Acute toxicity and irritation of water‐based dextran‐coated magnetic fluid injected in mice

Abstract Based on the elements that magnetic nanoparticles could heat in an alternating magnetic field, magnetic fluid hyperthermia occurred to inhibit tumor growth in vivo . However, biocompatibility of those fluids as well as the fluid–body interaction remains unclear. In this article, acute toxicity and irritation of the water‐based dextran‐coated magnetic fluid (dextran‐magnetic fluid) injected into mice subcutaneous tissues were examined. Lethal dosage 50 of single treatment with the magnetic fluid was 4409.61 ± 514.93 mg/kg. When injected with 30 mg/0.3 mL dextran‐magnetic fluid, activities of glutamicoxalacetictransaminase (AST) and glutamicpyruvictransaminase (ALT) and cell number of mice blood did not change statistically. Hemangiectasia and leucocytes infiltration were seen in subcutaneous tissues and these phenomena almost disappeared 72 h later. That is to say, the dextran‐magnetic fluid was tolerable, safe, and biocompatible. The work is a basic for application of the dextran‐magnetic fluid in subcutaneous tumor therapy. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008