ABSTRACT
The discovery of drug delivery systems that could carry a biologically active molecule to a targeted tissue and release its payload at the right time and position to mediate an effective therapeutic response has been the subject of intensive research activity. Among available drug delivery tools, liposomes offer many advantages (1). Strategies developed to improve liposomemediated drug delivery include the enhancement of biodistribution (e.g., stability in the bloodstream, targeting specific tissues or cells) and facilitation of site-specific delivery (2). Indeed, an ideal carrier should transport its cargo to a specific tissue and then deliver it efficiently. Even though the development of sterically stabilized liposomes (namely ‘‘stealth liposomes’’) (3) and the use of targeting ligands have considerably improved systemic transport efficacy (4), a therapeutically relevant targeted liposomemediated drug delivery system has not yet been developed. One expected property would be a site-specific destabilization of the liposome, inducing the release of the biologically active molecule where and when necessary to get an optimal biological response.
