M. I. Oshtrakh

A high velocity resolution Mössbauer spectrometric system for biomedical research

An automated high-precision Mössbauer spectrometric system with a high velocity resolution for biomedical research is described. The results from testing the system are given. Applications of Mössbauer spectrometric system in the study of iron-containing proteins in normal and pathological cases demonstrate the possibilities for obtaining new data.

Mössbauer spectroscopy in biomedical research

This work discusses the main directions and results of the application of Mössbauer spectroscopy of iron containing species in biomedical research. These studies demonstrate the wide possibilities of Mössbauer spectroscopy to obtain physical parameters and information about the iron electronic structure in normal and pathological biomolecules, model compounds and pharmaceutical samples as well as about qualitative and quantitative changes of iron containing biomolecules during pathological processes or the effect of environmental factors. The results obtained may be useful for further understanding of the molecular nature of diseases and pathological processes.

Possibilities of Mössbauer spectroscopy with a high velocity resolution in studying small variations in 57Fe hyperfine parameters of iron-containing proteins

The possibilities of Mössbauer spectroscopy with a high velocity resolution in investigating small variations in the 57Fe hyperfine parameters of iron-containing proteins are demonstrated. Differences of quadrupole splitting for human and rabbit oxyhemoglobins were observed. Variations of quadrupole splitting and isomer shift for human liver ferritin and its model Imferon were revealed. Small differences in these parameters were also found for iron-storage proteins in normal chicken liver and spleen tissues and in such tissues from chickens with lymphoid leukemia.

Mössbauer and positron annihilation studies of microstructural peculiarities of iron-dextran complexes

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.

Biomedical Application of Mössbauer Spectroscopy with High Velocity Resolution: Preliminary Results

Application of Mossbauer spectroscopy with high velocity resolution in biomedical research demonstrated increase of this technique possibility to analyze small variations of the parameters, to study various samples from purified proteins to tissues with high quality measurements and fitting, and to analyze the quality of pharmaceutical compounds.

Mössbauer effect study of modified human hemoglobin

The relationship of the heme iron electronic structure and hemoglobin functions is of interest in order to understand the molecular nature of biological function. Previous Mossbauer study of various human hemoglobins demonstrated small variations of the Mossbauer hyperfine parameters (quadrupole splitting △EQ and isomer shift δ) for normal adult and fetal as well as for normal and leukemic oxyhemoglobins [1]. This fact indicates small variations of the heme iron electronic structure and stereochemistry in these hemoglobins. Moreover, it was shown that some features of the Mossbauer spectra related with the iron electronic structure nonequivalence in nonidentical subunits of tetrameric hemoglobins. Further study of human oxyhemoglobin modified by lyophilization demonstrated some changes of the heme iron electronic structure and stereochemistry [2]. On the other hand, some modified hemoglobins appeared useful as blood substitutes. Mossbauer study of hemoglobin modified by glutaraldehyde showed that cross-linking of hemoglobin by this reagent modified the heme iron stereochemistry [3]. In the present work we discuss the results of comparative study of human oxyhemoglobin modified by both pyridoxal-5 ′-phosphate which binds to the NH3-terminal groups of the β-chains and glutaraldehyde which mainly (70 %) cross-linked α- and β-subunits in each hemoglobin molecule.

Comparative study of the iron in pharmaceutically important iron-dextran complexes by Mössbauer effect

Iron-dextran complexes (IDC) are well known models of the iron storage protein ferritin which are used or elaborated for treatment of iron deficiency anemia. IDC consist of the iron core in the form of FeOOH surrounding with the dextran shell. In the present study we compare the iron state in various IDC including commercial and elaborated samples using Mossbauer spectroscopy. We analyzed IDC from different sources such as Imferon (Benger, USA), Imferon (Fisons, UK), Ferridextran (Leciva, CSSR), Dextrafer (USSR) and elaborated complexes named as IDC26, IDC81, IDC87, IDC3P, IDC4P, IDC6P, IDC8P. These complexes were studied in lyophilized form and solution. Mossbauer spectra of IDC were measured using the high precision spectrometer at 297 K and 87 K for lyophilized IDC and at 87 K for IDC in solution.

Study of Vitamins and Dietary Supplements Containing Ferrous Fumarate and Ferrous Sulfate Using Mössbauer Spectroscopy

A study of several samples of vitamins and dietary supplements containing ferrous fumarate and ferrous sulfate was carried out using Mossbauer spectroscopy with a high velocity resolution. A presence of ferrous and ferric impurities was revealed. Small variations of Mossbauer hyperfine parameters were found for both ferrous fumarates and ferrous sulfates in the investigated medicines.

Study of irradiated Hadfield steel using transmission Mössbauer spectroscopy with high velocity resolution and conversion electron Mössbauer spectroscopy

Proton irradiated Hadfield steel foil was studied using transmission Mossbauer spectroscopy with high velocity resolution and conversion electron Mossbauer spectroscopy. It was shown that proton irradiation leads to structural changes in the foil as well as to surface oxidation with ferric hydrous oxide formation (ferrihydrite). Moreover, oxidation on the foil underside was higher than on the foil right side.