Triplet-Triplet Annihilation Upconversion-Based Photolysis: Applications in Photopharmacology

The emerging field of photopharmacology is a promising chemobiological methodology for optical control of drug activities that could ultimately solve the off-target toxicity outside the disease location of many drugs for the treatment of a given pathology. The use of photolytic reactions looks very attractive for a light-activated drug release but requires to develop photolytic reactions sensitive to red or near-infrared light excitation for better tissue penetration. This review will present the concepts of triplet-triplet annihilation upconversion-based photolysis and their recent in vivo applications for light-induced drug delivery using photoactivatable nanoparticles. Photopharmacology is a promising chemobiological methodology for optical control of drug activities. This review is focused on the recent development of triplet-triplet annihilation upconversion-based nanoparticles and their combination with photoremovable protecting groups in order to release drugs with excitations in the photo-therapeutical window, with particular attention on the in vivo applications of such smart drug delivery systems. image