ИСТИНА

Nanomedicine has reached such a level of development that it is beginning to be considered as a separate field of life sciences. The use of magnetic nanoparticles (MNPs) and magnetic nanostruc- tures in medicine is a complex interdisciplinary scientific and practical task that is far from being complete [1]. The goals of the search for new medicines using MNPs are diverse: improvement of the therapeutic index by increasing efficiency and/or reducing toxicity; targeted drug delivery, specific to the type of tissue or even at the cellular or sub-cellular level; improving the pharma- ceutical properties of therapeutic molecules – stability, solubility, circulation time in the body, increasing the concentration of the drug in the diseased organ; the possibility of controlled release of the drug; the possibility of targeted intracellular delivery of therapeutic agents based on biologi- cal macromolecules – DNA and RNA; joint delivery of complex therapeutic agents to increase the effectiveness and overcome drug resistance; the possibility of more accurate selection of the ratio of components of a complex drug taking into account a specific patient (the so-called “personalized medicine”; the possibility of successful drug transcytosis, i.e. overcoming endothelial, for example, blood-brain and epithelial barriers; the possibility of more accurate diagnostic methods (visualiza- tion); prospects of simultaneous diagnosis and therapy, including in real time (theranostics); the possibility of using their own specific physical and chemical properties of nanocarriers for therapy. The main feature that distinguishes MNPs from other types of nanocarriers of medicines is the ability to influence them with an external physical factors, for example, electromagnetic field, and use them in various biophysical methods and approaches. For example, magnetic field can provide control over the movement of MNPs and their accumulation in the target local areas of the body and, if necessary, significant heating (in the hyperthermia method). For medical applications, MNPs based on iron oxides – magnetite and maghemite are most suitable, since nanophase iron oxides are low-toxic, widespread in living systems and can be metabolized by cells. When using MNPs in therapeutic or diagnostic methods, it is extremely important to directly control the spatial location of nanoparticles inside the patient’s body. This is especially important in methods with controlled release of the drug in the target area of the body, which should be performed only after the MNPs of the target organ has been reached. A very promising experimental method that solves this problem is called MPI (magnetic particle imaging). The disadvantages of modern medical methods using MNPs are due to their complexity, insuf- ficient reliability and low efficiency. Only in very few cases it was possible to put into practice the methods of magnetic hyperthermia and controlled targeted drug delivery. The practical application of MNPs for diagnostic purposes is more successful, despite many problems associated with side effects. The reasons preventing the practical use of MNPs are divided into three groups: (i) scientific (fundamental or technical); (ii) clinical (medical and social); (iii) marketing. Overcoming all these challenges requires new integrated multidisciplinary approaches.