Svetlana B. Norina

Behaviour of erythrocytes in high gradient magnetic field

Abstract To obtain magnetic characteristics of single biological cells in vivo behaviour of human erythrocytes has been investigated in single wire high gradient magnetic separator (HGMS) experiments. Phenomenon of diamagnetic capture in the field reduction region near transversely magnetized wire has been discovered for erythrocytes with oxyhemoglobin. The trajectories of erythrocytes were observed in single wire HGMS experiments in paramagnetic and diagmagnetic modes of motion. The values of susceptibility of individual erythrocytes in various states were estimated.

Image analysis of bioparticles accumulation and diamagnetic alignment in high-gradient magnetic field

Magnetic properties of biological particles are measured in high-gradient magnetic separation (HGMS) analysis, revealing the concentrating process of nucleoprotein particles, ferritin, red blood cells, and eggs. A magnetic force acting on micrometer and submicrometer biological particles having diamagnetic or paramagnetic susceptibility with respect to the solution causes their movement and accumulation in gradient magnetic fields dependent on the values of the magnetic moments. The methods developed enable us to obtain the magnetic moments values of single particles and their assembly directly from magnetic separation and image analyses without assuming the detection of sizes. Our precision methods for the measurement of the capture traveling (magnetic diffusion) time and the accumulation (magnetic sedimentation) radius in HGMS show that it is really possible to determine the weak dia- or paramagnetic shifts of magnetic susceptibility up to 0.7x10(-10) (SI units). HGMS analysis of the concentrating process of nucleoprotein granules (microcells, DNA granules, or nucleosome core particles) with polarization microscopy reveals phase transitions for DNA in granules, and separation accumulation of particles enables the determination of the diamagnetic susceptibility and anisotropy properties. Magnetic concentration effects always occur in living systems because micrometer-located gradient magnetic fields inside an organism are strong enough to cause drifts of cellular complexes and organelles of micrometer and submicrometer sizes. We report the appearance of superparamagnetic contamination inside developing shrimp eggs. In the developing shrimps eggs, ferritin aggregates are observed under weak gradient magnetic fields and diaparaferromagnetic changes are detected. A significant interruption of egg development is revealed in such fields.

Optical study of magnetic sedimentation and orientable properties of blood cells

Magnetic sedimentation processes near ferromagnetic wire were applied for the cellular and the biotechnological monitoring. Numerous biological applications of magnetic sedimentation, or high gradient magnetic separation (HGMS), achieved mainly for human blood cells, have shown that it is possible to distinguish between the diamagnetic Fe-zero-spin oxidized states and the paramagnetic Fe-high-spin reduced ones in red blood cells. The precision methods of the measurements of capture travelling (magnetic diffusion) time or accumulation (magnetic sedimentation) radius in HGMS have shown that it is really to determine the weak dia- or paramagnetic shifts of magnetic susceptibility up to 0.7 (DOT) 10-10 (SI). The capture and sedimentation of particles with 5 - 40 micrometers sizes on single magnetized wires were investigated using microscopic video-recording type. Magnetic susceptibility bars for cells in normal and disturbed states demonstrated the high reproducibility and narrow distribution patterns.

Spectroscopy of Intensity Fluctuations of Cell Dynamics, Tissue Reflectance and Auto-Fluorescence

Dynamic characteristics and auto-fluorescence of bio-micro-objects were indicated with a portable device and a software supplementation to a microscope. The cell motility was investigated with using the set up attached to a microscopic ocular tube for the frequency photo-detection of cell motion supplied with 6 graphs software to register Fourier spectra, the intensity, and amplitude real-time parameters of the motility under temperature, light and magnetic influences. Human skin and vessels showed auto-fluorescence detected with the device during time and influences.

