International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The current publication presents an approach for the elaboration of a disposable microfluidic hollow micro-channel using 2 photon polymerization technology and Photonic Professional GT2 (Nanoscribe, Germany) equipment. The design of a 3D model of a microchannel is realized by the CAD analysis software – SOLIDWORKS. A suitable laminar flow is generated by using computational fluid dynamics (CFD) software. As a result, the critical points of the pressure, velocity, and wall shear stress into the microfluidic channel are obtained. A real prototype of the hollow microfluidic device is created, using a highly innovative technology of 3D nanoprinting by twophoton polymerization. Experimental studies with dilute erythrocyte suspensions are conducted to test the functionality of the developed prototype of nano 3D printed microchannel.

The present study aims to model and analyze the images of induced in vitro blood clots from healthy donors and patients with type 2 diabetes mellitus (T2DM). By using the BioFlux microfluidic system, blood clots are induced at varying shear rates, and for different fibrinogen concentrations: native and highly modified. The fiber diameter of blood clots is analyzed by the scanning electron microscope (SEM). The obtained images of blood clots are imported as input data into the Image J software environment, after which obtained results for the area, number, and fibrin fiber diameter of blood clots, are further processed in a program developed in IntelliJ IDEA. It is found that patients with T2DM at the native concentration of fibrinogen at all studied shear rates form more blood clots having a larger total area, in comparison with the control group. At the higher modified fibrinogen concentration with increasing shear rate, the group with T2DM forms a smaller number of blood clots with a larger area, compared to healthy donors. From the SEM images, it is found, that denser fibrin networks are formed with increased fibrinogen concentration, which contains numerous thick fibrin fibеrs in healthy and diabetic individuals.

The main focus of this research is on the elaboration of the combined experimental approach and image analysis (based on the specialized software environments) to the research of erythrocyte aggregation, which is evaluated by the microfluidic device BioFlux. To realize a precise evaluation of the erythrocyte aggregation index based on the obtained, during the experiment images, are applied image processing toolbox from ImageJ and an elaborated computer program in IntelliJ IDEA (integrated development environment) as well. The obtained results for the index of erythrocyte aggregation, based on the developed methodology, show a statistically significant difference between the two studied groups with preeclampsia and healthy pregnant women.

In this pilot study, microfluidic flow analysis and atomic force microscopy (AFM), are used, to determine microrheological properties of the blood – aggregation, and deformability of erythrocytes in women with preeclampsia (PE). The aggregation of red blood cells (RBCs) is evaluated with the microfluidic system BioFlux, by applying an experimental approach and image analysis created by the authors of this study. The elastic properties of erythrocytes are defined by Young’s modulus, using AFM. The aggregation index of erythrocytes and their elastic modulus are statistically significantly increased in patients with PE, in comparison to healthy normotensive pregnant women. In addition, it is found that the RBCs are less deformable and the interaction between them in aggregates is stronger in women with preeclampsia as compared with healthy pregnant women.

The present study offers an important technological approach for the development of a disposable microfluidic channel using 3D nanoprinter – Photonic Professional GT2 (Nanoscribe, Germany). This publication aims to present 3D modelling, simulation, and prototype of a 3D nanoprinted microfluidic device for the investigation of blood cells. The design of 3D model of a microchannel is realized by the 3D CAD analysis software – SOLIDWORKS. A suitable laminar flow is generated by using computational fluid dynamics (CFD) software. As a result, the critical points of the pressure, velocity and wall shear stress into the microfluidic channel are obtained. An actual physical prototype of the proposed microfluidic device is developed, using a highly innovative technology of 3D nanoprinting by two-photon polymerization. Experimental studies with dilute erythrocyte suspensions are conducted to test the functionality of the developed real-world prototype of nano 3D printed microchannel.

The goal of the present study is to evaluate the elastic properties (Young’s modulus) of erythrocytes from healthy donors and patients with type 2 diabetes mellitus (T2DM), by using an atomic force microscope (AFM). Morphological and mechanical characteristics of red blood cells are studied in parallel by PeakForce QNM (Quantitative NanoMechanical Mapping) mode of AFM Dimensional ICON Bruker NanoScope V9 Instrument. Young’s modulus is calculated based on the mathematical model of Johnson-Kendall-Roberts by the application of the “two-point method”. AFM images of the erythrocytes from the healthy donors show that erythrocytes with a normal biconcave shape predominate. In patients with T2DM, the so-called erythrocyte polymorphism is studied. The Young’s modulus of erythrocytes, in patients with T2DM, significantly statistically increases by 27% (p≤0,001), compared to the data of healthy donors. The studied Young’s modulus by AFM can be used in clinical practice as a precise biomarker for the state of the red blood cells in T2DM.