Drug Delivery Systems

In the development of drug delivery systems, the principles of photochemistry have been exploited for the encapsulation of drugs in matrices as well as their photocontrolled release. For the former purpose, non-biodegradable and biodegradable synthetic matrices have been developed, and natural polymers, including proteins and polysaccharides, have been utilized after derivatization. For the latter use, non-photodegradable and photodegradable systems have been also fabricated. Non-photodegradable systems are based on the response to ultraviolet/visible light and photothermal stimulations. Photodegradable polymers are designed by inserting photodegradable groups in the main chain, crosslinker, or side chains. Near infrared-sensitive polymers have also been utilized for this application. This chapter introduces multiple-triggered release systems with a comprehensive review of these issues.