Coherent vibrations of cells under magnetic influences

The speckle pulse-analyzer is used to measure the human resonant mechanovibrations under pulsating magnetic influences, to conduct their Fourier-spectra analysis and dynamical processes documentation. The fast coherent response of organisms on super weak ultra-low-frequency magnetic field was recorded on coherent cells vibrations. Possible biophysical mechanisms are suggested and proved on experiments with blood cells. In particular, gradient steady magnetic fields could reveal the vibrational potency of cells in pulsating magnetic fields provided of the appearance of cellular magnetic sign-difference and anisotropy under pathological situations in organism. From the disturbances oxidative process in cells which give the paramagnetic shift of cells magnetic susceptibility relatively the normal state, the single cells or certain parts of organs become more paramagnetic than other native tissue. Arising magnetic vectors of living system appear oscillations in pulsating magnetic fields.

Apoptotic Cardiomyocyte Beating Frequency Detected with Optical Intensity Fluctuation Spectrometer

Dynamical spectroscopy of intensity fluctuations allows measurements of the dynamic scattering of light and motility detection of biomicroparticles in suspensions and tissues. Spectroscopy of intensity fluctuations allows the detection of complex rhythms of the rat heart in vitro. The optical portable spectrometer used detected Fourier spectra and real-time rhythms in rat cardiomyocytes, the beating in the infarct model of the rat heart. The findings indicated that single cardiomyocyte beating was superimposed on the autowave heart tissue rhythm and associated with the apoptotic process. A dependence was observed of the superposition of individual cardiomyocyte beatings at 8–22 Hz on their metabolic state and autooscillations of isolated rat heart tissue at 1–2 Hz.

Diamagnetic accumulation and alignment of nucleoprotein microparticles in high gradient magnetic field

Magnetic force acting on single micron and submicron biological particles having diamagnetic susceptibility in the respect to solution caused their movement and accumulation in gradient magnetic fields. Methods developed allowed the obtaining of magnetic moment values of single particles and their assembly directly from magnetic separation image analysis not assuming to detect sizes. Our precision methods of the measurements of capture traveling time and accumulation radius, in high gradient magnetic separation (HGMS) analysis have shown the determined shifts of magnetic susceptibility up to 0.5/spl middot/10/sup -9/ (CGS). Image analysis of the concentrating process of nucleoprotein granules (micro-cells, or DNA-granules) with polarization microscopy revealed phase transitions for DNA, and separation accumulation of particles allowed the determination of the diamagnetic moments and anisotropy properties.

Magnetophoretic and optical study of anisotropic magnetic properties of biomicroparticles containing reactive oxygen species or ferritin

Magnetophoretic and optical methods combined with pulsating weak magnetic field 1-10 Hz were applied to observe resonant vibrations of biological microparticles with anisotropic magnetic properties. Modeling of oxidative disorders in tissues was realized using reactive oxygen species (ROS) initiation and ferritin incorporation into porous sorbent beads and blood cells. Microscopic video recording of cells in high gradient magnetic separation allowed to determinate changes of magnetic moments under stress activating influences.

Motility and ciliary beating frequency detection of cells and invertebrates for environmental biomonitoring

Light microscopic dynamical images and amplitude-frequency spectra by computerized documentation were used for the experimental evidence that the biological rhythms and ciliary beating cycles can be used as relevant tool for the biomonitoring of environmental pollutants and influences. At present work some lower animals, invertebrates: Protozoa cells, Rotifera, Mollusca gill cilia epithelium, Polychaeta served the convenient model biosystem for investigations due there ciliary and contractile organs. The narrow Fourier- spectra bands were revealed for large number of organisms, which were shifted or diffused by heavy metal salts, ATP, Ca-, Mg-ions and organic mixture in concentrations 10-2-10-6 M. The three phase of the ciliary beating were obtained for single cilium. The group of cilia with a good metachronal coordination gave the narrow characteristic Fourier bands, while the perturbances from the external influences led to the spreading and shifting of the main bands. These effects could serve as test-methods for the environmental biomonitoring of pollutants.