimensions of the nanofibers and their controlled degradation. The in-depth studies of the biocompatibility in terms of cell adhesion, genotoxicity and hemocompatibility have been performed to verify the suitability of the nanohybrids for potential biomedical applications. The biocompatibility of the nanohybrids at the gene level has been tested by the subcellular localization of an important regulator of pro-apoptotic signalling cascade, HIPK2 in human epithelial cells, demonstrating the attuned nature of the particles under study within the biological system. The blood compatibilities of the pure PCL and its nanohybrids were studied by platelet aggregation, platelet adhesion, and in vitro hemolysis assay, elucidating the excellent hemocompatibility of the novel nanohybrids. Biocompatible and hemocompatible nanohybrids have been testified for drug delivery and show sustained and controlled release of anti-cancer drugs (dexamethasone) in the presence of two dimensional disc-like nanoparticles. Hence, the developed nanohybrids are a potential biomaterial, suitable for tissue engineering and drug delivery.

Our findings suggest that aged animals fail to counteract hypertensive condition resulting in upregulation of miR-122 and subsequently Bach-1, leading to decreased levels of Ho-1 and an increase in DNA damage and tissue inflammation. Together, these lead to increased collagen deposition thereby causing reduced vascular density and increased renal resistive index.

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b S Supporting Information ' INTRODUCTION Self-assembly in polymers is being extensively revealed for tailoring and fabricating the structures in the nanoscale dimensions. 1À5 Polymeric self-assembly has numerous advantages over conventional materials due to their explicit feature of assembling in highly ordered lamellar, spherical, and networked morphologies; as a matter of fact, these materials are having a superior thermo-mechanical property, which leads to metastable structure. 6À11 In recent years, high performance self-assembled thermoplastic polyurethane have been extensively used in shape memory materials, molecular recognition, tissue engineering, and sustained drug delivery applications. 12À15 The thermodynamic structural incongruity of hydrogen bonded hard and soft segmented domains in a regular fashion lead to unusual selfassembled patterning in thermoplastic polyurethanes. 16,17 The incorporation of nanoparticles as a potential reinforcing agent in the matrix of self-assembled polyurethanes produces the unparallel combinations of strength, stiffness, and toughness in these novel nanohybrids. 18À20 Wang and Pinnavaia were the foremost to observe the dramatic enhancement in the tensile strength and modulus by the incorporation of these 2-D nanoparticles in the thermoplastic polyurethane matrix. 21 Subsequently, polyurethane nanohybrids have been explored due to interactions of 2-D nanoclay tactoids with the alternating assembly of hard and soft segments. Moreover, the physiochemical and biological properties of polymeric self-assemblies can be tuned by varying chemical structure and the constituents present in the polymer backbone or by the presence of nanofillers. 22À25 Nanofiller supported polymeric matrix may have the potential for cellular growth for tissue engineering. Recently, we have reported molecular level self-assembly starting from nanoscale organization to optically observable microscale crystallite for thermoplastics leading to patterned structures. 26 The tunability of selfassembled structure is still a challenge which might be realistic either by incorporating new chemical entity or by dispersing a second phase in the form of filler. The effect of modulated nanostructure and self-assembly has been unraveled for the unusual electronic, thermal, mechanical, barrier, and biological property enhancement. 27 The controlled cellular responses have been observed in the gene level through cell adhesion by monitoring the localization of HIPK2 protein inside the cell. 28 A number of kinases are activated as a reaction to DNA damage or genotoxic stress. A member of the serine/ threonine kinase family, HIPK2, is activated and stabilized upon DNA damage and direct the cell toward p53-dependent apoptosis or ABSTRACT: Novel polyurethanes have been synthesized using aliphatic diisocyanate and aromatic chain extenders with varying spacer length. Nanohybrids of those polyurethanes have been prepared using two-dimensional surface modified nanoclay by dispersing it in poly-ol followed by prepolymerization ...