Altangerel Amarjargal

Electrospun polyurethane/Eudragit ® L100-55 composite mats for the pH dependent release of paclitaxel on duodenal stent cover application.

A nanofiber composite mat of PU and Eudragit(®) L100-55 was created using electrospinning process. The pH dependent release of paclitaxel was successfully done with the use of PU/EL100-55 nanocomposite mats as the controlling platform. The morphology of the nanofiber composites was surveyed using FESEM and ratios of the polymers affects the diameter of the nanofiber. Characterization of the nanofiber composite mat was done using FTIR, DSC-TGA method. The release rate of paclitaxel was determined and analyzed by in vitro drug release method. In order to mimic the condition of a human duodenum, the fibers were submersed on PBS of different pH levels (4.0, 6.0,) respectively, and then analyzed using high performance liquid chromatography (HPLC). Composite mats submersed in PBS with pH 4.0 showed lesser release profile compared to mats submersed in PBS with pH of 6.0. The composite mat has adequate mechanical properties and in vitro cell biocompatibility indicating that the material can be used for drug eluting stent cover application.

Simple fabrication of Ag nanoparticle-impregnated electrospun nanofibres as SERS substrates

A facile method for the fabrication of electrospun polyurethane (PU) nanofibres impregnated with Ag nanoparticles (NPs) as an efficient and free-standing surface-enhanced Raman scattering (SERS) substrates is reported here. Electrospinning was used to produce polymeric nanofibrous matrix, while a liquid polyol(ethylene glycol) solvent under low temperature was used not only to reduce Ag+to Ag0, but also was employed as the in situ growth medium for well-dispersed Ag NPs on the surface of fibre nets. Large enhancement in Raman signals of 4-mercaptobenzoic acid analytes could be realized in the present Ag/PU nanofibres due to the presence of SERS ‘hotspots’ by means of appropriate interparticle gap.

Characterization and Photocatalytic Efficiency of TiO2/Ti Beads Fabricated by Simple Heat-Treatment

The goal of the present study was to investigate the photocatalytic efficiency of titanium dioxide (TiO 2 ) formed on titanium (Ti) bead substrate (referred herein as TiO 2 /Ti beads) by heat treatment when exposing to ultraviolet (UV) light irradiation. Escherichia coli was used as the model test organism. The results show 4-log and 7-log decrease in bacterial concentration after a test time of 15 and 120 min, respectively, using TiO 2 /Ti beads irradiated with UV light in a tin-foil covered beaker. This article presents the potential of TiO 2 on Ti bead substrate formed by simple heat-treatment together with UV light for bacterial inactivation.

Efficacy of zinc and tourmaline in mitigating corrosion of carbon steel in non-flow mode

Laboratory corrosion immersion tests were carried out to investigate the effectiveness of a physical water treatment (PWT) using zinc and ceramic tourmaline-based catalytic materials for the control of carbon steel corrosion in acidic still water (i.e., pH 4.5–5). The tests were carried out at different water temperatures over 168 h. Our results showed a maximum of 22 % reduction in the corrosion rate using PWT in comparison with the control case. Furthermore, the corrosion products depicted more agglomerated particles after the PWT treatment. In both cases, differences were observed in the crystal structures, showing in general lower corrosion activity when PWT was used. The present results could find potential applications in water distribution systems and where metallic materials are exposed to stagnant acidic water.