Phototriggered targeting of nanocarriers for drug delivery

Stimuli-triggered targeting of drug delivery systems can both increase the therapeutic efficacy and lower toxicity by selectively delivering drugs at target sites with high specificity and efficiency. Light is a convenient and powerful stimulus for use in such drug delivery systems because it is readily available and noninvasive and offers excellent spatiotemporal control. The power and wavelength of light can be finely tuned for different photoresponsive systems to achieve efficient targeting at the tissue, cellular, or subcellular levels. Here, we have reviewed the various mechanisms for phototriggered targeting (phototargeting) of drug nanocarriers. We have discussed the three main phototargeting strategies: (1) targeting ligand activation; (2) particle size reduction; and (3) blood vessel disruption.