ABSTRACT
Controlling the rate of drug release from liposomal carriers is essential for optimum drug delivery (1,2). Liposome formulations that are too unstable release their drug while still in the general circulation, thus reducing the benefits of site-specific drug delivery resulting from the enhanced permeability
and retention effect and allowing for many of the systemic toxicities associated with the unencapsulated agent. Formulations that are too stable risk not making the drugs bioavailable, and thus able to act on their molecular targets. Furthermore, delivery strategies that rely on molecular targeting of solid tumors, including immunoliposomes, require that the liposomal drug formulation arrive at the cancer cell intact to take full advantage of the benefits of targeting (3,4).
