Quantification of magnetic nanoparticle concentration in pig lung tissue after magnetic aerosol drug targeting by magnetorelaxometry

Delivery of tiny aerosol droplets containing magnetic nanoparticles (MNP) to specific regions in the lungs guided by an external magnetic gradient field is a novel way of Magnetic Drug Targeting, which should allow to deposit high drug doses to a cancerous lung region together with reduced side-effects in unaffected tissue. Currently, this method is investigated in a pig lung model, a model being very similar to the human lung. The development of this procedure requires detailed knowledge about the biodistribution of MNP in different parts of the lung. Magnetorelaxometry (MRX) as a quantitative detection technique is used to determine the MNP distribution throughout the pig lungs after the aerosol targeting application. To this end, we extended our MRX measurement procedure to quantify the magnetic nanoparticle uptake in larger tissue samples with inhomogeneous particle distribution. Here, we present the results of the MRX quantification for an isolated pig lung. The absolute MNP uptake for individual lung lobes and the tissue concentration distribution over the whole lung is provided.