Magneto-Medicine: Biological Aspects of Ferromagnetic Fine Particles

Abstract

The behavior of carbonyl iron ferromagnetic fine particles (FFP) introduced into the vascular system has been examined by biomicroscopical observations of a rat's mesenteric small vessels, extracorporeal bypass circulating system for a dog, histological observation for a rabbit, and magnetically controlled roentgenography for another dog, rat, and rabbit. In order to make FFP aggregate and also disperse in small vessels under the magnetic field, the following conditions were found to be necessary: (1) FFP are preferably coated with a suitable kind of substance. (2) The shape of the particles should be as spherical as possible. (3) Superposed magnetic field static as well as alternating should be applied. The solubility of FFP in the human blood with chelating agents was determined in vitro. The extracorporeal bypass circulating system was considered as a useful tool for the excretion of FFP. The Iron Rings Catheter was developed to take x-ray films of the internal surface of the right ventricle.