lysaktive

Lysaktive is a Danish term used to describe substances or processes that become active when exposed to light. In English-language contexts, the concept is usually described as light-activated or photoactive. Lysaktive materials and systems respond to photons by undergoing chemical, electronic, or conformational changes that enable activity otherwise unavailable in the dark.

Photons promote molecules to excited states, leading to reactions such as bond cleavage, electron transfer, or changes in shape. This enables controlled activation, deactivation, or release of cargo. Common examples include photosensitizers for photodynamic therapy; photoactivatable prodrugs that release an active drug upon illumination; optogenetic tools such as channelrhodopsins that regulate cellular activity with light; and light-responsive polymers or surfaces that alter their properties on demand.

Applications span medicine, materials science, and agriculture, offering spatial and temporal control over activity. Challenges include limited light penetration in tissue, potential phototoxicity, the need for specific wavelengths and light sources, and chemical stability. Regulatory and safety considerations are important for medical uses.

See also: photopharmacology; photosensitizer; optogenetics; photoresponsive material.