Pierre Danhier1, Geraldine Depraeter1, Sebastien Boutry2, Isabelle Mahieu2, Robert N. Muller2, Pierre Sonveaux3, Caroline Bouzin3, Olivier Feron3, Philippe Leveque1, Julie Magat1, Benedicte Jordan1, Bernard Gallez1
1Louvain Drug Research Institute, Biomedical Magnetic Resonance Research Group, University of Louvain, Brussels, Belgium; 2University of Mons, Mons, Belgium; 3Institute of Experimental & Clinical Research, University of Louvain, Brussels, Belgium
We propose here to implement Electron Paramagnetic Resonance (EPR) as a very sensitive method to quantify iron oxide concentration (in cells and tissues). Iron oxide particles exhibit an EPR spectrum, which directly reflects the number of iron oxide particles in a sample. In order to compare EPR with existing methods (Perls Prussian blue reaction, and fluorimetry), we labeled tumor cells (Melanoma B16F10-luc, fibrosarcoma KHT-luc) and fibroblasts (3T3) with fluorescent iron oxide particles, and defined the limit of detection of the different techniques. EPR is a fast, easy, and highly sensitive method (compared to other methods) to quantify iron oxide content after magnetic labelling.