1985 Volume 8 Issue 3 Pages 206-210
Disappearance from the blood and lymphatic delivery of human fibroblast interferon (HuIFN-β) in rats by the various administration routes were studied. Intravenous injection showed a rapid disappearance of HuIFN-β from the blood circulation, however, the clearance rate was greatly decreased after 2 h and the half-lives were 15 min and 2.0 h. Intramuscular, subcutaneous and intraperitoneal injections maintained readily detectable levels in the blood for 12 h, and the half-lives were 2.3, 1.7 and 1.2 h, respectively. Lipid-surfactant mixed micelles greatly promoted the absorption of HuIFN-β from the large intestine with extremely high selective lymphatic delivery, whereas intravenous and intramuscular injections showed no selective transfer into the lymphatics.