An Approach to Identifying Phenomena Accompanying Micro and Nanoparticles in Contact With Irregular Vessel Walls

The objective of this paper is to present the method for determining the nature and values of the forces needed to set micro and nanoparticles sitting immobile at the blood vessel wall in motion. The problem was tackled in two ways. Microparticles were examined as objects coming into contact with the wall with the actual large arterioletype vessel structure. The forces acting on microparticles 10, 30, and 50 μm in diameter were determined: drag force F
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, lift force F
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, electrostatic force F
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, and gravity force F
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. Fluid-structure interaction analysis was used to research the problem. However, nanoparticles were examined as objects coming into contact with the endothelial surface layer (ESL). Resistance forces during the movement of nanoparticles 20, 50, and 100 nm in diameter in the ESL were determined. The same was done for aggregates of nanoparticles 50 nm in diameter. Local irregularities in wall surface are important for microparticles.Small irregularities with the small values of electrostatic force F
_E
can effectively stop the particle. In the case of nanoparticles, the key is the interaction of the particle with ESL. The research methodology presented can be used to better understand the particle- blood vessel wall interaction phenomena, leading to a more informed particle movement control. The new application of known calculation methods presented in this paper can be successfully used as an additional tool that simplifies planning and design of strategies for drug delivery by means of micro and nanoparticles.