cRGD-conjugated magnetic-fluorescent liposomes for targeted dual-modality imaging of bone metastasis from prostate cancer

Abstract

We reported the development of multifunctional liposomes as a dual-modality probe to facilitate targeted magnetic resonance and fluorescent imaging of bone metastasis from advanced cancer. Multifunctional liposomes consisted of liposomes as a carrier, hydrophobic CdSe QDs in phospholipid bilayer, hydrophilic iron oxide nanoparticles in interior vesicle, lipid-PEG derivative on the surface and cRGDyk peptide conjugated to distal ends of lipid-PEG derivative. Excellent stability, effective detection signal, low toxicity, high resistance to phagocytosis by macrophages and good specificity to tumor of multifunctional liposomes were confirmed by in vitro characterization. The in vivo results demonstrated that multifunctional liposomes accumulated mainly in tumor and liver, indicating that targeted dual-modality imaging was achieved, and the results from two kinds of modalities were consistent and complementary. These findings provide a helpful strategy for detection of bone metastases in a more effective manner for initiation of appropriate therapy.

• Bone metastasis
• dual-modality imaging
• iron oxide nanoparticles
• liposome
• quantum dots
• RGD peptide

Declaration of interest

The authors have no conflict of interest to declare. The work was supported by the National Natural Science Foundation of China (31171143), the National Important Science Research Program of China (2011CB933503), the National Key Technology Research and Development Program of China (2012BAI23B02), the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (12KJD310004) and the Applied Basic Research Project Foundation of Nantong (BK2012064).