O. B. Mokhodoeva

Sorption Preconcentration in Combined Methods for the Determination of Noble Metals

Combined methods for the determination of noble metals with the use of sorption preconcentration with complexing, anion-exchange, and other sorbents are reviewed. Characteristics of sorbents, techniques of sorption preconcentration, and techniques for the preparation of a concentrate for determination are considered. Features of instrumental methods for the determination of noble metals in the analysis of different materials are discussed. Examples of the use of sorption preconcentration in combined methods for the determination of noble metals are given from publications between 1996–2005.

Solid-phase extractants for radionuclide preconcentration and separation. New possibilities

A review of solid-phase extractants for radionuclide preconcentration and separation is presented. Examples of solid-phase extractants prepared by impregnation of various supports with compounds used in liquid extraction are considered. The possibilities of using carbon nanotubes and ionic liquids for preparing new solid-phase extractants are discussed. Experimental data on sorption recovery of actinides, europium, and palladium from nitric acid solutions with solid-phase extractants prepared by impregnation of carbon nanotubes and polymeric supports with ionic liquids and ligands are presented.

Preconcentration of noble metals with the POLYORGS 4 complexing sorbent under the action of microwave irradiation

The sorption of Au(III), Pd(II), Pt(IV), Rh(III), and Ir(IV) with the POLYORGS 4 complexing sorbent in the static mode was studied at room temperature and on thermal and microwave heating. It was demonstrated that the sorption of noble metals from 1 M HCl and 1 M HNO3 solutions can be substantially accelerated under the action of microwave irradiation. Based on the obtained data, the conditions of the group preconcentration of noble metals for their subsequent determination by the ETAAS and ICP AES methods were selected. The preconcentration procedure was used for the analysis of certified reference material SARM-7B (platinum-containing ore), VT-1 (copper-nickel sulfide ore), and the alloy of copper with noble metals.

New solid extractants for preconcentrating noble metals

New solid extractants are synthesized with the use of imidazolium and phosphonium ionic liquids for preconcentrating noble metals. Ionic liquids are selected and conditions for their immobilization on various solid matrices are found. The adsorption properties of the synthesized solid extractants for platinum(IV) in hydrochloric acid solutions are studied. The solid extractants obtained by binding 1-hexadecyl-3-methylimidazolium bromide and trihexyltetradecylphosphonium chloride to polymeric matrices and multiwall carbon nanotubes possess good kinetic properties and selectivity in 1 M HCl, and can be used to preconcentrate Pt(IV), Pd(II), and Au(III) in combined methods of their determination.

A new combined ETAAS method for the determination of platinum, palladium, and gold traces in natural samples

A new combined method is developed for determining trace platinum, palladium, and gold in natural materials of complex composition. The method involves sorption preconcentration with solid-phase extractants obtained by impregnating polymer supports (hypercrosslinked and highly crosslinked polystyrene resins) with an imidazolium ionic liquid (1-hexadecyl-3-methylimidazolium bromide), elution with acetone under normal conditions or with a solution of thiourea in 1 M HCl under microwave heating, and the ETAAS determination of analytes in the eluate. The efficiency of the method is confirmed by the analysis of various ores and rocks.

Solid-phase extractants based on taunit carbon nanotubes for actinide and REE preconcentration from nitric acid solutions

The sorption properties of solid-phase extractants (SPEs) prepared by impregnation of Taunit carbon nanotubes with adducts of diphenyl(dibutylcarbamoylmethyl)phosphine oxide (CMPO) and tri-n-octylphosphine oxide (TOPO) in HNO3 solutions were studied. The SPEs exhibit high ability to sorb U(VI), Pu(IV), Np(V), Am(III), and Eu(III) from nitric acid solutions, with good kinetic properties. The impregnation conditions and distribution coefficients of the radionuclides in their recovery from 3 M HNO3 were determined. The possibility of preparing SPEs by Taunit impregnation in HNO3 solutions with adducts of tributyl phosphate (TBP) and N,N′-dimethyl-N,N′-dioctylhexylethoxymalonamide (DMDOHEMA) and with Cyphos IL-101 phosphonium ionic liquid was demonstrated.

Progress in Targeted Alpha-Particle Therapy. What We Learned about Recoils Release from In Vivo Generators

This review summarizes recent progress and developments as well as the most important pitfalls in targeted alpha-particle therapy, covering single alpha-particle emitters as well as in vivo alpha-particle generators. It discusses the production of radionuclides like 211At, 223Ra, 225Ac/213Bi, labelling and delivery employing various targeting vectors (small molecules, chelators for alpha-emitting nuclides and their biomolecular targets as well as nanocarriers), general radiopharmaceutical issues, preclinical studies, and clinical trials including the possibilities of therapy prognosis and follow-up imaging. Special attention is given to the nuclear recoil effect and its impacts on the possible use of alpha emitters for cancer treatment, proper dose estimation, and labelling chemistry. The most recent and important achievements in the development of alpha emitters carrying vectors for preclinical and clinical use are highlighted along with an outlook for future developments.