Development of a method for the preparation of zirconium-89 radiolabelled chitosan nanoparticles as an application for leukocyte trafficking with positron emission tomography

Positron Emission Tomography is an attractive imaging modality for monitoring the migration of cells to pathological tissue. We evaluated a new method for radiolabelling leukocytes with zirconium-89 (89Zr) using chitosan nanoparticles (CN, Z-average size 343 ± 210 nm and zeta potential +46 ± 4 mV) as the carrier. We propose that cell uptake of 89Zr-loaded CN occurred in a two-step process; cell membrane interaction with 89Zr-loaded CN was followed by a slower cell internalisation step.