This review deals with different aspects of hydrophobicity at nanostructured surfaces. Theoretical and geometric effects as well as those of surface feature geometry on hydrophobicity are explored in this article. This review includes surface modification methods used to change surface hydrophobicity and effect on adhesion of cells as nano substrate. A small chapter is devoted to hydrophobicity at self-assembled monolayers as a special type of nanostructured surface. To the different models describing hydrophobicity is devoted one up to dated chapter. Calculation methods including quantum, density functional theory, and molecular modeling bring novel perspectives to the study of hydrophobicity at nanostructured surfaces.

Diabetes mellitus represents one of the most widespread diseases in civilization nowadays. Since the costs for treating and diagnosing of diabetes represent several billions of dollars per year, a cheap, fast, and simple sensor for diabetes diagnosis is needed. Electrochemical insulin sensors can be considered as a novel approach for diabetes diagnosis. In this study, carbon electrode with electrodeposited NiO nanoparticles was selected as a suitable electrode material for insulin determination. The morphology and surface composition were studied by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) spectroscopy, and X-ray photoelectron spectroscopy (XPS). For a better understanding of insulin determination on NiO-modified electrodes, the mechanism of electrochemical reaction and the kinetic parameters were studied. They were calculated from both voltammetric and amperometric measurements. The modified carbon electrode displayed a wide linear range from 600 nM to 10 µM, a low limit of detection of 19.6 nM, and a high sensitivity of 7.06 µA/µM. The electrodes were stable for 30 cycles and were able to detect insulin even in bovine blood serum. Additionally, the temperature stability of this electrode and its storage conditions were studied with appropriate outcomes. The above results show the high promise of this electrode for detecting insulin in clinical samples.

Iron-based substrates with polyethylene glycol coating were prepared as possible materials for biodegradable orthopedic implants. Biodegradable materials that provide mechanical support of the diseased tissue at the time of implanting and then disappear gradually during the healing process are sometimes favored instead of permanent implants. The implant degradation rate should match the time of the tissue regrowth. In this work, the degradation behavior of iron-based foams was studied electrochemically during immersion tests in Hanks’ solution. The corrosion rate of the polyethylene glycol-coated samples increased and the corrosion potential shifted to more negative values. This indicates an enhanced degradation rate as compared to the uncoated material, fulfilling the goal of being able to tune the degradation rate. It is the interfacial interaction between the hydrophilic polymer layer and the iron surface that is responsible for the enhanced oxidation rate of iron.