A medical device and method for transportation and release of a therapeutic agent
into a mammalian body are disclosed. The medical device is coated with alternating
layers of a negatively charged therapeutic agent and a cationic polyelectrolyte,
following a controlled adsorption technique. The method is simple, with minimal
perturbation to the therapeutic agent and uses clinically acceptable biopolymers
such as human serum albumin. The amount of the therapeutic agent that can be delivered
by this technique is optimized by the number of the layers of the therapeutic agent
adsorbed on the surface of medical device. There is a washing step between alternate
layers of the therapeutic agent and cationic polyelectrolyte carrier, so that the
amount of the therapeutic agent on the insertable medical device represents the
portion that is stably entrapped and adsorbed on to the medical device. The insertable
medical device and method according to this invention are capable of reproducibly
delivering therapeutic agent to a site in a mammalian body, and allow for a highly
reproducible and controllable release kinetics of the therapeutic agent.
