An improved method for in vivo tracing and imaging of liposomes using a gallium 67-deferoxamine complex

We have developed a new method for tracing and imaging liposomes in vivo based on the encapsulation of a gallium 67-deferoxamine ⁶⁷Ga-DF) complex in the liposomal water phase. This method combines several advantages over other published methods: extremely high affinity of ⁶⁷Ga for DF, thus avoiding the problem of metal translocation to various plasma proteins; rapid renal clearance rate of⁶⁷Ga-DF complex, thus minimizing the background of radioactivity in non-liposome-associated form; and use of⁶⁷Ga, a readily available, short half-life gamma-emitter convenient for dosimetry and imaging, which can be efficiently loaded into preformed liposomes.