New insight into erythrocyte through in vivo surface-enhanced Raman spectroscopy.

The article presents a noninvasive approach to the study of erythrocyte properties by means of a comparative analysis of signals obtained by surface-enhanced Raman spectroscopy (SERS) and resonance Raman spectroscopy (RS). We report step-by-step the procedure for preparing experimental samples containing erythrocytes in their normal physiological environment in a mixture of colloid solution with silver nanoparticles and the procedure for the optimization of SERS conditions to achieve high signal enhancement without affecting the properties of living erythrocytes. By means of three independent techniques, we demonstrate that under the proposed conditions a colloid solution of silver nanoparticles does not affect the properties of erythrocytes.

[Role of erythrocyte cytoplasmic structures in changes in the affinity of haemoglobin for oxygen].

Changes in the refractive index of the cytoplasm and the affinity of haemoporphyrin of erythrocyte haemoglobin to oxygen (pH, 2,3-diphosphoglycerate) have been investigated using laser interference microscopy and Raman spectroscopy. It has been established that a decrease in pH and an increase in the content of 2,3-diphosphoglycerate are accompanied by changes in both the form of the cell and the refractive index of the cytoplasm and the affinity of haemoporphyrin of hemoglobin to oxygen. It has been shown that as pH is reduced, the capacity of haemoporphyrin for binding oxygen decreases and as the concentration of 2,3-diphosphoglycerate is increased, the ability of haemoporphyrin for oxygen reabsorption increases.

[Investigation of the morphofunctional properties of human red blood cells under the conditions of 7-day dry immersion].

Morphobiochemistry of erythrocytes, erythropoiesis intensity (determined by iron metabolism and erythropoietin content), lipids and phospholipids of erythrocyte plasmatic membrane and oxygen binding and release by hemoglobin were studied in normal male volunteers for 7-d dry immersion. Investigations were performed before the experiment, on the last day in immersion (d-7) and on days 7 and 15 of recovery. After 7-d dry immersion, the volunteers exhibited a trend towards changes in red blood morphology, erythropoiesis intensity, and erythrocyte metabolism.

Evaluation of erythrocyte shape and status by laser interference microscopy.

The area, thickness, and volume of erythrocytes of different types (discocytes, stomatocytes, and echinocytes) from normal subjects and coronary patients were studied by laser interference microscopy. Increase of pH value leading to the stomatocyte-discocyte-echinocyte transformations resulted in a slight decrease of cell volume. In coronary patients, erythrocyte had larger area and volume and exhibited increased aggregation capacity compared to erythrocytes from controls.