S. Noori, J. Khalil-Allafi,
Volume 12, Issue 2 (6-2015)
Abstract
The effect of anodic oxidation of a NiTi shape memory alloy in sulfuric acid electrolyte on its surface
characteristics was studied. Surface roughness was measured by roughness tester. Surface morphology was studied
using optical microscopy (OM) and scanning electron microscopy (SEM). Corrosion behavior was specified by
recording Potentiodynamic polarization curves and measuring the content of Ni ions, released into a SBF solution
using atomic absorption spectroscopy (AAS). Fourier transformation infrared radiation (FT-IR) and energy dispersive
spectroscopy were employed to verify the biocompatibility of the anodized and bare alloys after submersion in SBF. It
was shown that anodic oxidation in sulfuric acid significantly increases corrosion resistance and biocompatibility. This
layer improves corrosion resistance and Ni ion-release resistance by impeding the direct contact of the alloy with the
corrosion mediums i.e. Ringer and SBF solutions. The TiO2 oxide layer also decreases the releasing of Ni ions in to
SBF solution
Salma Bessalah, Jebahi Samira, Amel Raoufi, Asim Faraz, Mouldi Zagrouba, Mohamed Hammadi,
Volume 19, Issue 2 (6-2022)
Abstract
Abstract
Gelatin (GEL) is most extensively used in various fields, particularly in therapeutics and pharmaceuticals. GEL was extracted from goat skin using hot temperature extraction process and compared with that of commercial GEL. The physico-chemical characterization and functional properties were investigated by using temperature denaturation (Td), water-holding and fat-binding capacities (WHC and FBC), colour measurement and UV-light spectrum. In vitro biocompatibility was studied for the first time and was evaluated by blood coagulation index (BCI) and haemolytic tests for using as wounds dressing. The results revealed thermal stability of goat GEL at Td 37°C. WHC and FBC capacities represented 2.5 and 1.2 g/ml, respectively. The hunter colour spaces a*, b* and L* showed a -0.27, -1.97 and 25.23 values, respectively. UV-Vis absorption spectrum of the goat GEL showed a maximum absorption peak at 280 nm. The in vitro anticoagulant activities of extracting GEL were higher than 70% after incubation for one hour. After being in contact with red blood cells for 1 h, the haemolysis ratio increased from to 0.46 to 1.4 when the concentration of goat GEL increased from 1 to 50 mg/ml suggesting the safety of the tested samples. These results suggest that thromboresistivity and hemocompatibility of this biopolymer retained the biological activity of our samples for biomaterial applications. According to this, goat GEL successfully competes with, and significantly could be useful for substitution of bovine in wound healing.
