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Various compositions of polyvinyl alcohol/acrylic acid Poly(PVA/AAc) hydrogels are prepared using of gamma radiation. The properties of the prepared poly(PVA/AAc) hydrogel and poly(PVA/AAc/magnesium oxide (MgO)) composite hydrogel were characterized by various techniques such as fourier transform infrared (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy. The TEM and XRD patterns of MgO nanoparticles indicate that the MgO with average particle size ranged from 18.11 nm to 45.6 nm. The gel (%) of the prepared poly(PVA/AAc) hydrogel with different contents of AAc increased with increasing both irradiation dose and AAc content. The swelling (%) of poly(PVA/AAc) hydrogel at different irradiation doses and different AAc contents found to be decreased with increasing both irradiation dose and AAc contents. The effect of incorporation of MgO nanoparticles into the poly(PVA/AAc) hydrogel matrix for absorption of boron from aqueous solution under various factors such as different concentrations of boron, different concentrations of MgO, and at different treatment times was investigated. From the study, the modified poly(PVA: AAc/MgO) composite hydrogel with composition (80:20 vol.%/5 wt%) has higher substitution, macroporous structure and characterized by better performance in swelling and boron uptake capacity than poly(PVA/AAc) hydrogel with composition (80/20 vol.%). The high absorption of boron indicates complex formation via ion exchange and chelation between poly(PVA/AAc/MgO) and boron due to the presence of different moieties provided by acrylic–acrylic, acrylic-PVA, and PVA-PVA. [ABSTRACT FROM AUTHOR]

Modification of low density polyethylene (LDPE) films by blending with Polylactic acid (PLA) and Starch (St) were carried out. Also, the study describes the comparison of two curing methods one by thermal curing at 70°C and the other is radiation curing at dose 20 kGy for the bioblend film composed of LDPE/PLA/St with composition (98%:1%:1% wt%). The efficiency of modification was determined by using different devices such as Fourier transform infrared (FTIR), mechanical, TGA, and XRD. In addition, the properties of the different bioblends were compared with other synthetic polymers such as commercial LDPE and blank LDPE. The results show that the improved properties of radiation cured method at dose 20 kGy than thermal treatment method at 70°C. The radiation cured bioblend film show good thermal stability either shown by the TGA results or against heating aging from ambient temperature up to 60°C than thermally treated blend film at 70°C. The radiation cured bioblend film found to be stable against UV‐ exposure with increasing time of exposure up to 30 min at higher wavelength (λ = 320 nm), which simulate ultraviolet radiation from sunshine. The modified properties of prepared radiation cured bioblend film are due to increase in interfacial adhesion bond between LDPE, PLA, and Starch by effect of irradiation dose at 20 kGy. The modified radiation cured bioblend films at 20 kGy can be applied in different fields such as packaging due to improvement in chemical, thermal, and mechanical properties that could partially replace the traditional petrochemical plastics. [ABSTRACT FROM AUTHOR]

The purpose of the current study is to prepare chitosan nanoparticles by gamma radiation as a new brain delivery system for memantine to improve its therapeutic efficiency. Fourier-transform infrared analysis of chitosan nanoparticles showed the characteristic peaks of chitosan and the reduction of particle size induced by irradiation at doses 10, 20 and 30 kGy. The solubility of chitosan nanoparticles was tested using different solvents and exhibited good solubility in both water and 1% acetic acid than other tested solvents at 80°C. Different formulations containing memantine - loaded chitosan nanoparticles were evaluated for brain targeting on aluminum-induced Alzheimer's disease in rats. Memory deficit was evaluated using the Morris water maze test. The levels of amyloid-β peptide, tumour necrosis factor alpha, interleukin-1β and interleukin-6 in brain tissues as well as the serum level of brain-derived neurotrophic factor were assayed. Data demonstrated that memantine - loaded chitosan nanoparticles 1:1 transported memantine effectively into the brain compared to free memantine as evidenced by better behaviour performance and biochemical amelioration and confirmed by histopathological examination in Alzheimer's disease rats. Interestingly, the therapeutic effect of memantine - loaded chitosan nanoparticles 1:1 was superior to memantine - loaded chitosan nanoparticles 1:2 and memantine - loaded chitosan nanoparticles 2:1. Based on these findings, it is reasonable to suggest that memantine - loaded chitosan nanoparticles 1:1 could be a promising approach for Alzheimer's disease. [ABSTRACT FROM AUTHOR]