Natural cyclic tetrapyrroles feature outstanding capacity for binding transition metal ions, furnishing Nature with the important metallo-porphyrinoid 'Pigments of Life', such as heme, chlorophyll (Chl) and vitamin B12. In contrast, linear tetrapyrroles are not generally ascribed a biologically relevant ability for metal-binding. Indeed, when heme or Chl are degraded to natural linear tetrapyrr...

Background: The rapid increase in agricultural and industrial development has made heavy metal pollution a serious environmental problem and public health threat; therefore, removal of heavy metals from water is important. The current study prepared DNPH@SDS@Fe3O4 nanoparticles as a novel and effective adsorbent for removal of Hg(II) ions from an aqueous solution. Methods: A selective adsorben...

sol-gel and polymeric membrane electrodes, based on thiacalix[4]arene as a neutral carrier, weresuccessfully developed for the detection of vo2+ in aqueous solutions. the sol-gel and pvcmembrane electrodes exhibited linear response with nernstian slopes of 29.3 and 28.4 mv perdecade, respectively, within the vanadyl ion concentration ranges from 1.0 × 10-6 to 1.0 × 10-1mol dm-3 and from 1.0 × 1...

Carbon nanotubes (CNTs) are a novel material that exhibits good adsorption behavior toward various toxic pollutants in aqueous solution. These adsorbents have a fast adsorption rate and high adsorption efficiency, efficient to remove various pollutants and they are easy to recover and reuse. These features highlight the suitability of CNTs for the treatment of water polluted with heavy metal io...

This study assesses the ability of mycelia of Rhizopus delemar (both free and immobilized on polyurethane foam) to remove heavy metals from single-ion solutions as well as from a mixture of them. All experiments were conducted using 0.5-5 mm solutions of CuSO4 x 5H2O, CoCl2-6H2O and FeSO4 7H2O. Mycelia immobilized on polyurethane foam cells showed some times increase in uptake compared with tha...

Mercury is highly toxic to human health in all of its oxidation states. Thus, developing a low cost, efficient metal ion sensor for the detection of mercury ions at concentration levels down to parts-per-billion (ppb) remains a challenge. In the present work, we have developed a silver nanoparticles (Ag-NPs) impregnated poly(vinyle alcohol) capped 4-nitrophenylanthranilate (PVA-NPA) complex for...

background: heavy metals, even at low concentrations, are harmful to human health and environment. cadmium as a heavy metal is highly toxic and can cause serious threat to living organisms. this research was designed to evaluate the adsorption potential of modified magnetic iron nanoparticles by 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol ligand for the removal of cadmium ions from water solu...

Poly(N-(hydroxymethyl)methacrylamide)-1-allyl-2-thiourea) hydrogels, poly(NHMMA-ATU), were synthesized by gamma radiation using (60)Co gamma source in the ternary mixture of NHMMA-ATU-H(2)O. These hydrogels were used for the specific gold, silver, platinum and palladium recovery, pre-concentration and matrix elimination from the solutions containing trace amounts of precious metal ions. Elimina...

background: the fatal effect of ionizing radiation on cells depends on linear energy transfer (let) level. the distribution of ionizing radiation is sparse and homogeneous for low let radiations such as x or γ, but it is dense and concentrated for high let radiation such as heavy-ions radiation. material and methods: chinese hamster ovary cells (cho-k1) were exposed to 4 gy fe-ion 2000 kev/m. ...

Adsorption and desorption studies on different types of adsorbents, including natural materials such as teak tree bark powder, rice husk, natural bentonite, different algae like Ecklonia maxima, Escherichia coli, Ascophyllum nodasum, Rhizopus nigricans, Cladophora fascicularis, goethite and soils of three nuclear power plant and artificial materials such as Fe oxide-coated sand, goethite pretre...