photosensizers

Photosensitizers are molecules that, upon absorbing light energy, become chemically reactive. This reactivity is typically an excited triplet state, which can then interact with other molecules through processes like energy transfer or electron transfer. These interactions lead to the generation of reactive oxygen species (ROS), such as singlet oxygen or superoxide radicals, or can directly participate in photochemical reactions. The specific properties of a photosensitizer, including its absorption spectrum and photochemical pathways, depend on its molecular structure. Photosensitizers find applications in various fields. In medicine, they are used in photodynamic therapy (PDT) to treat cancers and other diseases. In this context, a photosensitizer is administered to a patient, accumulates in the target tissue, and is then activated by light of a specific wavelength, generating ROS that kill the diseased cells. Photosensitizers are also employed in photocatalysis, where they initiate chemical reactions using light energy, and in materials science for processes like photopolymerization. The efficiency and selectivity of photosensitizers are crucial for their effectiveness in these diverse applications.