Targeted Drug Delivery: A Two-Compartment Growth Inhibition Assay Demonstrates That Fluorodeoxyuridine and Fluorodeoxyuridine Monophosphate Are Liposome-Independent Drugs

Publisher Website
Google Scholar
Abstract
The targeted delivery to cells by liposomes and leakage under delivery conditions of fluorodeoxyuridine (FdUR) and fluorodeoxyuridine monophosphate (FdUMP) have been evaluated using a two-compartment growth inhibition assay. Under cell culture conditions, FdUR leaks 100% from all liposomes regardless of charge or phase transition temperature. Under the same conditions, FdUMP leaks 100% from egg yolk phosphatidylglycerol liposomes, 47% from distearoylphosphatidylglycerol liposomes, 44% from egg yolk phosphatidylcholine liposomes, and 10% from distearoylphosphatidylcholine liposomes. All liposomes were prepared from a 67:33 mixture of phospholipid and cholesterol. The two-compartment assay demonstrated directly that neither of these drugs is delivered selectively to the target cells by the liposomes, suggesting that they are liposome independent drugs.