Magnetically assisted hemodialysis: ferromagnetic nanoparticles employed for toxins removal
Chronic Kidney Disease unavoidably leads to End Stage Renal Disease in which the kidneys have entirely lost their toxin-excretion ability. In this case some kind of renal replacement therapy is necessary. The most widely used therapy is conventional hemodialysis (HD), which is based on diffusion and convection physical phenomena. Specifically, during a HD session, the patient’s blood passes through an extracorporeal circulation line where the toxins are being removed into a dialysate through the semi-permeable membrane of a dialysis filter, called dialyser.
The subject of the present study is a development of HD, the so-called Magnetically Assisted Hemodialysis (MAHD). The purpose of MAHD is the more efficient, selective and faster removal of toxins compared to conventional HD. It is based on the preparation of Ferromagnetic Nanoparticle-Targeted Binding Substance (FN-TBS) conjugates, constructed of a biocompatible FN and a specially designed TBS that must have high affinity for the Toxic Target Substance (TTS) that we want to remove. The conjugates should be administered to the patient timely prior to the MAHD session, so that they will bind with the specific TTS as they circulate in the cardiovascular system. The complete conjugates FN-TBS-TTS are removed by a Magnetic Filter (MF) installed in series to the conventional HD filter. The function of the MF is based on the magnetic force acting on the FN-TBS-TTS conjugates, due to a magnetic field of high heterogeneity. The timely pre-administration of the FN-TBS conjugates and the fast kinetics of magnetic phenomena will enable the faster and overall more efficient removal of toxins from the blood. This makes MAHD more advantageous over HD.
In the present research study, we completed the chemical synthesis of FN-TBS conjugates and their subsequent structural, morphological and magnetic characterization. We used Human Serum Albumin (HSA) as TBS, due to its absolute biocompatibility and its high affinity for several TTSs. We also designed theoretically and constructed practically a prototype MF. The design of the MF included detailed theoretical simulation of the magnetic field produced by it, in order to choose the geometry that is most advantageous in respect to toxin-removal efficiency and safety terms. Finally, we tested the MF in standard laboratory conditions, where it successfully removed both unconjugated microparticles of iron (Fe) and conjugates of magnetite FNs with HSA (Fe3O4-HSA) dispersed in physiological saline.
Final Report (in Greek)
Efthymios Manios, Scientific Collaborator, NCSR Demokritos
Scientist in Charge: Dimosthenis Stamopoulos, Postdoctoral Researcher, NCSR Demorkritos
Vassiliki Gogola, Physicist
Nikolas Papachristos, PhD Candidate, NCSR Demokritos
Georgios Papageorgiou, PhD Candidate, NCSR Demokritos
Irini Grapsa, Assistant Professor, Medical School, National and Kapodistrian University of Athens