64Cu loaded liposomes as positron emission tomography imaging agents

Area of Science:

• Nanomedicine
• Radiopharmaceutical Chemistry
• Medical Imaging

Background:

• Liposomes are versatile nanocarriers with potential in medical imaging.
• Efficiently incorporating radionuclides into liposomes for imaging remains a challenge.
• Positron Emission Tomography (PET) requires stable and quantifiable imaging agents.

Purpose of the Study:

• To develop a highly efficient method for loading copper-64 into liposomes for PET imaging.
• To evaluate the utility of these radiolabeled liposomes for in vivo quantitative imaging.
• To demonstrate the application of this method for characterizing liposome-based nanomedicine.

Main Methods:

• Developed a remote loading technique using the ionophore 2-hydroxyquinoline to transport copper-64 across liposome membranes.
• Encapsulated a copper-chelator within preformed liposomes.
• Utilized positron emission tomography (PET) for in vivo imaging studies in mice.

Main Results:

• Achieved highly efficient copper-64 loading (95.5 ± 1.6%) into liposomes.
• Demonstrated excellent retention stability of the radionuclide (>99%).
• Successfully performed quantitative in vivo PET imaging in healthy and tumor-bearing mice.

Conclusions:

• The developed remote loading method provides highly efficient and stable copper-64 labeled liposomes for PET imaging.
• This technique is a powerful tool for characterizing liposome in vivo performance.
• The (64)Cu-liposomes show significant potential for diagnostic and therapeutic nanomedicine applications.