| 摘要 |
A method for introducing a drug, imaging agent and/or other chemical agent into the systemic circulation comprises providing a the drug, imaging agent and/or other chemical agent in liposomes having a mean diameter of less than about 200 nm, preferably less than about 80 nm, as determined by negative-staining transmission electron microscopy. The liposomes are orally administered. It has been found that liposomes of such small sizes are not absorbed by the macrophages in the Peyer's patches of the gut, but instead are introduced into the venous circulation from the Peyer's patches, and then through the portal vein or inferior vena cava system, through the heart, and into the systemic circulation. |
