Comparison of three remote radiolabelling methods for long-circulating liposomes

摘要

Long-circulating liposomes (LCL) are often used as a drug carrier system to improve the therapeutic index of water-soluble drugs. To track these LCL in vivo, they can be radiolabelled with In-111-oxine. For this labelling-method, generally DTPA is encapsulated in the aqueous phase of LCL (DTPA-LCL). Alternatively, LCL can be labelled with (InCl3)-In-111 after incorporation of DTPA-conjugated DSPE in the lipid bilayer (DTPA-DSPE LCL). Here, we compared the in vitro properties of DTPA-DSPE LCL with those of DTPA LCL and empty LCL. Additionally, we compared the in vivo performance of DTPA-DSPE LCL with those of DTPA LCL in mice.