Scientists Developed an Original Computer Model for the Study of Magnetic Nanogels

09:22, December 23, 2021

The smart gel's behavior in the body can be studied without experiments on animals

The team of researchers, which includes employees of the UrFU, figured out how the nanogel moves in the hydrodynamic flow of blood vessels. In other words, how a smart carrier for a drug moves through the body. To do this, mathematicians developed a computational model of two types of nanogels (with cobalt and cobalt ferrite) that replicates the features of real samples. The model allows the drug to be analyzed by supercomputers without animal studies. The study is published in the Journal of Molecular Liquids.

Magnetic gels - soft polymers with embedded magnetic nanoparticles - are promising magnetically controlled drug carriers. Micro- and nanogels are used for drug delivery and gradual release of drugs, particularly toxic anticancer drugs. Magnetic particles are tightly bound to the gel polymer matrix, then the drug is placed into the magnetic nanogel. The suspension is injected into the human bloodstream, and the drug is localized near the inflammation.

"The size of the nanogels under study is less than one micron, which is about 100 times smaller than the size of red blood cells. Our study was motivated by the question: how does the magnetic nanogel behave in the hydrodynamic flow of blood? What, for example, if the current ruptured the gel or swirled it so hard that all of the medicine would be ejected somewhere along the way to the inflammation focus. Using computer simulations, we found that the nanogel, even in arteries with turbulent flow, will travel slowly and quietly. This means that the drug is stable and will be able to deliver the drug to a given point," explains study co-author Ivan Novikov, a PhD student at the Faculty of Physics at the University of Vienna.

Scientists note that the experimental characterization of the process of drug delivery is a complex task. Carrying out experiments on animals makes it possible to see only the end result - the effectiveness or ineffectiveness of the treatment, but the size of nanogels and the flow rate do not allow to determine the impact of the flow on the shape and internal structure of the gel. To study the processes taking place inside the body, scientists for the first time applied computer modeling using the molecular dynamics method.

"We developed an original computational model of magnetic nanogels that quite accurately recreates the characteristics and properties of real samples. We also created realistic blood flow conditions. This allows us to simulate the process of injecting the drug into the blood and study the mechanical response of the gel to it. Using this method, we can study different types of nanogels, compare their behavior, understand the influence of nanoparticles' magnetization on their movement in the body, and thus develop recommendations for using different magnetic gels in biomedical applications, microrheology or tissue engineering," notes Ekaterina Novak, Associate Professor at the Department of Theoretical and Mathematical Physics, senior researcher at the Laboratory of Mathematical Modeling of Physical and Chemical Processes in Multiphase Media at UrFU.

At this stage, the scientists have focused exclusively on the behavior of the nanogel in the absence of external magnetic influence. In the future, they plan to learn how to control gels of different compositions floating in the flow when exposed to an external magnetic field: alternating, rotating, or pulsating.

In addition, scientists from Ural Federal University and the University of Vienna (Austria) worked on the study. This study was supported by a grant from the Russian Science Foundation (Project No. 19-12-00209).

Reference

Molecular dynamics is a method of computer simulation aimed at analyzing the properties of systems composed of a large number of moving atoms, molecules, colloids, polymers, and other objects of rather small size. Research using this method is similar to natural experiments, but provides more information on the processes occurring inside the body. In modeling it is possible to accurately take into account the interactions of the studied objects during a certain time interval, which allows to study the dynamic evolution of the system.