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  • Author or Editor: V. Semionkin x
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Abstract  

Structural modifications of human adult oxyhemoglobin in concentrated solution were studied by Mössbauer and positron life-time spectroscopies. The effects of non-sterile degradation and irradiation by -rays were compared by both techniques. It was found that positron annihilation parameters were sensitive to the structural modifications of hemoglobin molecules in solution and could be related with the conformational states of hemoglobin.

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Abstract  

An improvement in velocity resolution of Mössbauer spectroscopy permitted us to carry out a more detailed study of iron chemical state in various iron-containing compounds in a wide range of research. New possibilities of Mössbauer spectroscopy with high velocity resolution were shown in the studies of meteorites, nanocomposites, pharmaceuticals and biological subjects.

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Abstract  

The microstructural peculiarities of pharmaceutically important iron-dextran complexes were studied by Mössbauer and positron annihilation techniques. The results of Mössbauer spectroscopy showed variations of the iron cores in iron-dextran complexes containing different forms of FeOOH and different electronic and magnetic states of iron. The results of angular correlations of annihilation radiation and positron life-time spectroscopies showed microstructural variations of the dextran shell of the iron-dextran complexes.

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Summary  

An analysis of the iron state in commercial pharmaceuticals containing ferric and ferrous iron compounds, which are used for treatment of iron deficiency, was made by Mössbauer spectroscopy. Small variations of the FeOOH cores of injectable iron-dextran complexes were observed. The presence of ferrous impurity in iron-dextran complexes was found. Characterization of the iron state in vitamins and dietary supplements containing ferrous compounds was made. The presence of ferrous and ferric impurities and iron compounds that were in disagreement with compounds announced by the manufacturer was detected by Mössbauer spectroscopy.

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Abstract  

Mössbauer spectroscopy is a useful technique for biomedical applications. To increase analytical possibilities and quality of its biomedical applications a new Mössbauer spectrometric system was developed. This system based on a highly stable, sensitive and precision spectrometer SM-2201 with high velocity resolution and a temperature variable liquid nitrogen cryostat with a moving absorber. The first results of Mössbauer spectroscopy with high velocity resolution demonstrated a decrease in the experimental error in the determination of 57Fe hyperfine parameters and, therefore, an increase of accuracy in analysis of small variations of the iron electronic structure, as well as more reliable fitting of complicated spectra.

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Summary  

Characterization of iron storage proteins in liver and spleen from normal chicken and chicken with lymphoid leukemia in comparison with human liver ferritin were considered by Mössbauer spectroscopy (preliminary results). Small differences in Mössbauer hyperfine parameters for both normal and lymphoid leukemia chicken liver and spleen were observed. The value of quadrupole splitting for human liver ferritin was higher than those for chicken tissues. A decrease of iron content in lymphoid leukemia chicken tissues was also found, however, the reason of this fact (pathology or feeding) was not clear yet.

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