Sep 24, 2008
Nanoparticles stick around for longer
Philips Research of the Netherlands is teaming up with the University of Urbino in Italy to develop contrast agents for medical imaging applications. The research alliance will study the encapsulation of magnetic-nanoparticle-based agents inside living blood cells, with a view to prolonging their retention time in blood.
Nanoparticle-based contrast agents show considerable promise for use in diagnostic imaging. However, when injected as free particles, they are quickly excreted from the blood via the patient's liver, limiting their usefulness. By capturing the magnetic nanoparticles inside the patient's own red blood cells, they remain protected from the body's excretion mechanisms for much longer periods - possibly as long as 120 days, the typical lifetime of a healthy red blood cell.
The collaboration will last for approximately two and a half years, during which time the Urbino researchers will investigate the integration of the magnetic nanoparticles into red blood cells and examine their biological interactions in the body. The technology could allow the preparation of relatively large volumes of contrast-agent-loaded blood, enabling Philips to evaluate the effectiveness of the contrast agents in its medical scanners, with the aim of optimizing the scanning parameters.
"Together with the unique expertise of the researchers at the University of Urbino, we hope to increase the retention time of these particles from minutes to hours or even days," said Henk van Houten, senior vice-president of Philips Research and head of the Healthcare Research program. "This would open up applications such as the image-based monitoring of complex cardiovascular interventions that can take hours to complete."
For example, the encapsulated nanoparticles could be used to highlight the volume of blood in different heart chambers during radio-frequency ablation. This minimally invasive procedure, used to treat heart rhythm disorders, involves inserting a catheter into the patient's heart and can last several hours. The encapsulated nanoparticles should remain in the body for the full duration of such a procedure.
"Our close collaboration with Philips should speed the translation of our invention into clinical practice," said Mauro Magnani, vice-rector of the University of Urbino. "With our technology, the use of new biomimetic constructs that merge the properties of nanomaterials with those of living cells is finally possible, bringing the real advantages of nanomaterials for therapeutic and diagnostic applications to patients."