This work describes the possibility of fabrication of the large batches of magnetic nanoparticles using electrophysical methods of electric explosion of the wire, laser target evaporation and spark discharge. Bioapplications of nanoparticles require the production of magnetic materials in the form of stabilized aqueous suspensions or hydrogels with magnetic fillers; therefore, some details of the synthesis of these materials and their certification are discussed. The peculiarities of interaction of magnetic nanoparticles with biological systems, the problem of biocompatibility, the possibility of using ferrogel substrates for the needs of cell technologies and regenerative medicine, as well as implication of biomimetics in the development of magnetic biosensors are considered. The results of the analysis of a number of different biological experiments carried out with suspensions of various types, obtained based on the same batch of MNPs are presented. An analysis of examples of magnetic biodetection and existing theoretical approaches will make it possible to assess the prospects of this scientific direction for the creation of highly sensitive thin film sensors based on the giant magnetoimpedance effect for biomedical applications.