Imaging of Gadolinium Spatial Distribution in Tumor Tissue by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

Purpose
Laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) was utilized in postmortem imaging of gadolinium (Gd) spatial distribution in a mouse tumor model postadministration of PEGylated Gd liposomal nanoparticles.
Procedures
PEGylated liposomal nanoparticles were formulated using a paramagnetic lipid incorporating Gd, in addition to a fluorescent lipid, and injected intravenously into Balb/C nude mice bearing IGROV-1 tumors. At postinjection (2 h), the tumors and selective organs were imaged by magnetic resonance imaging (MRI) and, after excision, by histology and LA–ICP–MS.
Results
The presence of Gd within tumor tissue was confirmed by LA–ICP–MS and when correlated to histology was found to be prevalent in regions of higher vascularity. The presence of Gd in the kidneys was also confirmed.
Conclusions
We have demonstrated, in a novel manner, the use of LA–ICP–MS for the spatial detection of Gd in tumor tissue. LA–ICP–MS is valuable in providing spatio-specific information of MRI contrast agents and more importantly Gd in tumor tissue.