Switchable and Obedient Interfacial Properties That Grant New Biomedical Applications.

Toward imitating the natural smartness and responsivity of biological systems, surface interfacial properties are considered to be responsive and tunable if they show a reactive behavior to an environmental stimulus. This is still quite different from many contemporary biomaterials that lack responsiveness to interact with blood and different body tissues in a physiological manner. Meanwhile it is possible to even go one step further from responsiveness to dual-mode switchability and explore "switchable" or "reversible" responses of synthetic materials.

Cyclic Redox-Mediated Switching of Surface Properties of Thiolated Polysaccharide Multilayers and Its Effect on Fibroblast Adhesion.

Advanced technologies for controlled cell adhesion and detachment in novel biointerface designs profit from stimuli-responsive systems that are able to react to their environment. Here, a multilayer system made of thiolated chitosan and thiolated chondroitin sulfate was constructed, with the potential of switchable inter- and intramolecular thiol/disulfide interactions representing a redox-sensitive nanoplatform. Owing to the formation and cleavage of inherent disulfide bonds by oxidation and reduction, surface properties of the multilayer can be controlled toward protein adsorption/desorption and cell adhesion in a reversible manner.

ZnO Q-dots as a potent therapeutic nanomedicine for in vitro cytotoxicity evaluation of mouth KB44, breast MCF7, colon HT29 and HeLa cancer cell lines, mouse ear swelling tests in vivo and its side effects using the animal model.

Nanoformulations derived from fine porous ZnO quantum dot nanoparticles (QD NPs) can offer strong potential medical applications; especially in cancer therapy. ZnO QD NPs was synthesized by sol-gel hydrothermal process, fast cold quenching and further smart surface functionalization methods to obtain ultrasmall size (1-4 nm) NPs. ZnO nanopolymer, a wetting agent, PEG co-solvent and water/oil emulsion stabilizer were considered in our nanofluid formulation.

Stimuli-Responsive Multilayers Based on Thiolated Polysaccharides That Affect Fibroblast Cell Adhesion.

Control of the biomaterial properties through stimuli-responsive polymeric platforms has become an essential technique in recent biomedical applications. A multilayer system of thiolated chitosan (t-Chi) and thiolated chondroitin sulfate (t-CS), consisting of five double layers ([t-Chi/t-CS]), was fabricated here by applying a layer-by-layer coating strategy. To represent a novel class of chemically tunable nanostructures, the ability to cross-link pendant thiol groups was tested by a rise from pH 4 during layer formation to pH 9.

Synthesis of thiolated polysaccharides for formation of polyelectrolyte multilayers with improved cellular adhesion.

Intrinsic cross-linking is not only useful for increasing stability, but also for tailoring mechanical properties of polyelectrolyte multilayers (PEM) on implants and tissue engineering scaffolds. Here, a novel route for synthesizing thiolated chitosan (t-Chi) based on the application of 3,3'-dithiodipropionic acid was applied, while thiolated chondroitin sulfate (t-CS) was conjugated by 3,3'-dithiobis (propanoic hydrazide). Both products were subsequently reduced to obtain the free thiols.

A synthetic garden of state of the art natural protein nanoarchitectures dispersed in nanofluids.

As a significant discovery in the 20th century, carbon nanotubes are attracting particular attention in many unique fields such as electronics, catalysts, hydrogen storage composites, gas sensors, drug delivery, medical diagnostics, therapeutics and nanofluids. In this project, we focus on self-assembled synthetic special natural protein alpha-lactalbumin nanotubes with different (straight, waved, coiled, regularly bent, branched, beaded) shapes, nanospherical particles, nanorods, nanowires, nanopores, polyhedral (hexagonal network, spherical, cubic) nanostructures, nanochannels, nanofibers, nanosheets, nanoleaves, nanowave branched structures, nanobeads, nanoflowers, nanocapsules, novel nano-hybrids consisting of tubes and rods (new core-shell), nanocrystal shapes, apiary or cobweb, branched nanotubes with Y-junctions, nano membrane structures, nano sweep symmetrical shape, nano sponge structures, nano helical homogeneous structures and nano perpendicular and horizontal stable hollow single-walled natural protein nanotubes (NPNTs). These were successfully synthesized by the chemical hydrolysis sol--gel method and partial biochemical enzymatic hydrolysis by cleavage sites (Asp-X and Glu-X) of the milk protein a-lactalbumin by using various organic surfactants, pH controller functions and divalent metallic salt ions as a binding site or ions ligand formation between two bio-based building blocks to form remarkable various new morphologies in appearance of nanoemulsions and clear green nanofluids, for application in the diet nutrition food science and pharmaceutical industry.