Light-responsive emulsions and dispersions: Design and applications

The response of molecules to light can have a dramatic impact on the stability, morphology, and controlled release from emulsions or dispersions. In this review, we discuss the underlying mechanisms enabling light-responsive behaviour - including photoswitching, photodestruction, and photothermal effects – in surfactant- and particle-stabilised emulsions, and dispersions of structured lipid nanoparticles. We critically evaluate the recent literature to demonstrate the precise control that can be achieved over a wide range of parameters, including droplet size, stability, and release. Finally, we summarise the emerging applications of these systems, identify current challenges, and suggest future research directions.