Non-PEGylated DOTA Liposomes for Remote Loading Radioactive Divalent Cations

DOTA encapsulated liposomes are used for remote loading of radioactive divalent ions such as radioactive copper into the liposomes. Cationic ions will not pass through the membrane if there is no pH gradient. Divalent ion will cross the liposome membrane only when there is a flux of proton across of the lipid membrane. Due to the difference in the pH inside and outside of the liposomes, there will be a constant flux of proton from inside of the liposomes to outside of the liposomes. Due to this flux, divalent cations move in the opposite direction from outside to inside of liposomes. Liposomes are thermodynamically stable structures and not very permeable to divalent cations after they are formed. If there is no pH gradient, the divalent cations cannot move from outside to inside of the liposomes, where they will remain outside and won’t cross the membrane. The driving force for remote loading in proton gradient.
The radioactive divalent copper is externally added to the liposomes. The divalent ion passes the membrane using pH gradient method and chelates DOTA.

MSDS of Non-PEGylated DOTA Liposomes for Remote Loading Radioactive Divalent Cations