Скачать полную версию статьи (в PDF формате)
З. Р. Ульберг, Т. Г. Грузина, А. С. Духин
«Коллоидно-биохимический механизм взаимодействия клетки с микро- и наночастицами»
PACS numbers: 81.16.Fg, 82.39.Wj, 82.70.Dd, 87.16.dp, 87.16.Uv, 87.16.Vy, 87.85.Qr
The colloid–biochemical mechanism of the interaction between live biological cells with microparticles and nanoparticles of metals is studied experimentally and substantiated theoretically. As shown, there are several independent lines of experimental evidence to suggest that cases of these interactions may strongly depend on the cell metabolism and ion pumps. Such dependence manifests itself at very large distances, on scale of microns, between particles and a cell. There is also an additional interaction mechanism that causes reversible aggregation of nanoparticles with some live cells. The functioning of ion pumps controls this mechanism. The relationships between the transmembrane potential and electrokinetic potential, which are experimentally observed by cell electrophoresis and should be taken into account when the Derjaguin–Landau–Verwey–Overbeek (DLVO) electrostatic component is important, unfortunately cannot explain these peculiar phenomena. On the other hand, there is experimental evidence that nanoparticles affect cell metabolism, and this effect depends on the particle size. This one might be related to another observation that gold nanoparticles penetrate inside the cells that allows them to interact with functions of cells’ organelles. Fourth different theoretical models have been suggested over the last four decades to explain these phenomena. We are very sceptical about microdielectrophoresis model due to nonlinear nature of underlying effect that leads to very high energy requirements. Another model, namely microdiffusiophoresis, seems to be more suitable in explaining the observed long-range interaction because the underlying effect is linear with the driving force, bringing substantial energy saving in comparison with the first model. The third model of ‘ion pump electroosmotic trap’ provides the desirable explanation of the role of ion pumps in reversible interactions with nanoparticles. Preliminary estimates indicate that reasonable values of the involved parameters could justify the sufficient energy necessary for the efficient functioning of such a trap. There is observation of similar electrohydrodynamical circulation with the same spatial symmetry near the ion exchange membrane when electric current passes through it.