Light Responsive Materials: Properties, Design, and Applications
Priya Ranjan Sahoo
Abstract
Light is one of the safe external stimuli that can be externally applied to alter chemical/biochemical behavior offering significant potential in photopharmacology. Since it is easy to use light, achieving precise drug delivery is possible. Light could be used to switch bacterial activity in cells including inhibition and release. Interestingly, the biochemical functions can be controlled both spatially as well as temporally using externally administered light. Light can also be used to regenerate the materials a number of times depending on the reversible nature of the material. This chapter is focused on light responsive materials including azobenzenes and spiropyrans. Materials can be tailored by modifying the basic delivery system with light responsive chemical structures such as spiropyrans and azobenzene moieties in their architecture. Such type of responsive materials could be augmented for use in medical devices, drug transport and delivery etc. Several new technologies involving light activated drug carriers such as nanoimpellers, nanovalves based drug delivery are elucidated with recent examples. Materials or surface modified with light responsive tools can offer controlled response due to existence of two different forms (such as spiropyran-merocyanine or cis-trans) which can facilitate either retention or release of the drugs.