Determination of some metal ions in aquatic environs by atomic absorption spectrometry after concentration with modified silica

137-142N-propylsalicylaldimine based on porous silica, as ion exchanger, is used for the separation and preconcentration of Fe3+, Co2+, Ni2+ and Zn2+ from surface water samples collected from eleven locations at Nile river, Mediterranean and Red seas and Mansoura city tap water. The effects of pH, time of stirring, concentration of eluting acids and some common ionic species on the separation and preconcentration of the investigated metal ions in synthetic aqueous solutions are studied. The results indicate that the optimum conditions for separation are pH = 9.0-9.5 and time of stirring = 30 min. HCl is better eluent for the investigated metal ions than HNO3 except for Fe3+.Citrate and EDTA show severe interference on the recovery of the metal ions, therefore, the water samples are previously oxidized to digest organic matter prior to the application process

Protective Effect of Starch-stabilized Selenium Nanoparticles against Melamine-induced Hepato-renal Toxicity in Male Albino Rats

Melamine and its analogues are illegally added to raise the apparent protein content in foods. The elevated concentrations of these compounds cause adverse effects in humans and animals. In this contribution, the protective effects of the synthesized starch-stabilized selenium nanoparticles (Se-NPs@starch) on melamine-induced hepato-renal toxicity have been systematically investigated. The Se-NPs@starch were characterized by X-ray photoelectron spectroscopy (XPS) analysis, energy dispersive spectroscopy (EDS) mapping analysis, TEM, and FT-IR. Starch plays a crucial role in the stabilization and dispersion of Se NPs, as noticed from the TEM and EDS investigations. Furthermore, the atomic ratio of Se distribution over the starch surface is approximately 1.67%. The current study was conducted on four groups of adult male rats, and the oral daily treatments for 28 days were as follows: group I served as control, group II received Se-NPs@starch, group III was exposed to melamine, while group IV was treated with melamine and Se-NPs@starch. The results reveal a significant alteration in the histoarchitecture of both hepatic and renal tissues induced by melamine. Furthermore, elevated liver and kidney function markers, high malondialdehyde, and increased expression levels of apoptosis-related genes besides a reduction in GSH and expression levels of antioxidant genes were observed in the melamine-exposed group. Interestingly, the administration of the Se-NPs@starch resulted in remarkable protection of rats against melamine-induced toxicity through increasing the antioxidant capacity and inhibiting oxidative damage. Collectively, this study provides affordable starch-stabilized Se-NPs with potent biological activity, making them auspicious candidates for prospective biomedical applications